The CO2 reforming of methane to syngas was examined over five different supported catalysts. In this study, 5% Ni was used as the active metal part of the catalyst. To better comprehend the impact of the supports on the catalytic properties, 5% Ni-based catalysts were characterized using nitrogen adsorption–desorption isotherms, XRD, H2-TPR, CO2-TPD, TGA, TPO, FTIR, and Raman. The results showed that the catalyst support with the highest surface area provided the best catalytic activity. The acquired CH4 and CO2 conversions at 700 °C were 58.2% and 67.6%, respectively, with a hydrogen/carbon ratio of 0.85. The TGA investigation of the high-surface-area sample produced a minimum carbon deposition of 11.2 wt.%, and in the CO2-TPD investigation, the high-surface-area sample exhibited the absence of a peak in the strong-basic-sites zone. The formation of NiAl2O4 spinel, moderate basicity, and the high surface area explained the outperformance of the high-surface-area catalyst sample.
Dimethyl carbonate (DMC) is an eco-friendly and sustainable compound with widespread industrial applications. Various extensive routes have been exploited in the chemical industry to produce DMC. However, these routes have several environmental and energy drawbacks. In this study, a promising novel industrial scheme for the synthesis of DMC via the oxidative carbonylation of vaporized methanol with dimethyl oxalate (DMO) as a byproduct is investigated. A methanol conversion of 81.86% and a DMC selectivity of 83.47% were achieved using an isothermal fixed-bed reactor at 130 °C. The DMC is withdrawn at a purity of >99 mol% via pressure-swing azeotropic distillations. Heat integration was performed to optimize energy consumption, reducing the energy requirements by 28%. An economic evaluation was performed for estimating the profitability via cash-flow diagrams, predicting a payback period of 3.7 years. The proposed green process exhibits several benefits, including high profitability and being environmentally friendly. It also eliminates the use or production of hazardous materials, and it enhances safety characteristics.
Biodiesel is considered valuable to reduce dependency on petrofuels. This work aimed to synthesize biodiesel from Silybum marianum using synthesized ZnO nanoparticles as a catalyst. The synthesized ZnO nanoparticles were examined by scanning electron microscopy and X-ray diffraction for confirmation. The synthesized biodiesel was confirmed by ASTM D-6751, H and C-NMR, GC-MS, and FT-IR spectroscopy. The optimum biodiesel yield of 91% was obtained with an oil-to-methanol ratio of 1:24, 15 mg of catalyst concentration, 60 °C temperature, and 45 min of reaction time. Fuel properties were determined according to the ASTM-defined methods and found within the defined limits of ASTM D-6751. 1H-NMR and 13C-NMR showed characteristic peaks at 3.667 ppm, 2.000–2.060 ppm, 0.858–0.918 ppm, 5.288–5.407 ppm, 24.93–34.22 ppm, 172.71, 173.12, 130.16 ppm, and 128.14 ppm, respectively, which confirm biodiesel synthesis. The FAMEs composition of biodiesel was determined by GC-MS, which recognized 19 peaks for different types of FAMEs. FT-IR spectroscopy showed two main peaks, first in the range of 1725–1750 cm−1 and second in the range of 1000–1300 cm−1, which confirmed that the transesterification process had completed successfully. The physicochemical characteristics of Silybum marianum confirm that it is a suitable source to produce biodiesel on an industrial scale.
In this research work, an attempt has been made to address the heat and power integration opportunities for the process of the chlorination of benzene. This process produces a mixture of chlorobenzenes. To increase the production of the dichlorobenzene portion, the ratio of chlorine to benzene is typically 2:1. A process simulation model is designed using Aspen Plus for the production of 70,000 tons/year of dichlorobenzene via the reaction of liquid benzene with gaseous chlorine. Energy analysis is performed for the effective utilization of the utilities by networking the heat exchangers. This modification reduced the process heating and cooling requirements by 56.7% and 12.7%, respectively, and a reduction by 35.4% in the operating costs is achieved, while the annualized fixed cost increased by 9.6%; these changes resulted in savings in the total annual costs of about 10.9%.