Papers by Yahya Muhammad Sani
Journal of the Nigerian society of chemical Engineers, Sep 30, 2021
This study investigated the degradation of methylene blue dye with ZnO-CuO/RHA, a synthesised agr... more This study investigated the degradation of methylene blue dye with ZnO-CuO/RHA, a synthesised agro waste-based photocatalyst under solar irradiation at ambient temperature. Preliminary screening of the methylene blue degradation facilitated the selection of the best ZnO-CuO/RHA combination. The photocatalytic degradation was done by taking varying weights of catalyst in 100 mL of dissolved 10-30 ppm MB solutions. The sample was magnetically stirred at 500 rpm in darkness before being exposed to sunlight irradiation. The suspension was magnetically stirred continuously and 5 ml was withdrawn intermittently, centrifuged and analysed with UV-Vis spectrophotometer. The effect of catalyst dosage, initial concentration and irradiation time on the photodegradation were studied using the one-variable-at-a-time method. The result showed that the degradation percentages of the catalyst with 1, 2, 3, 4, and 5 wt. % of RHA were 80.31%, 88.23%, 99.94%, 91.06 % and 81.12% respectively after 180 minutes. These results showed that degradation percentage was directly proportional to the irradiation time up to 3 wt. % thereafter, there was a decline in the percentage degradation. Hence, as the irradiation time increases, there was a significant increase in the degradation of methylene blue dye. ZnO-CuO/RHA catalyst was found to possess a higher photocatalytic activity in the presence of sunlight in comparison to bare ZnO-CuO since using RHA as a base for ZnO-CuO increased the surface area resulting in more active sites under visible light irradiation. ZnO-CuO/RHA may serve as an efficient-photocatalyst for industrial applications with excellent prospects.
JOURNAL OF THE NIGERIAN SOCIETY OF CHEMICAL ENGINEERS, 2021
This study investigated the degradation of methylene blue dye with ZnO-CuO/RHA, a synthesised agr... more This study investigated the degradation of methylene blue dye with ZnO-CuO/RHA, a synthesised agro waste-based photocatalyst under solar irradiation at ambient temperature. Preliminary screening of the methylene blue degradation facilitated the selection of the best ZnO-CuO/RHA combination. The photocatalytic degradation was done by taking varying weights of catalyst in 100 mL of dissolved 10-30 ppm MB solutions. The sample was magnetically stirred at 500 rpm in darkness before being exposed to sunlight irradiation. The suspension was magnetically stirred continuously and 5 ml was withdrawn intermittently, centrifuged and analysed with UV-Vis spectrophotometer. The effect of catalyst dosage, initial concentration and irradiation time on the photodegradation were studied using the one-variable-at-a-time method. The result showed that the degradation percentages of the catalyst with 1, 2, 3, 4, and 5 wt. % of RHA were 80.31%, 88.23%, 99.94%, 91.06 % and 81.12% respectively after 180 m...
Environmental Science and Pollution Research, 2021
Degradation of amines is a significant issue allied to amine-based carbon dioxide (CO 2 ) absorpt... more Degradation of amines is a significant issue allied to amine-based carbon dioxide (CO 2 ) absorption in post-combustion CO 2 capture. It becomes essential to have a detailed understanding of degradation products for advanced post-combustion CO 2 capture technology. Identification and quantification of degradation products of amines help in practicability and environmental assessment of amine-based technology. Gas, liquid, and ion chromatographic techniques are the benchmark tools for qualitative and quantitative analyses of the amines and their derivatives. Among others, gas chromatography has been more in use for this specific application, especially for the identification of degradation products of amines. This review focuses on the critical elucidation of gas chromatographic analysis and development of methods to determine the amine degradation products, highlighting preparation methods for samples and selecting columns and detectors. The choice of detector, column, sample preparation, and method development are reviewed in this manuscript, keeping in view the industry and research applications. Furthermore, obtained results on the quantitative and qualitative analyses using gas chromatography are summarized with future perspectives.
Green and Sustainable Chemistry, 2018
Biolubricant was synthesized from Cameroon palm kernel oil (PKO) by double transesterification, p... more Biolubricant was synthesized from Cameroon palm kernel oil (PKO) by double transesterification, producing methyl esters in the first stage which were then transesterified with trimethylolpropane (TMP) to give the PKO biolubricant in the presence of a base catalyst obtained from plantain peelings (municipal waste). The yields from both catalysts were significantly similar (48% for the locally produced and 51% for the conventional) showing that the locally produced catalyst could be valorized. The synthesized biolubricant was characterized by measuring its physical and chemical properties. The specific gravity of 1.2, ASTM color of 1.5, cloud point of 0˚C, pour point of -9˚C, viscosities at 40˚C of 509.80 cSt and at 100˚C of 30.80 cSt, viscosity index of 120, flash point greater than 210˚C and a fire point greater than 220˚C were obtained. This synthesized biolubricant was found to be comparable to commercial T-46 petroleum lubricant sample produced industrially from mineral sources. We have therefore used local materials to produce a biolubricant using a cheap base catalyst produced from municipal waste.
