Inorganic Porous Materials

Oil spills are an urgent global problem that has been worsening over the last 4 years (ITOPF., 2023). Devastating nearby ecosystems and disrupting economies, they can contaminate water and cause longlasting damage. For example, the multibillion-dollar fishing industry is affected severely by oil spills. Despite the development of efficient sorbents, the method of sorbent deployment ultimately decides the effectiveness of cleanup efforts. OCTOPAS (Oil Spill Cleanup through an Optimized Pragmatic Automated System), is a novel sorbent deployment method which cleans up oil spills much more efficiently than conventional methods. OCTOPAS has 2 main components, a digital app and a physical boat. Using a novel algorithm, OCTOPAS App generates the optimal path to deploy the sorbents. OCTOPAS Boat gets this instruction and deploys sorbents pragmatically. Using OCTOPAS to deploy sorbents is on average 217.9% more efficient than the conventional method. In the real world, OCTOPAS can be stowed on oil tankers, ready to be used immediately. This immediate deployment can limit the spread and improve the efficiency of oil spill cleanups by a significant margin.

The structural changes of synthetic beidellite and Al -pillared analogues during dehydroxyla-13 Ž . tion were studied using infrared emission spectroscopy IES . The OH-stretching region is characterised by 2 OH-stretching modes around 3605 cm y1 and 3650 cm y1 . These bands strongly decrease in intensity upon dehydroxylation of the beidellite up to 700-7508C. The Al -pillared

The structural changes of synthetic beidellite and Al -pillared analogues during dehydroxyla-13 Ž . tion were studied using infrared emission spectroscopy IES . The OH-stretching region is characterised by 2 OH-stretching modes around 3605 cm y1 and 3650 cm y1 . These bands strongly decrease in intensity upon dehydroxylation of the beidellite up to 700-7508C. The Al -pillared

Nuclear Magnetic Resonance (NMR) cryoporometry is a technique for non-destructively determining pore size distributions in porous media through the observation of the depressed melting point of a confined liquid. It is suitable for measuring pore diameters in the range 2 nm -1 µm, depending on the absorbate. Whilst NMR cryoporometry is a pertabative measurement, the results are independent of spin interactions at the pore surface and so can offer direct measurements of pore volume as a function of pore diameter. Pore size distributions obtained with NMR cryoporometry have been shown to compare favourably with those from other methods such as gas adsorption, DSC thermoporosimetry, and SANS. The applications of NMR cryoporometry include studies of silica gels, bones, cements, rocks and many other porous materials. It is also possible to adapt the basic experiment to provide structural resolution in spatially dependent pore size distributions, or behavioural information about the confined liquid.

Ten montmorillonite type clay samples from Miles, Queensland, Australia, have been characterised using XRD, ICP-AES and infrared spectroscopy. The Na-exchanged sample DH-30 was used for pillaring with Al 13 by exchange with an Al(NO 3 ) 3 /NaOH solution with an approximate OH/Al molar ratio of 2.2. The XRD pattern for the expanded smectite provided evidence that the Na/Al 13 polymer exchange had occurred. XRD patterns for the raw sample, the Na-exchanged clay and the Al 13 exchanged clay resulted in d-spacings of 15.09, 15.73 and 17.42 Å, respectively. Calcination at 600°C of the Al 13 -smectite led to a minor decrease in basal spacing to approximately 16.5 Å. The effect of temperature on the Al 13 -expanded smectite was also apparent when the d-spacing of an air-dried sample (19.44 Å) was compared to that of an oven-dried (60 o C) sample (17.42 Å). This difference was due to the loss of water molecules from the Al 13 outer sphere of hydration.

A natural and biodegradable material that has good oil absorbtivity, high durability and reusability is one of the most demanded materials in the industry nowadays. It is believed to have potential to replace polypropylene function as the commercialized sorbent. One of material that suits this function is kapok fibre or commonly known as cotton. Using kapok, decomposition process, which always become an issue when dealing with polypropylene, is no more a problem. The nature of Kapok will allow it to decompose naturally without any harm threat to the environment. Besides, kapok has fibrous microstructure that becomes the key factor to absorb oil efficiently. Without any chemical modification, it can absorb significant amount of oil like polypropylene. This project was conducted to evaluate kapok capacity as the natural sorbent in terms of application. A series of test was done to analyze the surface microstructure, sorption capacity, dynamic oil retention and its reusability. Two experimental setups are prepared for sorption and desorption analysis. Findings of this paper are found base on the weight of oil recovered and HPLC test for seawater composition. It is believed that this project can prove the potential of Kapok as sorbent for oil spill cleanup at the end of this paper.

Amorphous manganese oxide and binary copper manganese oxides were synthesized using the redox method, characterized, and tested in the catalytic oxidation of ethylene. The catalytic activity of the synthesized catalysts toward ethylene oxidation was high (100% conversion of 1.0% C 2 H 4 at 200 • C with space velocity of 35, 000 mL h −1 g −1 cat) and compared favorably with that of a commercial Hopcalite catalyst. The high catalytic activity was attributed a combination of factors including the poor crystallinity, the high surface areas (≥163 m 2 g −1), porosity, presence of Mn 4+ species, and compositional homogeneity of the synthesized copper manganese oxides. Incorporation of copper into the amorphous manganese oxide matrix significantly enhanced the catalytic activity of the resultant bimetallic oxides by increasing the reducibility and ease of removal of lattice oxygen species. The synthesized materials were characterized using FE-SEM, HR-TEM, BET, FAAS, XPS, and TPD methods.

