Sustainable biofuel synthesis from non-edible oils: a mesoporous ZSM-5/Ni/Pt catalyst approach.

This work examines the hydrodeoxygenation (HDO) activity of non-edible oils using a high surface area catalyst. The HDO activity was thoroughly examined and contrasted using the high surface area catalyst Ni/Pt-ZSM-5 as well as other supports like MCM-48 and H-beta. Ni/Pt bimetals supported on mesoporous ZSM-5 were created via reverse order impregnation to facilitate HDO of non-edible oils. Techniques such as XRD, FT-IR, BET, HR-TEM, HR-SEM, TPD, and TGA were used to characterize the produced catalysts. The synthesized catalysts considerably influenced the hydrodeoxygenation activities for the synthesis of lengthy chain hydrocarbons in a stainless-steel reactor with a high-pressure fixed bed between 300 and 375 °C under 10-40 bar hydrogen pressure. High levels of Ni/Pt-ZSM-5 acidity, textural, and H2 consumption qualities were discovered. Distributions of the products were also reviewed, along with comparisons of the structure-activity connections.

Ni-Fe bimetallic catalysts with high dispersion supported by SBA-15 evaluated for the selective oxidation of benzyl alcohol to benzaldehyde.

A wetness impregnation method was used to impregnate the substrate with a substantial quantity of oleic acid together with a metal precursor, leading to significantly dispersed Ni-Fe bimetallic catalysts based on mesoporous SBA-15. Using a wide variety of characterization methods, such as XRD, BET, and TEM Analysis, the physiochemical properties of the catalyst were determined. The addition of the metal does not have any effect on the structural characteristics of the SBA-15 catalyst, as validated by transmission electron microscopy (TEM), which shows that the prepared SBA-15 supported catalyst has a hexagonal mesoporous structure. The catalytic capabilities of the Ni-Fe-SBA-15 catalysts were evaluated in the conversion of BzOH using tert-butyl hydroperoxide (TBHP) as an oxidant and acetonitrile as a solvent. The Ni/Fe-SBA-15 (NFS-15) catalytic composition is the best of the developed catalysts, with a maximum conversion of 98% and a selectivity of 99%. In-depth investigations were conducted into the molar ratio of TBHP to BzOH, the dosage of the catalyst, the reaction rate, temperature, and solvent. The recycling investigations indicate that the synthesized Ni/Fe-SBA-15 (NFS-15) catalyst seems to be more durable up to seven successive cycles.

Correlation between the particle size, structural and photoluminescence spectra of nano NiCr2O4 and La doped NiCr2O4 materials.

Nano NiCr2O4 undoped and La doped NiCr2O4 nanorods array were successfully prepared by solution based conventional method[sbcm]. The synthesized samples were characterized by the diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) spectroscopy for finding optical properties. Further, the samples structure confirmed by Fourier transforms infrared (FTIR), and X-ray diffraction (XRD)techniques. High-resolution transmission electron microscopy (HRTEM) analysis revealed the attachment of NiCr2O4 nanorods on surface of nanoparticles. From the results, it was found that the reaction time, band gap energy, and particle size strongly influenced by changing the concentration of La in NiCr2O4. This work is notable for its examination of the impact of the precursor on the optical and structural characteristics of samples of La-doped and undoped NiCr2O4. This was the first time the investigation had been done. The average particle size of the La-doped and undoped NiCr2O4 samples is between 16 and 24 nm.

Comparative risk assessment studies estimating the hazard posed by long-term consumption of PPCPs in river water.