Journal of Environmental Chemical Engineering, 2018
The use of polymeric adsorbent for decontamination of various sources of water was critically rev... more The use of polymeric adsorbent for decontamination of various sources of water was critically reviewed. This arises from the alarming increase in water scarcity in many parts of the world due to increase in population, which exerts immense pressure on the available water resources. Treatment of wastewater, stormwater and seawater via series of technological pathways like adsorption, desalination, advanced oxidation and solid-phase microextraction constitute new strategies for removal of toxins, antibiotics, complex matrix samples, and heavy metals for sustainable production of potable drinking water. This study reviewed the use of polymeric adsorbents such as nano-magnetic polymers (NMPs), polysaccharides, extracellular polymeric substances (EPS), and covalent organic polymers (COPs) for effective decontamination of water. These materials were critically analyzed with emphasis on their characteristics, strengths, drawbacks, as well as the enhancement techniques. Furthermore, the mechanisms of adsorption involved were also discussed. This review shows that polymeric adsorbents have demonstrated remarkable removal efficiency for several contaminants.
Critical Reviews in Environmental Science and Technology, 2017
This study elucidates the recent trends in the formation, prevention, and removal of N-nitrosamin... more This study elucidates the recent trends in the formation, prevention, and removal of N-nitrosamines such as Nnitrosodimethylamine (NDMA) from wastewater or drinking water. Reports are rife on the occurrence of NDMA in areas such as amine degradation during postcombustion CO 2 capture (PCC), chlorinated/chloraminated and ozonated drinking water, smoked or cooked foods personal care, tobacco and pharmaceutical products. The major routes responsible for the formation of NDMA in portable waters include chlorination/ chloramination and ozonation. The major NDMA precursors are secondary, tertiary, and quaternary amines such as dimethylamine, diethanolamine, and triethanolamine. Due to the environmental and public health concerns posed by this contaminant, a proactive approach is necessary towards suppressing their occurrence, as well as their removal. Consequently, this study critically reviewed the formation, prevention, and removal of N-nitrosamines. The study discussed NDMA prevention techniques, such as physical adsorption, preoxidation, and biological activated carbon. The removal techniques discussed here include physicochemical (such as combined adsorption and microwave irradiation and UV photolysis), bioremediation, catalytic reduction, and dope technology. Irrespective of the effectiveness and seemingly economic viability of some of these technologies, preventing the occurrence of NDMA right from the outset is more potent because the treatments consume more energy.
Journal of Cleaner Production, 2017
Advanced Powder Technology, 2017
In this article, we investigated the optimum formulation towards synthesis of hierarchical nanopo... more In this article, we investigated the optimum formulation towards synthesis of hierarchical nanoporous 34 HY zeolites from acid activate kaolin. A central composite design (CCD) helped to investigate the influ-35 ence of aging (X 1 ), crystallization (X 2 ) and NaOH solution to kaolin ratio (X 3 ) on crystallinity (C%), specific 36 surface area (SSA) and hierarchical factor (HF). From the analysis of variance (ANOVA), we deduced that 37 all the process variables show statistical significance towards obtaining high C% and SSA while only X 3 is 38 statistically significant for optimal HF. The effectiveness of models was further evaluated using margin of 39 error and tolerance interval. The Optimum formulation for this hierarchical nanoporous HY zeolite was 40 obtained as 43.60, 64.23 and 6.97 for X 1 , X 2 , and X 3 , respectively. The developed models show that X 3 41 is the most statistically significant variable because it has the highest coefficient and the lowest 42 p-value in the entire model. These results give instrumental insight into the synthesis of hierarchical non-43 porous HY zeolite.
Journal of Cleaner Production, 2017
In this work, the transesterification of shea butter with MeOH over sulfated hierarchical nanopor... more In this work, the transesterification of shea butter with MeOH over sulfated hierarchical nanoporous Faujasite zeolite catalysts to produce biodiesel was studied. The sulfated faujasite zeolite was prepared from kaolin as the zeolite precursor and sulfuric acid as sulfate precursor. Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy show the successful anchoring of sulfate ions onto the faujasite zeolite. There was a remarkable improvement in the porosity and acid strength of the faujasite zeolite upon sulfation, though with a small reduction in density due to dealumination, which enhanced the stability. The synthesized sulfated zeolite is efficient for transesterification of shea butter and gives biodiesel yield of 96.89% at 200 C, 5:1 MeOH/oil, and 5 wt% catalyst for 3 h. The sulfated zeolite is stable after four consecutive cycle for a reaction that proceeds at 200 C, 5:1 MeOH/oil, 5 w% catalyst for 3 h and gave 90.76 w% in the first cycle while unsulfated zeolite gave a yield of 72.42% at the same condition due to diffusion limitation, crystal size and lower acid strength. This indicates that both pore structure and acid strength decide the activity of solid acids catalysts in biodiesel production.