Starting from TMOS and implementing co-gelation in the sol-gel method, silica was hybridized with an industrial formulation of bovine casein. The hybrid alcogels were dried in supercritical CO 2 to yield crack-free silica-casein aerogel monoliths of casein contents ranging from 4.7 wt% to 28 wt%. Cross-linked hybrid aerogels were produced from formaldehyde treated alcogels. The microstructures and the morphologies of the silica-casein aerogels highly resemble to that of pristine silica aerogels. The primary building blocks are spherical particles that interconnect into mesoporous networks (average d pore = 20 nm and S BET = 700 nm 2 /g), as shown by SEM, small-angle neutron scattering (SANS) and N 2 adsorption-desorption porosimetry. Contrast variation SANS experiments show that silica and casein form homogeneous nanocomposite backbones. The interaction of water with silica-casein aerogels was investigated by SANS, and by NMR cryoporometry, relaxometry and diffusiometry. Even when fully saturated with water, the hybrid silica-casein aerogels retain their original, highly permeable, open mesoporous structures that formed under supercritical drying. This represents a unique and advantageous wetting mechanism among hybrid inorganic-biopolymer materials, since the strong hydration of the biopolymer component often causes the deformation of the backbone and the consequent collapse of the porous structure. Silica-casein aerogels are biocompatible and inert for CHO-K1 cells.

The size and distribution of pores have been studied through the melting behavior of water confined in white cement samples by ~H nuclear magnetic resonance cryoporometry. It is found that the sample cured at 298 K shows a considerably coarser pore structure in the range of pores from 1 to 15 nm when compared with the samples cured at 278 K. With the addition of the Sika Rapid 2 antifreeze admixture in the cement cured at 278 K, an increase of pores between 5 and 15 nm anda more homogeneous distribution of small pores from 1 to 5 nm is observed when compared with cement cured at the same temperature but without the antifreeze additive. The positive influence of Sika Rapid 2 antifreeze admixture on the mechanical properties of cement cured at a lower temperature was also found through the compressive strength measurements performed for the studied cement samples asa function of the cu¡ age.

Multiple research areas have emerged in view of the deleterious impacts of oil-spills on the environment and the relative intractability of the problem per se. The dimensions mostly explored thus far, relate to the prediction of the fate of oil-spill and development of effective countermeasures. Among the counter measures, development of effective sorbents for oil-spill remediation has sustained interest for quite long, in spite of the numerous challenges associated with it. Most importantly, the sorbent materials need to be assembled in such a structure or form that they can survive the oceanic currents and other prevailing environmental conditions without themselves becoming a source of secondary pollution. This review paper focuses on the chronological development of such assemblies or devices over the past century and a critical appraisal of the same. Relevant major factors affecting the performance of sorbent assemblies can be identified as: structural features and modes of sorption, effect of weathering on oil-sorption capacity, mode of distribution and harvesting of such absorbent units, and the final disposal after feasible cycles of sorption and release. This review paper incorporates a detailed discussion on the major inventions and the extant open literature in this field.

A comparative absorption capability analysis was conducted using adapted polyurethane foam as crude oil Sorbents. The used Crude oil has been brought from the west of the Qurna city oil field with A.P.I. equals 22.2-27. API measures how heavy or light a petroleum liquid is compared to water; crude oil's sorption and absorption ratio amounts are investigated. The findings demonstrate that the absorption ratio of fluff feather to wing feather is very distinct. The fluff feather absorbed much more crude oil than the wings. Moreover, much crude oil absorption causes the three types of feathers to plunge into crude oil. Owing to the disparity of the capillary structures of pure and modified polyurethane and the particular arrangement of the feathers, the absorption of modified polyurethane foam is beyond pure foam. The absorption ratio is saturated at (240-270) % (where the modified foam releases some additional volume of crude oil rather than the saturation ratio). Because of the cross-link density inside the modified foam, the last results were clarified. Also, we analyzed the effect of 10 holes on the absorption ratio in which the absorption is less than the unpinned ratio.

Amorphous manganese oxide and binary copper manganese oxides were synthesized using the redox method, characterized, and tested in the catalytic oxidation of ethylene. The catalytic activity of the synthesized catalysts toward ethylene oxidation was high (100% conversion of 1.0% C 2 H 4 at 200 • C with space velocity of 35, 000 mL h −1 g −1 cat) and compared favorably with that of a commercial Hopcalite catalyst. The high catalytic activity was attributed a combination of factors including the poor crystallinity, the high surface areas (≥163 m 2 g −1), porosity, presence of Mn 4+ species, and compositional homogeneity of the synthesized copper manganese oxides. Incorporation of copper into the amorphous manganese oxide matrix significantly enhanced the catalytic activity of the resultant bimetallic oxides by increasing the reducibility and ease of removal of lattice oxygen species. The synthesized materials were characterized using FE-SEM, HR-TEM, BET, FAAS, XPS, and TPD methods.