This study assesses the risk due to Emerging Contaminants (ECs), present in Indian rivers - Ganga (650 million inhabitants), Yamuna (57 million inhabitants), and Musi (7,500,000 inhabitants), 13 ECs in total, have been used for risk assessment studies. Their concentrations (e.g., Fluconazole: 236950 µg/l, Ciprofloxacin: 31000 µg/l, Caffeine: 21.57 µg/l, etc.) were higher than the threshold concentrations for safe consumption (e.g. Fluconazole allowable level is 3.8 µg/l, and Ciprofloxacin allowable level is 0.51 µg/l). Three different pathways of emerging contaminants (ECs) transfer (oral water ingestion, oral fish ingestion, and dermal water contact) have been considered and the study is carried out in 2 ways: (i) deterministic and (ii) probabilistic approaches (using Monte Carlo iterative methods with 10000 simulations) with the aid of a software - Risk (version 7.5). The risk value, quantified by Hazard Quotient (HQ) is higher than the allowable limit of 1 for several compounds in the three rivers like Fluconazole (HQ = 18276.713), Ciprofloxacin (HQ = 278.675), Voriconazole (HQ = 14.578), Cetirizine (HQ = 1006.917), Moxifloxacin (HQ = 8.076), Caffeine (HQ = 55.150), and Ibuprofen (HQ = 9.503). Results show that Fluconazole and Caffeine pose the maximum risk in the rivers via the "oral pathway" that allows maximum transfer of the ECs present in the river (93% and 82% contribution to total risk). The risk values vary from nearly 25 times to 19000 times the United States Environmental Protection Agency (USEPA) threshold limit of 1 (e.g., Caffeine Infant Risk = 25.990 and Fluconazole Adult Risk = 18276.713). The most susceptible age group, from this study, is "Adults" (19-70 years old), who stand the chance of experiencing the adverse health hazards associated with prolonged over-exposure to the ECs present in the river waters. Musi has the maximum concentration of pollutants and requires immediate remediation measures. Further, both methods indicate that nearly 60-70% of the population in all the three study areas are at risk of developing health hazards associated with over-exposure to ECs regularly, making the areas inhabitable.

Isomerization of C7 and C8 through Ionic Liquids Supported by a Fe/SBA-15 Catalyst.

Isomerization is extensively utilized in the petroleum industry, and this study demonstrates an energy-efficient process utilizing an ionic liquid catalyst. 1-Ethyl-3-methylimidazolium triflate [Emim][TFO] as an ionic liquid was immobilized on solid support Fe/SBA-15. Variants of the catalyst were developed with the Fe constant at 5% and different ratios of ionic liquid. In the catalyst Fe/[Emim][TFO]/SBA-15, the metal Fe was loaded via the impregnation method, and subsequently, the ionic liquid variants Fe/[Emim][TFO](10)/SBA-15, Fe/[Emim][TFO](20)/SBA-15, and Fe/[Emim][TFO](30)/SBA-15 were synthesized. The physical properties of the synthesized catalyst were studied using standard characteristic techniques. The process performance was studied for variants of each parameter, which include temperature, hydrogen flow rate, pressure, and weight hourly space velocity. The iso-products of n-heptane and n-octane were obtained with an appreciable conversion of >90% and a selectivity of >95% with the catalyst Fe/[Emim][TFO](20)/SBA-15 among the other synthesized catalysts. The process yielded a high quantum of iso-products with negligible cracked products at a low temperature of 140 °C. The catalyst Fe/[Emim][TFO](20)/SBA-15 at 140 °C delivered the highest yield of iso-alkanes among the three catalysts. Iso-alkanes are instrumental tools for increasing the octane number of a fuel. This study delivers high iso-alkane content fuel, which can provide the best anti knock capability and enhance fuel efficiency for the life of modern high-powered engines. The results demonstrate a process that is energy-efficient, economic, and environmentally friendly.

Long-term impacts of climate change on coastal and transitional eco-systems in India: an overview of its current status, future projections, solutions, and policies.

Urbanization and industrial development are increasing rapidly. These are accompanied by problems of population explosion, encroachment of agricultural, and construction lands, increased waste generation, effluent release, and escalated concentrations of several greenhouse gases (GHGs) and pollutants in the atmosphere. This has led to wide-scale adverse impacts. Visible effects are fluctuations in temperatures and precipitation, rising sea levels, unpredictable floods, storms and cyclones, and disruption to coastal and transitional ecosystems. In a country like India with a massive population of nearly 1.4 billion and around 420 million people dwelling on or near the coasts, this effect is pre-dominant. India has extensive coastlines on both sides that are subject to greater contact and high impact from the water bodies. The factors impacting climate change, its consequences, and future predictions must be analyzed immediately for implementing precautionary measures to ameliorate the detrimental effects. Several endemic species have been endangered as these changes have resulted in the loss of habitat and interfered with the food webs. Climatic impacts on transitional ecosystems also need to be considered to preserve the diversity of each. The cooperation of governmental, independent organizations and policymakers throughout the world is essential to control and mediate the impacts on health, agriculture, and other related sectors, the details of which have been elaborated in this review. The review analyses the trends in climatic variation with time and discusses a few extremities which have left permanent effects on the population primarily concerning the coastal - Indian scenario and its eco-systems.

Cytotoxic, Antidiabetic, and Antioxidant Study of Biogenically Improvised Elsholtzia blanda and Chitosan-Assisted Zinc Oxide Nanoparticles.