Chemical Engineering Research and Design, 2013
On the basis of the perspective of wastes recycling and minimization of cost of phosphate removal... more On the basis of the perspective of wastes recycling and minimization of cost of phosphate removal via the chemical precipitation procedure, the present studies evaluated the ability of waste biogenic Gastropod shell to serve as a source of Ca 2+ ion in the removal and recovery of phosphate in calcium phosphate mineral (CPM) crystallization procedure. Phosphate removal efficiency values >99% was achieved when 2 g of snail shell was used in water of phosphate concentrations ranging between 25 and 1000 mg/L. pH and ionic strength exhibited no influence on the phosphate removal efficiency. Concomitant removal of phosphate and organic matter revealed that phosphate removal efficiency was not impacted but the magnitude of the organics removed increased with increase in the organic load. Kinetic analysis showed that second order kinetic model gave a better description of the process. XRD analysis of the derived sludge showed the crystallinity and peaks synonymous with the presence of whitlockite, hydroxyapatite and calcium phosphate hydrate. The FTIR of the sludge showed the disappearance of some naturally occurring functional groups and the appearance of phosphate peaks which confirmed the formation of CPM.
Applied Catalysis A: General, 2014
Homogeneous acid catalysts received wide acceptability because of their fast reaction rates. Howe... more Homogeneous acid catalysts received wide acceptability because of their fast reaction rates. However, postproduction costs incurred from aqueous quenching, wastewater and loss of catalysts led to the search for alternatives. Until recently, heterogeneous base catalyzed-biodiesel production also gained the attention of most researchers. This was because the process minimized the problems of homogeneous catalysis in terms of catalyst regeneration and recycling in continuous processes. However, despite these advances, the ultimate aim of producing biodiesel at affordable cost is yet to be realized. Further, the process requires refined feedstocks which account for as high as 88% of the final production costs. Thus, the focus of many research efforts is towards the rational design and development of solid acid catalysts aimed at reducing biodiesel production costs. Therefore, this study reviewed current literature on the activities and advantages of solid acid catalysts used in biodiesel production. It discussed in details how the preparation method and prevailing reaction conditions affect the catalytic activity of the catalyst. The review concluded by suggesting way forward from the traditional trial-and-error method to a rational means of determining catalytic activities.
Biodiesel - Feedstocks, Production and Applications, 2012
Comparative sustainability study of bioethanol production from selected starchy feedstocks that a... more Comparative sustainability study of bioethanol production from selected starchy feedstocks that are abundantly available was carried in this work. This is to ensure safe, reliable, and efficient production and consumption of fuel-grade bioethanol. The analysis utilized the established economic minimum bioethanol plant capacity of 158 000 m 3/annum. The processing flowsheet model utilized was the same for each feedstock. Economic, environmental and energy perspectives of the sustainability study were investigated. The economic and environmental indicators and indices were assessed using SuperPro® Designer and OpenLCA sustainability software packages respectively; exergy and lost work were estimated manually with Microsoft Excel (Microsoft Suite®). The economic sustainability indicator showed that the plants using cassava and sweet potato had the highest return on investment (ROI) of 64.41 and 41.96% respectively. The least profitable plant was based on sorghum recording ROI value of ...
RSC Advances, 2016
Biodiesel produced from triglycerides and/or free fatty acids (FFAs) by transesterification and e... more Biodiesel produced from triglycerides and/or free fatty acids (FFAs) by transesterification and esterification has attracted immense attention during the past decades as a biodegradable, renewable and sustainable fuel.
Energies, 2016
The environmental impact from the use of fossil fuel cum depletion of the known fossil oil reserv... more The environmental impact from the use of fossil fuel cum depletion of the known fossil oil reserves has led to increasing interest in liquid biofuels made from renewable biomass. This study presents the first experimental report on the catalytic pyrolysis of Napier grass, an underutilized biomass source, using ZSM-5, 0.3HZSM-5 and zinc exchanged zeolite-A catalyst. Pyrolysis was conducted in fixed bed reactor at 600˝C, 30˝C/min and 7 L/min nitrogen flow rate. The effect of catalyst-biomass ratio was evaluated with respect to pyrolysis oil yield and composition. Increasing the catalyst loading from 0.5 to 1.0 wt % showed no significant decrease in the bio-oil yield, particularly, the organic phase and thereafter decreased at catalyst loadings of 2.0 and 3.0 wt %. Standard analytical methods were used to establish the composition of the pyrolysis oil, which was made up of various aliphatic hydrocarbons, aromatics and other valuable chemicals and varied greatly with the surface acidity and pore characteristics of the individual catalysts. This study has demonstrated that pyrolysis oil with high fuel quality and value added chemicals can be produced from pyrolysis of Napier grass over acidic zeolite based catalysts.
