Research On Electrochemical Detection Of Bisphenol S In Water And Its Magnetic Biochar Adsorption Enrichment-Microwave Degradation Technology

Bisphenol S?BPS?,as a substitute for bisphenol A?BPA?,is widely used and exists in our living environment.At present,BPS has been detected in rivers,sludge,sediments,indoor dust,foodstuffs,consumer products and human urine.Although the effects of exposure to BPS on human body are not clear,some studies indicate that BPS may have potential health hazards of the same magnitude as BPA.Therefore,the detection and degradation of BPS have become an important issue in the field of environmental science.Taking BPS as the target pollutant,this paper could be mainly divided into two sections:On the one hand,MoS₂ was stratified by protein stratification technology to improve performance of MoS₂/PANI composite,then BPS was electrochemically detected with MoS₂/PANI composite modified glassy carbon electrode.On the other hand,Fe₃O₄/BC composite was prepared by chemical coprecipitation method.The optimum adsorption and desorption conditions were sought,then BPS was degraded by microwave integrated advanced oxidation process and the adsorbent material was regenerated at the same time.MoS₂/PANI composite modified glassy carbon electrode was used for detection of BPS with differential pulse voltammetry from 1 to 100?mol·L^-1.The peak current values?I_p?and concentrations?C?of BPS were described as:in the low concentrations range(1-10?mol·L^-1)the linear relationship can be denoted as I_p??A?=1.31952+0.06967C(?mol·L^-1)?R²=0.9938?,while in the high concentrations range(10-100?mol·L^-1)it can be denoted as I_P??A?=1.56739C(?mol·L^-1)+0.03943?R²=0.9967?.The BET characterization of Fe₃O₄/BC composite shows that its large specific surface area and mesoporous structure are very conducive to the adsorption of BPS;XRD and FTIR further prove that Fe₃O₄ and BC were loaded with each other;TGA shows that the composite has excellent thermal stability.Fe₃O₄/BC composite was used for adsorption of BPS and the results showed that it had a high adsorption capacity for BPS and good magnetism;The kinetics of adsorption conformed to the second-order kinetics model and isotherm of adsorption accorded with Freundlich adsorption isotherm model;Further study proved that the adsorption reaction is spontaneous and endothermic,and the adsorption belongs to physical adsorption;The maximum adsorption capacity reached 62.46 mg·g^-1 in 288 K.Microwave treatment of Fe₃O₄/BC composite with 20 mg·L^-1 BPS saturated was carried out.The results showed that the degradation rate of BPS was 83%when the microwave power was 70 W,microwave time was 2 min and the concentration of H₂O₂ was 0.3 mol·L^-1.After five rounds of cyclic experiments,the removal rate of BPS decreased slightly,but it was still as high as 75%.The results of mechanism study showed that there was significant synergistic effect between hydrogen peroxide and microwave,hydroxyl radicals?·OH?and holes?h⁺?were the main active species in BPS degradation.