Ethyl-2-amino-4-[(4-chlorophenyl)carbamoyl]-5-methylthiophene-3-carboxylate and ethyl-2-amino-4-[... more Ethyl-2-amino-4-[(4-chlorophenyl)carbamoyl]-5-methylthiophene-3-carboxylate and ethyl-2-amino-4-[(2,4dimethylphenyl)carbamoyl]-5-methylthiophene-3-carboxylate were synthesized by the reaction of sulphur, ethylcyanoacetate with 4-chloroacetoacetanilide and N-(2,4-dimethylphenyl)-3-oxobutyramide respectively. The highly versatile aminothiophenes obtained were diazotized and coupled with various N-phenylmaleimides in the presence of fused sodium acetate, furnished a series of new monoazo disperse dyes. The dyeing performance of these dyes was assessed on polyester fabric by dyeing with the aid of a carrier and also under reduced pressure. These dyes were found to give yellow, deep pink, brown and brownish purple shades with very good levelness on the polyester fabric. Fastness properties of the dyed fabrics were measured and most of the dyed fabrics tested displayed very good wash, perspiration, sublimation and rub fastness ratings, however they had poor photostability. The fabrics dyed under pressure showed deeper hue of the colours even after washing.
Thevetia Nerrifolia and Jathropha Curcas seed oils were extracted from their oil seeds by soxhlet... more Thevetia Nerrifolia and Jathropha Curcas seed oils were extracted from their oil seeds by soxhlet extraction using petroleum ether (40-60 o C) as solvent. The oils were characterized and the oil yield, refractive index, acid value, saponification value, iodine value, colour and relative density were found to be 47.77%, 1.464, 4.365 (mg/KOH), 125.62 (mg/KOH), 98.48 (wij), 4 + and 0.926 for Thevetia Nerrifolia seed oil and 46.56%, 1.496, 33.65 (mg/KOH), 175.12 (mg/KOH) 105.43 (Wij), 3 and 0.913 for Jathropha Curcas seed oil respectively. Dimer acids were prepared from these seed oils by heating 200g of each of the oils under nitrogen inert atmosphere in a four necked resin kettle at a temperature of 300 o C for 12 hours. The physicochemical properties of the dimer acids were analyzed and were found to compare favourably with each and other well known feed stocks of dimerization.
Penta-erythritol, melamine and diammonium hydrogen orthophosphate were doped into emulsion paint ... more Penta-erythritol, melamine and diammonium hydrogen orthophosphate were doped into emulsion paint and painted into some tropical woods that are commonly used for building, furniture, and other construction. These woods are Daniellia oliveri , Anogeissus leiocarpa , Mansonia altissima and Vitex doniana . The woods were also doped with a combination of urea fertilizer and alum dissolved in water. Paint formulations were prepared by using a combination of penta-erythritol, melamine and diammonium hydrogen orthophosphate and alone with gypsum. Some woods were painted with the formulations. The flame retardation effects of each of these formulations on the combustion of these tropical woods were determined through the following combustion parameters; ignition time, flame time, after glow, char length, flame propagation rate, moisture content and percent add-on. It was observed that the flame retardants really had retardation effect on the combustion of these tropical woods. The order of t...
Physiochemical, Mineralogical, Thermal and Kinetic Characterisation of Selected Coals from the Benue Trough and Anambra Basin, Nigeria
Coke and Chemistry
This study examined the physiochemical, mineralogical, thermal, and kinetic characteristics of se... more This study examined the physiochemical, mineralogical, thermal, and kinetic characteristics of selected Nigerian coals, namely; Chikila (CHK), Lafia Obi (LFB) and Okaba (OKB) from the Benue Trough and Anambra Basin. Physicochemical analyses revealed significant carbon, volatile matter, fixed carbon, and higher heating values (~25–30 MJ/kg) along with low contents of moisture and ash. The deduced properties indicate subbituminous to bituminous rank coals. The morphological, microstructure and elemental analyses revealed heterogeneous sized coal particles with a glassy lustre, which are ascribed to quartz, alumina, kaolinite, hematite, and other clay or aluminosilicate minerals. Thermal analysis under oxidative conditions indicated the coal samples are highly reactive, which resulted in significant degradation as evident in the high mass losses (ML = 91.59–94.04)% and low residual masses (RM = 5.96–8.41)%, which occurred in the order LFB > OKB > CHK for ML whereas RM was CHK > OKB > LFB. Kinetic analysis values of activation energy (Ea) from 30.07 to 43.91 kJ/mol, frequency factor (A) from 1.16 × 10–02 to 6.73 × 10–02 min–1 and R2 from 0.98–0.99 based on the Coats–Redfern model. The kinetic analysis indicated the coals are highly reactive and suitable for energy recovery.
International Journal of Chemistry and Materials Research, 2015
Thermochemical decomposition of Ondo tar-sand was carried out at a temperature of between 190-250... more Thermochemical decomposition of Ondo tar-sand was carried out at a temperature of between 190-250°C in a constructed metal retort, and a yield of 66.66 % bitumen was obtained. Some important parameters of coal for blend simulation, such as the rheological and agglomerating properties of coal samples from-Garin Maiganga (GMG), Chikila (CHK), Lamza (LMZ), Shankodi-Jangwa (SKJ), Afuzie (AFZ) were determined by Gray-King assay test to assess their suitability for blending in coke making. The results showed that all the coals had poor thermoplastic properties that cannot agglomerate on heating because of their low level of fluidity, even though SKJ had an appreciable coke yield of 82.60 % with coke type C indicating that it was weakly coking. Thereafter, formulation of binary blend of coal-bitumen by weight (10 % bitumen and 90 % pre-heated coal samples at about 150 o C) was carried out. And the feasibility of the blend for industrial coke production was investigated by physico-chemical analysis, which revealed that the coking properties of the blend had been improved: Gieseler fluidity/plastic property in dial division per minute (DDPM) for LMZ = 76; CHK = 15; AFZ = 37; GMG = 18 and SKJ = 390, which might produce metallurgical coke with good chemical and mechanical properties.
