Solar-Driven Hyperthermal Electrochemical Engineering For Degradation Of Phenol In Wastewater

The development and utilization of clean renewable energy represented by solar energy is considered as the effective measure to cope with climate change and promote the transformation of energy structure under the background of“carbon peaking and carbon neutrality goals”.The comprehensive utilization of solar spectrum has become a common direction for research scholars.Water pollution has always been one of the ordinary problems faced by the international community,among which phenol,as an important chemical raw material and by-product during the industrial production,is highly polluting,toxic and difficult to degrade,posing a great threat to both human and environment.In this paper,we propose the theory and technology of solar-driven hyperthermal electrochemical engineering for the treatment of phenol wastewater with the context of organic wastewater treatment and solar energy utilization.The effects of different experimental parameters（reaction temperature,current density,filling medium,electric field strength,etc.）on the degradation of phenol were investigated systematically.The study is intended to provide a new technical route for future organic wastewater treatment processes.The main research work was summaried as follows:1.Theoretical analysis of organic wastewater treatment process driven by solar was carried and a model of wastewater degradation was established.The results of thermodynamic calculations and cyclic voltammetric tests revealed that high temperature can effectively activate phenol molecules,reduce the electrochemical electrolysis potential and promote the oxidative degradation reaction.2.An intermittent reaction system driven by solar was established to investigate the optimal reaction conditions for the degradation of phenol wastewater.The results clarified that high-temperature environment has a significant promotion effect on the oxidative degradation of phenol.The degradation rate of phenol reached 98%and the removal rate of COD reached93%after treating for 120 min under the optimal conditions of 150℃,current density 50 m A cm^-2,concentration of Na₂SO₄ 15 g L^-1 and maintaining the original p H of the solution.In the coupled model of hyperthermia-electrochemistry,the degradation of phenol conformed to the first-order kinetic equation.The degradation pathway of phenol in high temperature environment was significantly shortened based on the comprehensive analysis of UV spectrum,IR spectrum and liquid chromatography.3.The hyperthermal electrochemical continuous wastewater treatment system driven by solar was constructed with the support of experimental data from the intermittent system.The degradation rate of phenol was 37%and COD removal rate was 36%in the electric field induced pyrolysis system.The treatment effect was not up to the ideal level.While in the thermal field induced electrolysis system,the phenol wastewater treatment effect reached the best when alumina was chosen as the filling medium.The degradation rate phenol was 96%and COD removal rate was 93%.A simulation model of mechanized power generation coupled with wastewater treatment process was established combining the continuous process of wastewater treatment with solar thermal power generation system.