RSC Advances, 2015
The paper reviewed the prospects of kaolinite application in catalysis and possible modification ... more The paper reviewed the prospects of kaolinite application in catalysis and possible modification strategy towards improving the catalytic properties.
Journal of the Taiwan Institute of Chemical Engineers, 2016
On the basis of the interplay between the metal function of oxo-anions, and structure of zeolites... more On the basis of the interplay between the metal function of oxo-anions, and structure of zeolites and its acidic properties, we report an innovative approach for enhancing acidity of sulfated zirconia, SZ. This concerns the superiority of SZ comprised of single-Brønsted acid sites dispersed on ZSM-5 over Ag, Ti and W. The influence of doping ZrO 2 on MFI framework of ZSM-5 was studied against other composite catalysts characterized by temperature-programmed desorption of ammonia (NH 3-TPD), IR spectra of pyridine adsorption, N 2 sorption, powder X-ray diffraction, elemental analysis via FE-SEM and EDX. Results showed uniform pore size, high mesopore volume, high surface area, and acid densities on the catalysts. Despite lower pore size distribution, Zr/ZSM-5 exhibited highest total acidity (0.75 mmol/g), and activity in converting >95% used frying oil (48 wt.%) over SZr/Ag, SZr/Ti, and SZr/W. This is outstanding considering the lower reaction parameter of 5 h, 5:1 methanol-to-oil ratio, and 200°C compared to prior arts. Evidently, structure and strength of Brønsted acids have direct effect on the catalytic activity of the materials. This study also illustrated prospects of converting wastes into biodiesel, which is important especially against the backdrop of the current plummeting price of Brent crude oil.
Journal of the Taiwan Institute of Chemical Engineers, 2016
Here, we report the upgrading of shea butter to biodiesel with hierarchical mesoporous ZSM-5 zeol... more Here, we report the upgrading of shea butter to biodiesel with hierarchical mesoporous ZSM-5 zeolites (HMZeol). Shea butter is a triglyceride (mainly oleic and steric acid) extracted from African shea tree nut. The catalysts synthesis was by desilication of conventional ZSM-5 with an aqueous solution of NaOH (0.3 and 0.4 M). XRF, XRD, NH 3-TPD and N 2 adsorption unveiled the effect of desilication of the parent zeolite. The study investigated the effect of NaOH concentration on matrix area, pore size, mesopore volume and Si/Al ratio. HMZeol showed superior activity on biodiesel yield when compared with the parent ZSM-5 zeolite. The catalytic material treated with 0.4 M NaOH (0.4HMZeol) gave 74% biodiesel yield at 5:1 methanol/oil molar ratio, 1 wt% catalyst, and 200 ᵒ C for 3 h reaction time while ZSM-5 gave 46.05% yield under the same reaction conditions. Further increase in the reaction time to 12 h for 0.4HMZeol, 0.3HMZeol and ZSM-5 gave 82.12, 79.21, and 72.13% biodiesel yield respectively. These results showed that hierarchical mesoporous HZSM-5 is a promising solid acid catalyst for biodiesel production via methanolysis.
Journal of the Taiwan Institute of Chemical Engineers, 2016
Highly efficient, robust and mesoporous sulfated zirconia, SZ catalysts were prepared by co-preci... more Highly efficient, robust and mesoporous sulfated zirconia, SZ catalysts were prepared by co-precipitation and incipient-wetness routes with sufficient and in-excess acid. The study investigated the effect of pH, precursor type, and concentration, on SZ and compared their acidity and performance with ytterbium-doped SZ toward transesterification. N 2 sorption, elemental analysis, XRD, and ammonia temperature-programmed desorption (NH 3-TPD) revealed the properties of the catalytic materials. The specific surface area increases independently of the presence of Ti up to 60.33 m 2 /g, with increasing pH while pore size of the tetragonal crystallites decreases from 37.04 to 6.83 nm. Soaking the material in sufficient 0.5-M H 2 SO 4 produced 37.04 nm S BET in contrast to 21.21 nm from soaking in excess. Double sulfation ensured sulfate incorporation while moderate precursor amounts enhanced activity of the materials. Interestingly, despite low specific surface area, which was due to short aging period, large mesoporosity, high amount, and dispersion of active sites on Yb-doped SZ, SZr-Ti-Yb-500-4/s ensured remarkable activity. The catalyst converted ca. 99% of used frying oil containing ca. 48 wt. % FFA. Consequently, this highlights the prospect of producing biodiesel at lower cost especially with current dwindling price of crude oil.
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Papers by Yahya Muhammad Sani