The escalating problem of nitrate pollution, coupled with the environmental burden of the Haber-Bosch process, has spurred intense interest in the electrocatalytic nitrate reduction reaction (eNO3RR) as a sustainable route for simultaneous wastewater treatment and ammonia production. However, the efficiency and selectivity of eNO3RR are hampered by the multi-step proton-coupled electron transfer process and the competing hydrogen evolution reaction. This review provides a comprehensive and critical overview of recent advances in understanding and designing catalysts for eNO3RR. We begin by elucidating the fundamental mechanisms and key reaction pathways, followed by a discussion on how critical parameters (e.g., electrolyte microenvironment, applied potential, reactor design) dictate performance. Further discussion of recent advances in catalysts, including single-metal catalysts, alloy catalysts, transition metal compounds, single-atom catalysts, carbon-based non-metal catalysts, and composite catalysts, highlights their significant roles in enhancing both the efficiency and selectivity. A distinctive feature of this review is its consistent critical assessment of catalysts through the dual lenses of practicality and sustainable development. Finally, we outline prevailing challenges and propose future research directions aimed at developing scalable and commercially viable electrocatalytic systems for green nitrogen management.

To reduce the environmental pollution caused by pathogens and radioactive substances carried by medical waste, and alleviate the shortage of non-renewable energy, this work proposes a novel overall process for hydrogen production from medical waste by plasma gasification coupled with ionic liquid-based CO2 capture. The validity of the model is verified by the experimental data. Based on the simulation results, the effects of medical waste types, different gasification agents and carbon conversion rate on the syngas compositions, H2/CO ratio, carbon conversion rate, higher heating value and exergy efficiency are explored. The results show that the rate of hydrogen production from surgical masks is more than twice that of the other two types of medical waste. Steam is the best gasification agent. At this time, the higher heating value of syngas is 26.72 MJ/kg and the exergy efficiency is 78.25%. A comprehensive analysis of the thermodynamic efficiency and technical economy of the overall process shows that the total exergy efficiency is 70.84%. The production cost is 2115.74 USD and the raw material consumption is 2.61 t/t H2. This study can provide a promising theoretical guidance for the resource treatment of medical waste. © 2023 The Institution of Chemical Engineers

This wok proposed the extraction distillation coupled pervaporation (ED+PV) technology process using two different solvents to separate isopropanol (IPA) and diisopropylether (DIPE) from DIPE/IPA/H2O tern-ary heterogeneous azeotropes in industrial wastewater from the synthesis of isopropanol in this study. Based on strict design specifications, simulation and sequential iteration methods are used for process design and optimization. Compared to the ethylene glycol (EG)-EG+H2O process and the 1,3-propanediol (PDO)-IPA+H2O process, the total annual cost (TAC) of the EG-IPA+H2O process decreased by 20.76% and 7.86% (PDO). Compared to the EG-EG+H2O process, the TAC of the PDO-IPA+H2O process reduced 14%, but the global warming potential (GWP) and human toxicity of the PDO-IPA+H2O process increased 11.3% and 4.07% respectively. Compared to the PDO-IPA+H2O process, the EG-IPA+H2O process saves 7.86% (TAC), 9.78% (GWP) and 9.85% (human toxicity). The ED+PV process with EG is superior to PDO in factors of TAC, energy consumption, human toxicity and environment. The EG-IPA+H2O process changed the separation order of the products of the multi-azeotropic system, reduced the cost and energy conservation of the system, and enhanced the environmental protection evaluation of the process, is the best process through life cycle assessment for analyzing the economy, energy conservation, environmen-tal assessment and human toxicity, designing cleaner products, controlling waste discharge, and promot-ing the chemical purification industry. This work provides a new process design and optimized separation ideas, will have a good guiding significance for the research and application separation of multi-azeotropic mixture with mixed solvents in organic wastewater from the cleaner chemical produc-tion, has been up to standard wastewater discharge process, and realized the development goal of carbon peak and carbon neutrality in the sustainable development of chemical clean industry. (c) 2022 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.