In the present study, we have improvised a biogenic method to fabricate zinc oxide nanoparticles (ZnO NPs) using chitosan and an aqueous extract of the leaves of Elsholtzia blanda. Characterization of the fabricated products was carried out with the help of ultraviolet-visible, Fourier transform infrared, X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, selected area electron diffraction, and energy-dispersive X-ray analyses. The size of the improvised ZnO NP measured between 20 and 70 nm and had a spherical and hexagonal shape. The ZnO NPs proved to be highly effective in the antidiabetic test as the sample showed the highest percentage of enzyme inhibition at 74% ± 3.7, while in the antioxidant test, 78% was the maximum percentage of 2,2-diphenyl-1-picrylhydrazyl hydrate scavenging activity. The cytotoxic effect was investigated against the human osteosarcoma (MG-63) cell line, and the IC50 value was 62.61 µg/mL. Photocatalytic efficiency was studied by the degradation of Congo red where 91% of dye degradation was observed. From the various analyses, it can be concluded that the as-synthesized NPs may be suitable for various biomedical applications as well as for environmental remediation.

Combustion and emission analysis of hydrogenated waste polypropylene pyrolysis oil blended with diesel.

Petroleum-based plastic pyrolysis oil contains unsaturated compounds, and the presence of these compounds makes the produced fuel unsuitable for combustion in diesel engines. Hydrogenation of pyrolysis oil is performed to convert unsaturated compounds to saturated compounds. Past studies have shown that hydrogenation of petroleum-based plastic pyrolysis oil is viable; however, its combustion and emissions analysis in diesel engines has not yet been reported. In this study, we investigated the combustion, performance, and emissions of hydrogenated polypropylene pyrolysis oil (HPPO) blended with diesel. Polypropylene (PP) was converted to pyrolysis oil using ZSM-5 as the catalyst. The hydrogenation of polypropylene pyrolysis oil (PPO) was conducted at pressure of 70 bar, and the reaction temperature was maintained at 350 °C. Ni metal impregnated on the ZSM-5 base support was used as the catalyst of choice. The produced HPPO possessed physicochemical properties that match the EN590 standards(European diesel fuel standards). Gas chromatography-mass spectrometry (GC-MS) studies of PPO and HPPO showed the effectiveness of hydrogenation for the complete conversion of alkenes to alkanes, and hydrocracking resulted in cracking higher carbon number alkanes to lower values. HPPO was blended with diesel in ratios of 10 wt.%, 20 wt.%, 30 wt.%, and 40 wt.%. The diesel engine performance results for the blended fuel showed combustion, performance, and emissions on par with pure diesel fuel for blending ratios up to 20 wt.%. As is known, plastic solid waste (PSW) materials pose serious hazards to the environment. Our HPPO physicochemical properties matched the EN590 standards for diesel fuel. The combustion of HPPO in diesel engines can provide an option for environmentally cleaner disposal of PSW.

Recent advances in the synthesis and applications of mordenite zeolite - review.

Among the many industrially important zeolites, mordenite is found to be interesting because of its unique and exceptional physical and chemical properties. Mordenite (high silica zeolite) is generally prepared by the hydrothermal method using TEA+ cations. TEA+ cations are the best templating agent, though they can create a number of issues, for instance, generating poison and high manufacturing cost, wastewater contamination, and environmental pollution. Hence, it is necessary to find a mordenite synthesis method without using an organic template or low-cost template. In this review, a number of unique sources were used in the preparation of mordenite zeolite, for instance, silica sources (rice husk ash, silica gel, silica fumes), alumina sources (metakaolin, faujasite zeolite) and sources containing both silica and alumina (waste coal fly ash). These synthesis approaches are also based on the absence of a template or low-cost mixed organic templates (for instance, glycerol (GL), ethylene glycol (EG), and polyethylene glycol 200 (PEG)) or pyrrolidine-based mesoporogen (N-cetyl-N-methylpyrrolidinium) modifying the mordenite framework which can create unique properties. The framework properties and optical properties (indium-exchanged mordenite zeolite) have been discussed. Mordenite is generally used in alkylation, dewaxing, reforming, hydrocracking, catalysis, separation, and purification reactions because of its large pore size, strong acidity, and high thermal and chemical stability, although the applications are not limited for mordenite zeolite. Recently, several applications such as electrochemical detection, isomerization, carbonylation, hydrodeoxygenation, adsorption, biomass conversion, biological applications (antibacterial activity), photocatalysis, fuel cells and polymerization reactions using mordenite zeolite were explored which have been described in detail in this review.