Offshore oil spills are unfortunately common during extraction and transport processes. When it happens, the first action is contingency, followed by oil removal. Skimmers, incineration, and sorption in porous structures are some of the techniques commonly used. Polyurethane foams (PU), for example, are highly porous polymers. Due to a lack of legislation and environmental education, post-consumer PU foams are found irregularly discarded throughout Brazilian cities. This work aims to promote the reuse of this residue to sorb offshore oil spills. Postconsumer PU foams were cleaned and surface modified through sonication technique for impregnation with MoS 2. Scanning Electron Microscopy (SEM) + Energy-Dispersive X-ray Spectroscopy (EDS) and contact angle were the characterizations performed. SEM images showed that the unchanged post-consumer PU foam (Un-PC) surface went from smooth to rough after MoS 2 impregnation (MoS 2-PC). C, N, and O together represented 99.05 %atoms of Un-PC composition. For MoS 2-PC, C, N, plus O represented 66.13 %atoms, while S and Mo represented 26.92 %atoms and 6.95 %atoms, respectively. The contact angle increased from 104.4° (Un-PC) to 123.3° (MoS 2-PC). This increase was due to hydrophobization caused by MoS 2 particles. Three sorption tests were performed. In the first one, when only seawater was used, MoS 2-PC (7.42 ± 0.22 g‧g-1) sorbed statistically less seawater than Un-PC (9.98 ± 0.22 g‧g-1). In the second system, only with lubricating oil S46 (~46 cSt), MoS 2-PC increased about 16.5x the sorption capacity compared to Un-PC, reaching up to 24.13 ± 0.00 g‧g-1. The third sorption test was performed in a multi-component system formed by seawater (92%):(8%) lubricating oil S46. While Un-PC was able to absorb 0.08 ± 0.00 g‧g-1 of seawater and 3.20 ± 0.28 g‧g-1 of lubricating oil S46, MoS 2-PC absorbed 0.75 ± 0.06 g‧g-1 and 32.81 ± 0.02 g‧g-1 of seawater and lubricating oil S46, respectively. Although there was an increase in seawater sorption between Un-PC and MoS 2-PC, the increase in oil sorption was much more significant (925% or 10.25x). The roughness caused by the MoS 2 particles on the polyurethane surface combined with the increase in intermolecular forces of Van der Waals type proved its strong influence in increasing the sorption capacity and its selectivity for oil over water. Here one waste was successfully used to remove another, which showed that post-consumer foams are a viable and highly cost-effective option for oil spill recovery.

Red mud is a highly alkaline and hazardous waste generated during alumina production, but its recycling and reuse, despite decades of intensive research, still remains a huge challenge for alumina refining industries. The global red mud stockpile is estimated to reach four thousand million tonnes [1]. This distressing scenario is attributed to the wastes' strong alkalinity, particle fineness, and toxicity, which hinders recycling. In fact, less than 2.7% of the annual red mud production (150 million tonnes) is reused [2], while most of it is disposed of in large lagoons or tailing dams. This means that the already significant red mud stockpile will inevitably increase by 144 million tonnes per year, unless innovative and high-volume applications are implemented. Catastrophic disasters in Hungary (2010) and China (2016), whose long-term impacts on the environment and human health are still being evaluated, have raised public awareness over current red mud management methodologies. This greater public perception may be the driving force to change the alumina industry paradigm to consider red mud as a resource not as a waste. In this context, novel, low cost, and environmentally benign strategies to prevent/mitigate red mud disposal are imperative. One interesting approach to reuse red mud could

Background: With every oil tanker comes the risk of an accident and oil spill. Sorbents are the most suitable means to remove oil spills. Aerogels as sorbents have high porosity and can be made from cellulose from paper waste. The literature does not distinguish between paper and cardboard as sources of cellulose aerogels and little is known about composites of cellulose aerogels consisting of cellulose fibres and chemically untreated, unprocessed fibres or particles of straw, wool, macroalgae or cellulose acetate from cigarette butts. In this study, the sorption properties for marine diesel oil and biodiesel of such aerogels and their regenerative capacity with bioethanol were investigated. Methods: Cellulose aerogels were prepared from office paper and cardboard waste without and with chemically untreated algae, straw, wool and cellulose acetate as a composite by freeze drying. All samples were hydrophobised with methylsilane. The density to calculate the porosity and the contact angle were determined. Then the sorption capacity was determined over five cycles of sorption of oil and regeneration with bioethanol. Results: The average contact angle of all samples was 125 , indicating hydrophobicity. Paper-based aerogels were found to consistently have higher sorption capacities for biodiesel, marine diesel oil and bioethanol than cardboard-based aerogels. In particular, the wool/cellulose aerogel composite was found to have better sorption capacity for biodiesel, marine diesel oil and bioethanol than all other samples. The cellulose acetate/cellulose aerogel composite showed significantly higher sorption capacities than the paper and cardboard control samples (highest value is 32.25 g g −1) only when first used as a sorbent for biodiesel, but with a rapid decrease in the following cycles.

A comparative absorption capability analysis was conducted using adapted polyurethane foam as crude oil Sorbents. The used Crude oil has been brought from the west of the Qurna city oil field with A.P.I. equals 22.2-27. API measures how heavy or light a petroleum liquid is compared to water; crude oil's sorption and absorption ratio amounts are investigated. The findings demonstrate that the absorption ratio of fluff feather to wing feather is very distinct. The fluff feather absorbed much more crude oil than the wings. Moreover, much crude oil absorption causes the three types of feathers to plunge into crude oil. Owing to the disparity of the capillary structures of pure and modified polyurethane and the particular arrangement of the feathers, the absorption of modified polyurethane foam is beyond pure foam. The absorption ratio is saturated at (240-270) % (where the modified foam releases some additional volume of crude oil rather than the saturation ratio). Because of the cross-link density inside the modified foam, the last results were clarified. Also, we analyzed the effect of 10 holes on the absorption ratio in which the absorption is less than the unpinned ratio.