Despite Nigeria's vast mineral and energy resources, the nation lacks su cient electricity genera... more Despite Nigeria's vast mineral and energy resources, the nation lacks su cient electricity generation capacity to stimulate sustainable growth and infrastructural development. However, the discovery of vast coal deposits across the nation's sedimentary basins could provide cheap, reliable, and abundant energy supplies. However, the lack of comprehensive data on the fuel characteristics, energy recovery, and potential emissions of Nigeria's coals currently hampers the quest for coal-red electricity generation. Hence, this study examined the physicochemical, microstructural, mineralogical, and thermal fuel properties of three (3) newly discovered coals from Akunza (AKZ), Ome (OME), and Shiga (SHG) in Nigeria for potential energy recovery through combustion and pyrolysis. Physicochemical analysis revealed high combustible but low levels of polluting elements. The higher heating values ranged from 18.65 MJ/kg for AKZ to 26.59 MJ/kg for SHG. Microstructure analysis revealed rough textured and surfaced particles with a glassy lustre ascribed to metals (such as Ti and Fe), quartz, and kaolinite. Mineralogical analyses revealed the major elements (C, O, Si, and Al), along with minor (Ca, Cu, Fe, K, Mg, S, and Ti) associated with clays, salts, or the porphyrin constituents of coal. Thermal analysis showed mass losses (M L) ranging from 30.51% to 87.57% and residual mass (R M) from 12.44% to 69.49% under oxidative (combustion) and non-oxidative (pyrolysis) conditions due to the thermal degradation of organic matter and macerals (vitrinite, inertinite and liptinite) during TGA. Overall, the coals are potential feedstocks for energy recovery through pyrolysis and combustion.
Nigeria is endowed with large deposits of high grade iron ore but reserves of suitable coking coa... more Nigeria is endowed with large deposits of high grade iron ore but reserves of suitable coking coals are extremely meager necessitating looking into the option of utilising lower rank coals. In this work, the properties of three Nigerian coals (Onyeama, Lafia-Obi and Garin Maiganga), are investigated to determine their suitability in developing formed coke for use as blast furnace coke. Parameters that were used include the shatter index, expressed as percentage stability and friability and micum index. The highest cummulative percentage stability and the lowest cummulative percentage friability was observed in Lafia-Obi with values of 67.54% and 32.46%, followed by Onyeama with 66.92% and 33.08% and then Garin Maiganga with 55.04% and 44.96% respectiely. Medium and low temperature carbonization of Onyeama and Lafia-Obi coal samples gave an improved and satisfactory percentage stability and friability for the semi-cokes. The percentage stability and friability are indicators of charg...
Rare earth elements study of Cretaceous coals from Benue Trough basin, Nigeria: Modes of occurrence for greater sustainability of mining
The rare earth elements (REE) possess a beneficial combination of chemical and physical propertie... more The rare earth elements (REE) possess a beneficial combination of chemical and physical properties, making them valuable for most advanced branches of engineering and technology. Alternative sources of REE are desirable due to limited reserves of conventional REE containing minerals over the world combined with disproportionate supply over demand in the commodity markets. This study investigated the occurrence of REE and carbon nanotubes (CNTs) in Cretaceous Nigerian coals for prospective industrial applications. Results show that the coals’ crystalline mineral matter comprises quartz, kaolinite, and illite with minor quantities of feldspar, hematite, magnetite, calcite, dolomite, which indicate detrital mineral origins. Elemental relationships (such as Al2O3/TiO2, Cr/Th vs. Sc/Th, and Co/Th vs. La/Sc) suggest sediment-source regions with mafic, intermediate or felsic compositions. REE are either strongly fractionated or characterized by light-enrichment along with outlook coefficie...
Journal of Minerals and Materials Characterization and Engineering, 2011
Two Nigerian coals, Lafia-Obi and Chikila were blended in the mass ratio of 70:30 with imported A... more Two Nigerian coals, Lafia-Obi and Chikila were blended in the mass ratio of 70:30 with imported American and Polish coking coals. Proximate analysis, free swelling index, Ruhr dilatometer and Gieseler plastometer were used in assessing the coking qualities of both the single coals and the blends. The results show that the blends are lower in moisture and ash contents; higher in volatile matter and fixed carbon than the single Nigerian coals. The rheological parameters revealed superiority in thermoplastic properties of the blends over the unblended local coals. Lafia-Obi/Foreign coals blends possess lower ash and better rheological properties compared to Chikila/Foreign coal composites which have high ash and poor rheological properties. These together suggest that amongst the two Nigerian coals, Lafia-Obi is superior for blending with the foreign ones in metallurgical coke production.
The suitability of coal for any application depends on its rank and other quality parameters. Suc... more The suitability of coal for any application depends on its rank and other quality parameters. Such information on Benue trough coals is either lacking or inadequate. Recent studies have shown that there are more deposits of coal in Nigeria than have previously been documented. The few exploited deposits are mainly used for combustion purposes. Despite the reported occurrences of other Nigerian coal deposits such as Lamza, Doho and Kumo, information regarding their investigation is rare. Therefore, part of the current challenge is to assess the quality of these coal deposits, determine their hydrocarbon-generative potentials, and find applications for the samples. This book therefore provides detailed Organic Geochemical studies of Benue Trough Coals and some of their applications. The studies combine proximate analysis, coal petrography, biomarkers and rock-eval pyrolysis in the assessment of the hydrocarbon source rock and coking potentials of the coals. The book is intended for re...
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