A Study On The Enhanced Degradation Of Printing & Dyeing Wastewater By Three-dimensional Electrolysis

At present,China is facing more and more environmental safety problems.The large amount of waste generated in industrial production has caused serious threats to our environment and human safety.As a typical industrial wastewater,printing dyeing wastewater has the characteristics of large amount of production,high chemical stability and difficult to degrade,which seriously threatens the natural environment and human body safety.Therefore,efficient treatment of dyeing wastewater is of great significance for wastewater treatment.In this paper,Rhodamine B is the main target pollutant,and the simulated dyeing wastewater is degraded by three-dimensional electrolysis.The main research contents are as follows:The degradation effects of three pairs of electrodes systems and three electrolytes on rhodamine B were studied.The research shows that under the conditions of catalytic?Ti/Ru-Ir-SnO₂?-titanium electrode pair and sodium chloride as electrolyte the removal rate of rhodamine B is the best.Through SEM-EDS characterization and electrochemical performance testing of the plates,the catalytic and corrosion resistance of the catalytic plates is optimal.Therefore,it was determined that the catalytic plate was used as the anode,the titanium plate was used as the cathode,and sodium chloride was used as the electrolyte to construct a three-dimensional electrolytic reactor.GAC-Mn,GAC-Mn/Sn,GAC-Mn/Sb type particles and?-Al₂O₃-Mn,?-Al₂O₃-Mn/Sn,?-Al₂O₃-Mn/Sb type particles were prepared and characterized by SEM,EDS and XRD.By comparing the degradation effects of Rhodamine B under different particle conditions,the GAC-Mn/Sn particles were judged as the best particle electrode.The best experimental conditions for the degradation of Rhodamine B by three-dimensional electrolysis under the particle condition were determined by response surface methodology were:the initial concentration was 300 mg/L,the applied voltage was 8.73 V,the particle dosage was 6.49 g,and the electrolyte concentration was 0.74 g/L.Under this condition,the removal rate of Rhodamine B is96.45%,the treatment energy consumption is 48 kW·h,and the conversion treatment cost is 33.6 yuan/kg.The experiments on the GAC-Mn/Sn were carried out several times to verify the reusability and stability of the particle electrode.The degradation effects of three-dimensional electrolysis on three different structural dyes:methyl orange?MO?,methylene blue?MB?and methyl violet?MV?,were studied.The results show that the three-dimensional electrolysis method has good degradation effects on the three dyes.The dynamic three-dimensional electrolysis combined with aerobic biochemical treatment device was designed by the static experiment with the best electrolysis time of 30 min and the best biochemical treatment time of 12 h.After combined treatment,the removal rate of rhodamine B and COD degradation rate reached 98.2%and 99.1%,respectively.The water samples of different electrolysis time were analyzed by UV-vis and UPLC-MS,and the degradation mechanism of rhodamine B was preliminarily discussed,the treated Rhodamine B product is mainly phthalic acid and benzoic acid.And the reaction process of removing rhodamine B by three-dimensional electrolysis fitted well with the first-order reaction kinetic model.