Ganpat Choudhary

Bio: Ganpat Choudhary is an academic researcher from Indian Institute of Technology, Jodhpur. The author has contributed to research in topics: Spinel & Fluoride. The author has an hindex of 7, co-authored 14 publications receiving 117 citations.

Ni/Co-Natural Clay as Green Catalysts for Microalgae Oil to Diesel-Grade Hydrocarbons Conversion

Abstract: The Ni/Co-natural clay catalysts have been prepared for the conversion of algae oil into diesel-grade hydrocarbons. Methyl oleate was used as a model compound for the present study. Ni/clay catalyst promotes decarboxylation/decarbonylation, whereas remarkable selectivity in hydrodeoxygenation (HDO) is achieved with Co/clay catalysts. Powder XRD and DRS studies of substrate mixed catalysts reveal a more prominent adsorption of substrate molecules over the Ni surface, which results in low HDO selectivity of nickel catalysts by surpassing the essential contribution of acidic sites. The HDO process provides higher carbon atom economy and energy value over decarboxylation/decarbonylation, while further reducing the formation of greenhouse gases such as CO2 and CH4. Total yield of saturated hydrocarbons from algae oil was 84–86 wt % with similar selectivity. The HDO rates of different fatty acids present in algae oil were independent of the fatty acid chain length. The catalysts are cost-effective and recyclabl...

On the investigation of acid and surfactant modification of natural clay for photocatalytic water remediation

Abstract: In this study, a series of mineral and organic acids are introduced to natural clay modification. Several analytical techniques are employed to identify the physical and chemical changes in clay. The effect of surfactants on these properties is also investigated. The samples are prepared using simple acid treatment without filtration. The alteration in surface morphology is proportional to the acid strength as evident from SEM and XRD analyses. Therefore, the treatment with mineral acid and organic acid/HNO3 results in the formation of new layers by surface modification as depicted in SEM images, and a higher degree of suppression in characteristic XRD reflections of clay is noticed. However, the treatment with organic acids modifies the existing interlayer spacing of clay, and therefore, the XRD characteristic reflections of clay are less affected. These observations are also supported by FT-IR analysis. The surface area of modified clay is dependent on the acid strength, composition and size of counter-anion of acid. An increase in surface area and porosity is noticed after surfactant modification of HNO3-treated clay, where the change is more prominent at the concentration higher than their respective critical micelle concentration. Thermal stability is dependent on the chemical composition and surface area of clay materials. A relatively higher absorbance is observed for modified clay materials compared with untreated clay during DRS analysis. The catalytic efficiency of modified clay materials in Eriochrome Black T degradation has been demonstrated.

Improved electrochemical performance of rare earth doped LiMn1.5-xNi0.5RExO4 based composite cathodes for lithium-ion batteries

Abstract: LiMn1.5Ni0.5O4 with spinel type of structure was synthesized by sol-gel method and doped by different rare-earth elements (Nd, Gd and Dy). It was found that the inclusion of rare-earth element preserves the cubic spinel structure, leads to smaller particle size and improves the cyclic performance of the produced batteries. The best battery performance was obtained after doping the spinel structure by Gd. Among the used rare-earth elements Gd is the only one with stable oxidation state of 3 + which leads to stabilization of the Mn dissolution. Thus, the improvements observed in battery performance (rate performance and cycle life) are due to the superior structural stability of the doped active materials. It is concluded that the LiMn1.48Ni0.5Gd0.02O4 sample is the one with the best overall performance to act as active material for cathodes in rechargeable lithium-ion batteries.

Sulfonated poly ether sulfone/heteropoly acid composite membranes as electrolytes for the improved power generation of proton exchange membrane fuel cells

Abstract: The organic/inorganic hybrid membranes consisting of different concentrations of phosphotungstic acid (PWA) in sulfonated poly ether sulfone (SPES) were constructed for the usage as electrolyte in proton exchange membrane fuel cells (PEMFCs). The repulsion applied between the hydrophilic moieties of host and guest components resulted in the porosity of prepared composite membranes. The as-made membranes demonstrated the prompt thermal stability and validated its applications in elevated temperature operation of PEMFCs. When the concentration of PWA was increased to 30 wt% in sulfonated polyether sulfone, the ionic conductivity of the corresponding membrane was increased to 19 mS/cm at room temperature, presumably due to the inherent conductivity of the PWA molecules and the enhanced acidity of sulfonic acid groups in the membranes. The SPES/PWA composite membrane (IEC 1.74 meq/g) comprising 30 wt% of PWA exhibited a maximum ionic conductivity of 116 mS/cm at 90 °C under 100% relative humidity (RH). The as-made SPES/PWA-30 composite membrane exhibited the maximum PEMFC power density of 305 mW/cm2, which validated its potential applications in PEMFCs.