Experimental Study On The Treatment Of Tc-hcl In Pharmaceutical Wastewater By Advanced Oxidation Of Persulfate

Pharmaceutical wastewater is difficult to degrade and harmful to the environment.Its degradation treatment is a hot and difficult topic in the field of environmental research.According to the type of medicines,it can be divided into antibiotic wastewater,chemical production wastewater and traditional Chinese medicine production wastewater.Among them,antibiotics account for the largest proportion.In antibiotic wastewater,tetracycline antibiotics have been widely used,and the wastewater not only seriously damages the environment,but also leads to bacteria resistance.Therefore,attention should be paid to the treatment of such pollutants,and efficient and effective treatment methods are urgently required.The advanced oxidation method has the advantages of fast reaction and small secondary pollution,and has been mostly used in the treatment of organic pollutants in recent years.Based on the advanced oxidation method of persulfate and the activation effect of transition metals on persulfates,the transition metal-carbon matrix composites were first designed and prepared using microwave tubular furnaces,and then the activation properties and degradation effects in heterogeneous systems were explored by using tetracycline hydrochloride as the target pollutants,and the variable optimization and degradation mechanism analysis were carried out by univariate experiments.The conclusions are as follows(1)Iron,manganese and bimetals were selected to be the active metals supported on carbon-based materials,and the composite materials were prepared in a microwave tube furnace by immersion and pyrolysis methods,and the degradation balance experiment and characterization analysis were carried out to find the best preparation conditions.Among them,the loading ratio affected the binding of elements in the system and the degree of catalyst defects,and the temperature affected its pore structure and the abundance of functional groups.After two aspects of exploration,it was found that when the supported metal was iron with loading ratio of 1%,the metal manganese with loading ratio of 5% and bimetallic catalysis with loading ratio of 5:1 at pyrolysis temperature of 500 °C,the degradation performance was the best.All could meet emission standards.(2)The catalyst under the optimal preparation conditions was selected for single-factor experiments to explore the influence of different experimental variables on the degradation effect.The optimal dosage was 50 mg,and the mass ratio of catalyst to sodium persulfate was 30.At this dosage,the degradation ratio of 1-Fe-500 was 98% at p H 3 and 12 h;the degradation ratio of 5-Mn-500 was 99% at p H 13 and 12 h.The degradation ratio of the bimetallic composite reached 95% in 1 h under neutral conditions.In this paper,using the activation effect of transition metals on persulfate,the advanced oxidation method was used to degrade tetracycline hydrochloride.The degradation process was fitted with pseudo-second-order kinetics,and the main free radicals in the system were obtained by controlling variables,and the main degradation route was deduced through intermediates.This study is expected to provide systematic theoretical basis and technical support for removing such drugs in practice.