Recent progress in synergistic electrocatalysis for generation of valuable products based on water cycle

Given the grim situation of global warming and energy crisis,replacing traditional energy conversions based on carbon cycle with water cycle is a sustainable development trend.The synergistic electrocatalysis for value-added chemical production through oxygen species(O_(ads):OH^(*),O^(*),and OOH^(*))and the active hydrogen species(H_(ads))derived from water splitting powered by“green”electricity from renewable energy resource(wind,solar,etc.)is a promising manner,because of its reduced energy consumption and emission and high Faradaic efficiency.The study and summarization of catalytic mechanism of synergistic electrocatalysis are particularly significant,but are rarely involved.In this review,recent progress of various synergistic electrocatalysis systems for generating valuable products based on water cycle is systematically summarized.Importantly,the catalytic mechanism of synergistic electrocatalysis and the positive effect of O_(ads) and H_(ads) species produced by water splitting during the synergistic electrocatalytsis are detailedly elucidated.Furthermore,the regulation of water-derived O_(ads) and H_(ads) species for achieving efficient matchability of synergistic electrocatalysis is emphatically discussed.Finally,we propose the limitations and future goals of this synergistic system based on water cycle.This review is guidance for design of synergistic electrocatalysis architectures for producing valuable substances based on water cycle.

Glycerol waste to value added products and its potential applications

The rapid industrial and economic development runs on fossil fuel and other energy sources.Limited oil reserves,environmental issues,and high transportation costs lead towards carbon unbiased renewable and sustainable fuel.Compared to other carbon-based fuels,biodiesel is attracted worldwide as a biofuel for the reduction of global dependence on fossil fuels and the greenhouse effect.During biodiesel production,approximately 10%of glycerol is formed in the transesterification process in a biodiesel plant.The ditching of crude glycerol is important as it contains salt,free fatty acids,and methanol that cause contamination of soil and creates environmental challenges for researchers.However,the excessive cost of crude glycerol refining and market capacity encourage the biodiesel industries for developing a new idea for utilising and produced extra sources of income and treat biodiesel waste.This review focuses on the significance of crude glycerol in the value-added utilisation and conversion to bioethanol by a fermentation process and describes the opportunities of glycerol in various applications.

Increasing significance of advanced physical/chemical processes in the development and application of sustainable wastewater treatment systems

The awareness of the problem of the scarcity of water of high quality has strongly changed the approach of wastewater treatment.Currently,there is an increasing need for the beneficial reuse of treated wastewater and to recover valuable products and energy from the wastewater.Because microbiological treatment methods are,only to a limited part,able to satisfy these needs,the role and significance of physical/chemical processes in wastewater treatment are gaining more and more interest.The specific future role and aim of the various physical/chemical treatment processes can be categorized in five groups:improvement of the performance of microbiological treatment processes,achievement of the high quality required for reuse of the effluent,recovery of valuable components and energy from the wastewater for beneficial reuse,desalination of brackish water and seawater,and treatment of concentrated liquid or solid waste residues produced in a wastewater treatment process.Development of more environmentally sustainable wastewater treatment chains in which physical/chemical processes play a crucial role,also requires application of process control and modeling strategies.This is briefly introduced by the elaboration of treatment scenarios for three specific wastewaters.

A radical addition and cyclization relay promoted by Mn(OAc)_(3)·2 H_(2)O:Synthesis of 1,2-oxaphospholoindoles and mechanistic study

Novel and efficient Mn(OAc)_(3)·2 H_(2)O promoted radical addition-[4+1]cyclization relay of 3-indolymethanols and phosphites was disclosed,which afforded 1,2-oxaphospholoindole derivatives in moderate to good yields.Based on the experimental and computational studies,a mechanism involving radical addition and intramolecular cyclization cascade was proposed.