Starting from TMOS and implementing co-gelation in the sol-gel method, silica was hybridized with an industrial formulation of bovine casein. The hybrid alcogels were dried in supercritical CO 2 to yield crack-free silica-casein aerogel monoliths of casein contents ranging from 4.7 wt% to 28 wt%. Cross-linked hybrid aerogels were produced from formaldehyde treated alcogels. The microstructures and the morphologies of the silica-casein aerogels highly resemble to that of pristine silica aerogels. The primary building blocks are spherical particles that interconnect into mesoporous networks (average d pore = 20 nm and S BET = 700 nm 2 /g), as shown by SEM, small-angle neutron scattering (SANS) and N 2 adsorption-desorption porosimetry. Contrast variation SANS experiments show that silica and casein form homogeneous nanocomposite backbones. The interaction of water with silica-casein aerogels was investigated by SANS, and by NMR cryoporometry, relaxometry and diffusiometry. Even when fully saturated with water, the hybrid silica-casein aerogels retain their original, highly permeable, open mesoporous structures that formed under supercritical drying. This represents a unique and advantageous wetting mechanism among hybrid inorganic-biopolymer materials, since the strong hydration of the biopolymer component often causes the deformation of the backbone and the consequent collapse of the porous structure. Silica-casein aerogels are biocompatible and inert for CHO-K1 cells.

Fast field-recycling magnetic resonance relaxometry (FFC NMR) was applied to measure the spin-lattice relaxation time, T 1 , of protons in pure ionic liquid (IL) 1-butyl-3-methylimidazolium chloride (BMIMCl) and when confined in cellulose (Cell) ion gel (Cell/BMIMCl) at different temperatures and different Larmor frequencies. The rotational and translational contributions were taken to interpret the relaxation data of neat BMIMCl and were described by Woessner's and Torrey's theoretical models, respectively. The ionic liquid-cellulose matrix interaction detected in 10 wt% polymer-ion gel was interpreted on the basis of a dynamical process called reorientation mediated by translational displacements (RMTD), which allow explanation of the significant slowing of the dynamics of IL cations at cellulose surfaces. Two types of cation diffusion were identified in this gel: a long-range translational diffusion within large cavities of the Cell matrix and diffusion occurring at the polymer surface. The correlational time constants and self-diffusion coefficients of the BMIMCl ionic liquid in bulk-like state and interaction with the cellulose matrix surface were determined. The conductivity measurements performed for pure IL and that confined in the Cell/BMIMCl ion gel show that the gelation only results in a small decrease of the ionic conductivity.

Red mud is a highly alkaline and hazardous waste generated during alumina production, but its recycling and reuse, despite decades of intensive research, still remains a huge challenge for alumina refining industries. The global red mud stockpile is estimated to reach four thousand million tonnes [1]. This distressing scenario is attributed to the wastes' strong alkalinity, particle fineness, and toxicity, which hinders recycling. In fact, less than 2.7% of the annual red mud production (150 million tonnes) is reused [2], while most of it is disposed of in large lagoons or tailing dams. This means that the already significant red mud stockpile will inevitably increase by 144 million tonnes per year, unless innovative and high-volume applications are implemented. Catastrophic disasters in Hungary (2010) and China (2016), whose long-term impacts on the environment and human health are still being evaluated, have raised public awareness over current red mud management methodologies. This greater public perception may be the driving force to change the alumina industry paradigm to consider red mud as a resource not as a waste. In this context, novel, low cost, and environmentally benign strategies to prevent/mitigate red mud disposal are imperative. One interesting approach to reuse red mud could

Recently developed montmorillonite clay-based aerogels have attracted an attention owing to their highly porous internal structure. This study deals with the design of experiments applied for preparation of clay aerogel polymer composites and their testing and optimization for oil spill sorption. Three design variables have been chosen for experimentation, i.e. the amounts of montmorillonite (MMT), polyvinyl alcohol (PVA) and sodium dodecyl sulfate (SDS). Based on the experimental design the response surface models have been constructed. The objective for optimization was to maximize the performances of materials for sorption of dodecane and motor oil. To this end, the multi-objective optimization problem has been solved using NSGA-II optimization algorithm. The aerogel sorbent prepared under the optimal conditions of 2.109% w/v PVA, 2.678% w/v MMT and 0.210% w/v SDS bestowed the best sorption performance for both dodecane (23.63 g/g) and motor oil (25.84 g/g). Finally, the hydrophobic aerogel sorbent has been prepared using trimethoxy(octadecyl)-silane TMOS (C 21 H 46 O 3 Si). The modified material with TMOS disclosed good sorption capacities for dodecane (10.55 g/g) and motor oil (12.25 g/g). The retention profile test has revealed that about 1.06-14.91% of liquid hydrocarbons can be recovered by free drainage. The advanced recovery of oily liquids has been achieved by centrifugation technique being of 42.29-66.02%. Likewise, the hydrophobic aerogel (modified with TMOS) has showed a good sorption capacity for dodecane (9.24 g/g) in the presence of water (W-test). In addition, the clay aerogel polymer composites have been characterized by means of scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) technique.

Recently developed montmorillonite clay-based aerogels have attracted an attention owing to their highly porous internal structure. This study deals with the design of experiments applied for preparation of clay aerogel polymer composites and their testing and optimization for oil spill sorption. Three design variables have been chosen for experimentation, i.e. the amounts of montmorillonite (MMT), polyvinyl alcohol (PVA) and sodium dodecyl sulfate (SDS). Based on the experimental design the response surface models have been constructed. The objective for optimization was to maximize the performances of materials for sorption of dodecane and motor oil. To this end, the multi-objective optimization problem has been solved using NSGA-II optimization algorithm. The aerogel sorbent prepared under the optimal conditions of 2.109% w/v PVA, 2.678% w/v MMT and 0.210% w/v SDS bestowed the best sorption performance for both dodecane (23.63 g/g) and motor oil (25.84 g/g). Finally, the hydrophobic aerogel sorbent has been prepared using trimethoxy(octadecyl)-silane TMOS (C 21 H 46 O 3 Si). The modified material with TMOS disclosed good sorption capacities for dodecane (10.55 g/g) and motor oil (12.25 g/g). The retention profile test has revealed that about 1.06-14.91% of liquid hydrocarbons can be recovered by free drainage. The advanced recovery of oily liquids has been achieved by centrifugation technique being of 42.29-66.02%. Likewise, the hydrophobic aerogel (modified with TMOS) has showed a good sorption capacity for dodecane (9.24 g/g) in the presence of water (W-test). In addition, the clay aerogel polymer composites have been characterized by means of scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) technique.

