| Electrochemical preparation technology is an efficient and environmentally friendly synthesis method that has gradually emerged as an important avenue for reducing energy consumption,minimizing pollution,and improving product quality in the synthesis of organic chemicals.With the application and development of renewable energy sources such as wind energy and solar energy,organic electrosynthesis technology is expected to be coupled with renewable energy to improve the consumption level of new energy and become a new direction for the development of green chemical industry under the"dual carbon"goals importantly.However,current researches on organic electrosynthesis focus on basic researches of synthetic methodology and product diversity,while paying less attention to engineering application research,which makes organic electrosynthesis technology unable to become a conventional method for chemical synthesis in industry.Only through the comprehensive breakthroughs in the applied fundamental problems such as the organic electrochemical reaction mechanism,the creation of key electrode materials,the design of efficient electrochemical reactors,and the development of economically reliable processes,can the industrialization of organic electrochemical synthesis be successfully achieved.Therefore,this paper selected dimethyl sebacate（DS）and N-acetyl-L-cysteine（NAC）,which have commercial prospects,as the target products of the anodic oxidation and cathodic reduction,respectively.Starting from the necessary considerations for achieving engineering applications including electrochemical reaction mechanism,electrode material screening and preparation,electrochemical reactor design and synthesis process development,we explore the common technology of organic electrochemical redox to achieve efficient and precise synthesis of target organic chemicals,aiming to form a demonstration effect and provide the basis for energy conservation,emission reduction,and technological upgrading of traditional organic synthesis industries.The main works of this paper are as follows.（1）It is demonstrated that the electrochemical method is a promising process for synthesizing DS from petrochemical raw material monomethyl adipate.We evaluated four commercial anode materials through theoretical calculations and experiments,confirming that Pt electrode exhibits the best oxidative decarboxylation coupling performance.This is attributed to the strong electronic interaction between the surface atoms and the adsorbed MA,which promotes the decarboxylation reaction.Through the single-factor experiments and response surface analysis,the influence of current density,water content,MA concentration,and neutralization degree on the electrolytic synthesis yield of DS was explored.The order of influence is water content>current density>MA concentration>neutralization degree.A quadratic polynomial mathematical model for the MA decarboxylation coupling reaction was established,and the optimal process parameters for DS electrolytic synthesis were obtained.（2）A platinum-coated titanium anode with the hydrophobic micro-nano hierarchical structure was prepared to achieve efficient synthesis of DS in a methanol-water mixture.Using Pt/Ti and mn-Pt/Ti as anodes,the electrolysis mechanism on hydrophilic and hydrophobic electrode surfaces in aqueous organic electrolytes was explored.The traditional hydrophilic flat Pt/Ti electrode tends to preferentially adsorb water molecules,leading to oxygen evolution.The resulting bubbles grow and accumulate on the electrode surface,generating micro-convection that hinders ion transport and blocks active sites.In contrast,the hydrophobic micro-nano hierarchical structure of mn-Pt/Ti suppresses water molecule adsorption on the electrode surface,which inhibits bubble accumulation,enhances the adsorption of monomethyl adipate,and promotes continuous electron transfer between the electrode and organics.Furthermore,mn-Pt/Ti electrode surfaces with different hydrophobicity were designed and prepared,and it was demonstrated that the degree of electrode surface hydrophobicity is positively correlated with the Faradaic efficiency of electrolysis.In the electrolysis of DS,the Faradaic efficiency of over 55%was maintained after 10electrolysis cycles at a high current density of 100 m A cm-2.（3）A micro-spacing flow electrochemical reaction system has been successfully developed for the electrolytic decarboxylation coupling synthesis of DS.Emphasis should be placed on its practicality and modular assembly to ensure high efficiency and reliability.The system adopts the design concept of a parallel plate electrochemical reactor,selects the optimal flow channel parameters through evaluation,and maximizes the overall performance of the device.The flow and mass transfer characteristics of the reactor were deeply studied,and their effects on the electrosynthesis efficiency of DS were explored.Experimental results showed that the S-shaped flow field micro-spacing flow reactor with a smaller thickness of 0.2 mm exhibits excellent mass transfer coefficient and Reynolds number,giving it significant advantages in the electrosynthesis of DS.Compared with traditional stirred batch electrochemical reactors,the micro-spacing flow reactor can reduce energy consumption by up to 91.3%.（4）An alternative green and efficient process for the preparation of NAC was proposed based on organic synthesis,electrochemical reduction,and electrodialysis desalination techniques.Electrochemical reduction is a key step in this process,therefore we delved into the electrode process kinetics of disulfide bond cleavage.Compared to traditional methods,the strategy of acylation followed by electrolysis,coupled with the carbon cathode and electrodialysis desalination technology,addresses a range of issues faced by traditional processes,significantly reduces waste emissions,and achieves an upgrade and transformation of the process.Utilize an integrated flow parallel plate electrochemical reactor to achieve scale up of the process,and reasonable technical and economic analysis was conducted based on the scale-up experiments. |
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