At present, the market demand for methyl acetate (MEOAC) is small and there is the problem of overcapacity. As an important organic solvent, n-butyl acetate (nBuOAC) is widely used in industry. It is very important to explore the efficient transesterification synthesis and separation process of nBuOAC. In this work, the schemes of reactive-extractive distillation (RED), side-line reactive extractive distillation (SLRED) and reactive distillationpervaporation (RDPV) were proposed for the transesterification of MEOAC and n-butanol (nBuOH) to synthesize nBuOAC and methanol (MEOH). Firstly, according to the relative volatility of MEOAC and MEOH azeotrope systems, and the interaction energy and radial distribution function (RDF) were calculated by molecular dynamics (MD) to complete the screening of extractants. Then the process design is completed based on reaction kinetics, and the established processes with optimal operating conditions were obtained by the multi-objective particle swarm optimization algorithm. Finally, the total annual cost (TAC) and gas emissions are used to assess the economic efficiency and environment performance of these processes and the optimal process was obtained. The calculation results show that among the three proposed processes, the RDPV process performs best economically and environmentally. The TAC of RDPV is 8.17% lower than that of RED and 6.46% lower than that of SLRED. Meanwhile, the TAC of SLRED is 1.83% lower than that of RED. The gas emissions of RDPV is 23.13% lower than that of RED and 23.51% lower than that of SLRED, and there is little difference between RED and SLRED process.

Octane and p-xylene are common components in crude gasoline,so their separation process is very important in petroleum industry.The azeotrope and near azeotrope are often separated by extractive distillation in indust

For the extraction distillation process, the choice of entrainer is very important. Usually, the boiling point of the entrainer is higher than that of any of the components to be separated, while the mechanism of separation of azeotropic system with intermediate-boiling-point solvent as entrainer is not common. Taking the azeotrope of n-heptane and isopentyl alcohol as an example, the intermediate-boiling-point solvent of butyl acetate was determined as the entrainer. The experimental data of vapor–liquid equilibrium for the two systems of n-heptane isoamyl alcohol and n-heptane butyl acetate were analyzed. After the thermodynamic consistency test, the binary interaction parameters of three models were obtained by correlating and regressing the experimental data. The possibility and mechanism of the extraction of azeotropic system by the intermediate-boiling-point solvent were analyzed from the aspects of σ-profile, interaction energy and charge density by the principle of quantum chemistry and molecular dynamics. The results showed that the tendency of hydrogen bond between the intermediate-boiling-point solvent and the azeotropic system was different: one component interacted with each other in the form of hydrogen bond, and the other had no hydrogen bond. The mechanism of the intermediate-boiling-point solvent as the entrainer to separate azeotropic system was verified in the extractive distillation process. © 2022 Elsevier Ltd

Exploring the process of cost-effective and efficient technology to separate ternary aqueous azeotropic systems has become essential research in chemistry and materials science. Traditional distillation technology and promising membrane technology occupy an irreplaceable position in wastewater treatment. However, single separation technology for the separation of azeotropic systems has disadvantages. To better meet the industrial practical needs of different azeotropic compositions in each process of rapeseed oil production, the separation performance and economic cost of single extractive distillation and an extractive distillation coupled pervaporation process for ternary azeotropic systems with different feed compositions were studied. Environmentally friendly and effective solvents were selected as extractants in the extractive distillation process from two aspects: selectivity and biological toxicity. Sequential iterative optimization algorithms were used to optimize the process with the ratio of water to the total amount of cyclohexane and isopropanol ranging from 1:9 to 9:1, considering cost as the evaluation index. The results showed that the cost of the processes increases significantly with increasing water content in the feed composition. Because the flux and selectivity of the membrane module were considerably affected by temperature when the water content was less than 0.4, the integrated process was more economical; otherwise, the extractive distillation process was more economical when the water content was greater than 0.4.

Present industrial development has a great demand for butyl acrylate, an important basic chemical. Efficient synthesis and separation processes are very important for the clean manufacturing of butyl acrylate. In this work, two processes for the preparation of butyl acrylate by reactive distillation coupled with azeotropic distillation (RD-AD) or pervaporation (RD-PV) were proposed. By changing the ratio of reactants, the economic performance of the two processes under different specifications of butyl acrylate was analyzed, and the environmental impact of the two processes in the production process were analyzed. First, the process design using different purity specifications was completed focusing on the reaction kinetics. Then, based on the sequential iterative algorithm, process optimization was carried out with the minimum total annual cost (TAC) as the objective function, and the process with optimal operating conditions was obtained. Finally, TAC and the global warming potential (GWP), acidification potential (AP), abiotic depletion potential (ADP) and human toxic potential (HTP) were used to assess the economic and environmental performance of the proposed processes. The results showed that the RD AD process had better economic performance, whereas the RD-PV process had better environmental performance. According to the results, the parameters that influenced the TAC for products with different purities were obtained. The TAC of the RD-AD process was 41.39% lower than that of the RD-PV process, and GWP, AP, and ADP of the RD-PV process were respectively 12.67%, 13.68%, and 13.07% lower than those of the RD-AD process.