Oil spills remain an inevitable risk in the exploration, production and transportation of hydrocarbons. Their impacts on the environment are usually severe, hence effective and efficient response strategies are essential to minimise environmental damage. Conventional synthetic oil sorbents are the most widely used sorbents for spill clean-up but are usually expensive and nonbiodegradable. Low-cost non-conventional biopolymeric sorbents are now emerging as alternatives to conventional sorbents used in oil spill clean-up owing to their availability and ecofriendliness. In this review, we present low-cost non-conventional cellulose and keratin based biopolymeric oil sorbents highlighting their oil sorption capacities, properties and mechanisms.

The oil industry is plagued with regular incidences of spills into the environment, causing environmental damage to flora and fauna, especially in marine environments where spills easily travel long distances from their sources. This study was carried out to investigate a simple two-step process for the conversion of waste cigarette filters into a superhydrophobic and oleophilic sorbent for application in oil/water separation and spill clean-up. Ultrasonically cleaned filters were surface modified by chemical vapour deposition using methyltrichlorosilane. The results show that the functionalised waste filters achieved superhydrophobic properties with a water contact angle of 154 ± 3.5°, adsorbing 16 to 26 times their weights in various oils, which is a better oil sorption performance than those of commercially available non-woven polypropylene adsorbents. Also, the sorption capacity did not significantly deteriorate after 20 cycles of reuse, with up to 75% sorption capacity retained...

The review article reflects on the potential of silica aerogel as viable absorbents for spilled crude oil. Reported oil absorption capacity of silica aerogel shows it has a future in polluted site clean-up. The review presents the various dynamics of oil spill, conventional clean-up technologies and silica aerogel synthesis techniques. It also highlights some investigations of oil spill sorption using aerogels. The future prospect of rice husk as a cheaper source silica aerogel is also considered.

Starting from TMOS and implementing co-gelation in the sol-gel method, silica was hybridized with an industrial formulation of bovine casein. The hybrid alcogels were dried in supercritical CO 2 to yield crack-free silica-casein aerogel monoliths of casein contents ranging from 4.7 wt% to 28 wt%. Cross-linked hybrid aerogels were produced from formaldehyde treated alcogels. The microstructures and the morphologies of the silica-casein aerogels highly resemble to that of pristine silica aerogels. The primary building blocks are spherical particles that interconnect into mesoporous networks (average d pore = 20 nm and S BET = 700 nm 2 /g), as shown by SEM, small-angle neutron scattering (SANS) and N 2 adsorption-desorption porosimetry. Contrast variation SANS experiments show that silica and casein form homogeneous nanocomposite backbones. The interaction of water with silica-casein aerogels was investigated by SANS, and by NMR cryoporometry, relaxometry and diffusiometry. Even when fully saturated with water, the hybrid silica-casein aerogels retain their original, highly permeable, open mesoporous structures that formed under supercritical drying. This represents a unique and advantageous wetting mechanism among hybrid inorganic-biopolymer materials, since the strong hydration of the biopolymer component often causes the deformation of the backbone and the consequent collapse of the porous structure. Silica-casein aerogels are biocompatible and inert for CHO-K1 cells.

A natural and biodegradable material that has good oil absorbtivity, high durability and reusability is one of the most demanded materials in the industry nowadays. It is believed to have potential to replace polypropylene function as the commercialized sorbent. One of material that suits this function is kapok fibre or commonly known as cotton. Using kapok, decomposition process, which always become an issue when dealing with polypropylene, is no more a problem. The nature of Kapok will allow it to decompose naturally without any harm threat to the environment. Besides, kapok has fibrous microstructure that becomes the key factor to absorb oil efficiently. Without any chemical modification, it can absorb significant amount of oil like polypropylene. This project was conducted to evaluate kapok capacity as the natural sorbent in terms of application. A series of test was done to analyze the surface microstructure, sorption capacity, dynamic oil retention and its reusability. Two experimental setups are prepared for sorption and desorption analysis. Findings of this paper are found base on the weight of oil recovered and HPLC test for seawater composition. It is believed that this project can prove the potential of Kapok as sorbent for oil spill cleanup at the end of this paper.

The durability and performance of specially developed restoration plasters or renders, are not always as good as expected. Salt crystallization is one of the causes of the observed degradation processes. To understand these processes in more detail, we investigated whether transport in the plasters depends on the masonry material. The transport of salt and moisture during drying of some plaster/substrate systems is followed with a Nuclear Magnetic Resonance technique. The observed differences in drying behaviour can be related to differences in pore structure between the plaster and substrate. For a good performance of the plaster a proper matching of its pore-size distribution with that of the masonry is required.

The size and distribution of pores have been studied through the melting behavior of water confined in white cement samples by ~H nuclear magnetic resonance cryoporometry. It is found that the sample cured at 298 K shows a considerably coarser pore structure in the range of pores from 1 to 15 nm when compared with the samples cured at 278 K. With the addition of the Sika Rapid 2 antifreeze admixture in the cement cured at 278 K, an increase of pores between 5 and 15 nm anda more homogeneous distribution of small pores from 1 to 5 nm is observed when compared with cement cured at the same temperature but without the antifreeze additive. The positive influence of Sika Rapid 2 antifreeze admixture on the mechanical properties of cement cured at a lower temperature was also found through the compressive strength measurements performed for the studied cement samples asa function of the cu¡ age.

Recently developed montmorillonite clay-based aerogels have attracted an attention owing to their highly porous internal structure. This study deals with the design of experiments applied for preparation of clay aerogel polymer composites and their testing and optimization for oil spill sorption. Three design variables have been chosen for experimentation, i.e. the amounts of montmorillonite (MMT), polyvinyl alcohol (PVA) and sodium dodecyl sulfate (SDS). Based on the experimental design the response surface models have been constructed. The objective for optimization was to maximize the performances of materials for sorption of dodecane and motor oil. To this end, the multi-objective optimization problem has been solved using NSGA-II optimization algorithm. The aerogel sorbent prepared under the optimal conditions of 2.109% w/v PVA, 2.678% w/v MMT and 0.210% w/v SDS bestowed the best sorption performance for both dodecane (23.63 g/g) and motor oil (25.84 g/g). Finally, the hydrophobic aerogel sorbent has been prepared using trimethoxy(octadecyl)-silane TMOS (C 21 H 46 O 3 Si). The modified material with TMOS disclosed good sorption capacities for dodecane (10.55 g/g) and motor oil (12.25 g/g). The retention profile test has revealed that about 1.06-14.91% of liquid hydrocarbons can be recovered by free drainage. The advanced recovery of oily liquids has been achieved by centrifugation technique being of 42.29-66.02%. Likewise, the hydrophobic aerogel (modified with TMOS) has showed a good sorption capacity for dodecane (9.24 g/g) in the presence of water (W-test). In addition, the clay aerogel polymer composites have been characterized by means of scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) technique.

Drying of masonry specimens was monitored by means of a two-dimensional (2D) magnetic resonance imaging (MRI) technique. The external surfaces stayed wet for longer if NaCl was present instead of pure water only. This corroborates many practical observations that salts aggravate dampness in masonry. A slower evaporation process and not hygroscopicity was the cause. That suggests that salt-induced dampness may, in general, arise simply from changes in the drying process of masonry materials. That also implies that the height and depth at which crystallization occurs in walls may depend on the relative equilibrium humidity (RHeq) and other properties of salts that influence drying of porous materials. Evaporation rates of free surfaces of pure water and saturated NaCl solution were measured by a gravimetric technique. The results indicate that slow drying of salt-contaminated materials is not due only to the lower RHeq of salt solutions. The effective surface of evaporation is likely to be reduced perhaps due to blocking of pores by salt crystals. Final salt-distribution maps of the specimens show that: (a) salts may affect the inner materials of the masonry, even in evaporation-induced processes that lead crystallization to occur predominantly on the external surface; (b) distinct internal distribution patterns occur if masonry composition varies.

Paints are widely used as finishing coats on all kinds of buildings. Aiming at a better understanding of how paints influence salt decay processes, experiments were performed on painted and unpainted specimens: (a) crystallization tests on specimens composed of a plaster on brick substrate; (b) drying experiments on stone specimens, monitored by means of a two-dimensional magnetic resonance imaging technique. The results of these experiments suggest that: (i) paints tend to increase the presence of moisture and salt deposition on or close to the surface of walls; (ii) the salt-accumulation behaviour and related features of different plasters/renders may be differently affected by paint layers.

The overall aim of this project is to develop a recyclable polymer aerogel for an effective utilization of plastic waste and to use it for oil clean up from wastewater. The waste utilization from one source (plastic waste) to reduce waste from another source (oil clean up from wastewater) will take the world one step closer to the sustainability. A huge proportion of municipal solid waste accumulated all over the globe is composed of plastic wastes and a large volume of it is either incinerated, disposed of into landfill or leaked into the ocean. The plastic leakage into the seawater has created further problems as around 13m tonnes of plastic is ingested by seabirds and fish. In addition, it is estimated that 20,000 plastic bottles are produced per second and less than 10% of them are recycled. With this rate, it is projected that if proper recycling measures are not taken then by 2050 ocean will contain more plastic by weight than fish.

Drying of masonry specimens was monitored by means of a two-dimensional (2D) magnetic resonance imaging (MRI) technique. The external surfaces stayed wet for longer if NaCl was present instead of pure water only. This corroborates many practical observations that salts aggravate dampness in masonry. A slower evaporation process and not hygroscopicity was the cause. That suggests that salt-induced dampness may, in general, arise simply from changes in the drying process of masonry materials. That also implies that the height and depth at which crystallization occurs in walls may depend on the relative equilibrium humidity (RHeq) and other properties of salts that influence drying of porous materials. Evaporation rates of free surfaces of pure water and saturated NaCl solution were measured by a gravimetric technique. The results indicate that slow drying of salt-contaminated materials is not due only to the lower RHeq of salt solutions. The effective surface of evaporation is likely to be reduced perhaps due to blocking of pores by salt crystals. Final salt-distribution maps of the specimens show that: (a) salts may affect the inner materials of the masonry, even in evaporation-induced processes that lead crystallization to occur predominantly on the external surface; (b) distinct internal distribution patterns occur if masonry composition varies.

h i g h l i g h t s For the first time, paper waste is converted into a green cellulose aerogel by an advanced and costeffective method. The material has high oil absorption capacities of 40-95 times of its weight. The material shows stable superhydrophobicity over five months. Cellulose fiber concentration affects significantly the oil absorption capability of aerogel. The maximum absorption capacity of the aerogel is achieved at 50°C.

Evaporative 3 cooling is a traditional strategy to improve summer comfort, which has gained renewed relevance in the context of the 6 transition to a greener economy. Here, the potential for evaporative cooling of two common porous building materials, natural stone and 7 ceramic brick, was evaluated. The work has relevance also to the protection of built heritage becauseevaporation underlies the problems of 8 dampness and salt crystallization, which are so harmful and frequent in this heritage. It was observed that the drying rate of the materials is, in 9 some cases, higher than the evaporation rate of a free water surface. Surface area measurements by a three-dimensional optical technique 10 suggested, as probable cause of this behavior, that surface irregularity gives rise to a large effective surface of evaporation in the material. 11 Surface temperature measurements by infrared were performed afterward during evaporation experiments outside during a hot summer day in 12 Lisbon. Their results indicate that ordinary building materials can be very efficient evaporative media and, thus, may help in achieving higher 13 energy efficiency while maintaining a simultaneous constructive or architectural function.

In this study, mixed oxides of Mn-Cu and Fe-Cu on OMS-2 support having an octahedral structure were synthesized by the refluxing and impregnation methods. The characteristics of the materials were analyzed by XRD, FTIR, SEM, EDX, and H2-TPR. In the CO oxidation test, CuFeOx/OMS-2 had slightly higher catalytic activity but is significantly more stable than CuMnOx/OMS-2 and CuO/OMS-2. Due to its lower reduction temperature in H2-TPR analysis, the Mars-Van-Krevelen mechanism for CuFeOx/OMS-2 (Cu2+–O–Fe3+ ↔ Cu+–□–Fe2+) could take place more energetically than CuO/OMS-2 and CuMnOx/OMS-2 (Cu2+–O2−–Mn4+ ↔ Cu+–□–Mn3+). In addition, the interaction between Fe and Cu in the catalyst could improve the durability of the surface oxides structure in comparison with that between Mn and Cu. With the high specific rate and TOF of 28.6 mmol/h.g and 0.508, respectively, CuFeOx/OMS-2 has a great potential as an effective catalyst for low-temperature oxidation application in CO and possible VOCs removal.

The effectiveness of polypropylene fibers as sorbents of oil-water emulsions was the object of the research in the present publication. Thus the sorption capacity of the synthetic material of the regional production with for emulsions of different concentration was investigated. Santrauka Straipsnyje nagrinėjama polipropileno pluošto naudojimo avarinionaftos išsiliejimo metu problema. Polipropileno pluoštasnaudojamas kaip naftą sugerianti medžiaga. Pateiktos skirtingostorio polipropileno pluošto išsiliejusios naftos sugeriamumosavybės.

Recently developed montmorillonite clay-based aerogels have attracted an attention owing to their highly porous internal structure. This study deals with the design of experiments applied for preparation of clay aerogel polymer composites and their testing and optimization for oil spill sorption. Three design variables have been chosen for experimentation, i.e. the amounts of montmorillonite (MMT), polyvinyl alcohol (PVA) and sodium dodecyl sulfate (SDS). Based on the experimental design the response surface models have been constructed. The objective for optimization was to maximize the performances of materials for sorption of dodecane and motor oil. To this end, the multi-objective optimization problem has been solved using NSGA-II optimization algorithm. The aerogel sorbent prepared under the optimal conditions of 2.109% w/v PVA, 2.678% w/v MMT and 0.210% w/v SDS bestowed the best sorption performance for both dodecane (23.63 g/g) and motor oil (25.84 g/g). Finally, the hydrophobic aerogel sorbent has been prepared using trimethoxy(octadecyl)-silane TMOS (C 21 H 46 O 3 Si). The modified material with TMOS disclosed good sorption capacities for dodecane (10.55 g/g) and motor oil (12.25 g/g). The retention profile test has revealed that about 1.06-14.91% of liquid hydrocarbons can be recovered by free drainage. The advanced recovery of oily liquids has been achieved by centrifugation technique being of 42.29-66.02%. Likewise, the hydrophobic aerogel (modified with TMOS) has showed a good sorption capacity for dodecane (9.24 g/g) in the presence of water (W-test). In addition, the clay aerogel polymer composites have been characterized by means of scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) technique.

In this study, zinc ferrite magnetic nanoparticles (ZnFe2O4, ZFO MNPs) were employed as a sorbent for the removal of oil spill from water surfaces. ZFO MNPs were synthesized via a sol-gel process and characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD). Both the apparent density and magnetic force were determined. ZFO MNPs presented a considerable magnetic force (40.22 mN) and an adequate density (0.5287 g/cm3), which are important for the magnetic separation and flotation. Four oil samples (gasoline engine oil, crude oil, used motor oil and diesel engine oil) were used to investigate the gravimetric oil removal capability of ZFO MNPs. The oil sorption capacities were found to be 23.00-6.13, 27.65-7.42, 22.62-7.01 and 30.54-9.93 g/g for crude, diesel engine, gasoline engine, and used motor oil, respectively. The current findings demonstrate that ZFO MNPs exhibit good properties (e.g., magnetic and density) and can be used as a sorbent fo...

This paper presents studies on the effect and capacity of lightweight expanded clay aggregates (LECA) as adsorbents for cleaning up crude oil from aquatic environment. These studies incorporate the effect of adsorbent particle size, surface modification, API (American Petroleum Institute) degree, and the contact time. Sorbent characterization has been determined using SEM, XRD, XRF, and BET. Optimum sorption was reached during the first 10 min, followed by a steady state of crude oil sorption. Furthermore, results indicated that fine LECA particles have higher adsorption efficiency due to the increase of specific surface area. Decreasing the API degree had a significant influence on the rise of the adsorption rate. The results indicated that the LECA performs better in heavier oil than lighter oil. Overall, LECA was found to be a proper adsorbent for cleanup oil spill from an aquatic environment, which could also be collected from the water surface rapidly.

In this study, zinc ferrite magnetic nanoparticles (ZnFe2O4, ZFO MNPs) were employed as a sorbent for the removal of oil spill from water surfaces. ZFO MNPs were synthesized via a sol-gel process and characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD). Both the apparent density and magnetic force were determined. ZFO MNPs presented a considerable magnetic force (40.22 mN) and an adequate density (0.5287 g/cm 3 ), which are important for the magnetic separation and flotation. Four oil samples (gasoline engine oil, crude oil, used motor oil and diesel engine oil) were used to investigate the gravimetric oil removal capability of ZFO MNPs. The oil sorption capacities were found to be 23.00-6.13, 27.65-7.42, 22.62-7.01 and 30.54-9.93 g/g for crude, diesel engine, gasoline engine, and used motor oil, respectively. The current findings demonstrate that ZFO MNPs exhibit good properties (e.g., magnetic and density) and can be used as a sorbent ...

ABSTRACTThere are few feasible options for sorbents, which can be quickly manufactured and deployed in the event of a major oil spill and so every oil spill is an ecological disaster. This paper aims to provide an understanding of what a realistic, full-scale crude oil spill solution would look like based on the performance of the best sorbents currently available, their costs, and their advantages.Adsorbent materials or “sorbents” described here have been a recent target for research toward applications in environmental cleanup, remediation, and hazardous material containment. These materials contain many compositions, syntheses, and practical manufacturing parameters that make most of them practically and logistically unfit to tackle quantities much larger than a single barrel of oil. Different properties of crude oil and nonpolar materials, such as their viscosity, density, and weathering, can also make these materials seem attractive on a lab scale but underperform in field test...

Salt crystallization is one of the main decay processes in historic masonry mortars, and climate change can worsen the salt weathering effects on those materials as result of, e.g., more often rain falls, more intense solar radiation and sea level rise. In this paper, the effectiveness and durability of a substitution “ventilated render” system (a two-layer render, with base and outer layer and “vertical grooves” in the base layer) on a full-scale salt laden masonry wall to reproduce conditions that may be found in real cases was investigated. The crystallization at the interface between render layers and in vertical grooves and the effect of the porous structure on salt crystallization were thoroughly investigated. It was highlighted the reliability of the results of the salt crystallization testing procedure on a full-scale masonry wall to attest the efficiency and durability of the render system. Finally, it was proven that the ventilated render system with water repellent in the...

Crude oil is a dark brown to black, naturally occurring viscous rock fluid obtained from the thermal and biological decay of plant and animal remains, in a process spanning millions of years [1]. Since crude oil was first discovered in commercial quantities, its production, processing, and worldwide distribution have been ever increasing. Crude oil is processed into a wide range of consumer and industrial products via a technique regarded as fractional distillation. This technique gives universally significant products such as gasoline, kerosene, petro-diesel and lubricating oil, and feed stocks or raw materials for petrochemical industries, such as ethylene and butylenes. The production, refining, and distribution of crude oil and products based on it involves a series of complex processes and procedures. A phenomenon referred to as “oil spill or spillage” usually arises in the course of undertaking these processes. Oil spill is a form of environmental pollution defined as the rele...

This paper is aiming to address the problem of oil spills occurring on water bodies. 81% of oil spills that occur are less than 50 US barrels in volume and these are considered as minor spills. There is no perfect solution for this problem and oil spills are a real threat to nature. As an alternative way of combating smaller scale oil spills, Exfoliated Graphite (EG) is being examined. Production temperature of Exfoliated Graphite is effective in the oil capturing capacity and it is covered by results gathered from tests. The higher the exfoliation temperature, the more surface area Exfoliated Graphite gains, so this large surface area makes it possible to capture petroleum products and hold it. To see the capturing efficiency of Exfoliated Graphite, motor oil, gasoline and diesel fuel mixture, Texas crude oil and Pennsylvania crude oil were used in the experiments. Also, the material was tried in fresh water and sea water. Additionally, a product is designed for real life applicati...

Conventional synthetic sorbents for oil spill removal are the most widely applied materials, although they are not the optimal choices from an economic and environmental point of view. The use of inexpensive, abundant, non-toxic, biodegradable, and reusable lignocellulosic materials might be an alternative to conventional sorbents, with obvious positive impact on sustainability and circular economy. The objective of this paper was to review reports on the use of natural-based adsorbing materials for the restoration of water bodies threatened by oil spills. The use of raw and modified natural sorbents as a restoration tool, their sorption capacity, along with the individual results in conditions that have been implemented, were examined in detail. Modification methods for improving the hydrophobicity of natural sorbents were also extensively highlighted. Furthermore, an attempt was made to assess the advantages and limitations of each natural sorbent since one material is unlikely to...

The catalytic combustion of ethyl acetate over prepared metal oxide catalysts was investigated. CeO, Co2O3, Mn2O3, Cr2O3, and CeO-Co2O3 catalysts were prepared on monolith supports and they were tested. Before conducting the catalyst experiments, we searched for the homogeneous gas phase combustion reaction of ethyl acetate. According to the homogeneous phase experimental results, 45% of ethyl acetate was converted at the maximum reactor temperature tested (350 • C). All the prepared catalysts were tested in order to find the best catalyst for the complete combustion of ethyl acetate. According to the results, all these catalysts produced higher conversion rates than that of the homogeneous experiment; however, none of the prepared catalysts resulted in complete combustion. The maximum conversion obtained with the CeO catalyst at 350 • C was 72%.