钴、硫共掺杂荞麦皮生物炭活化PMS高效降解碘帕醇  

Efficient activation of peroxymonosulfate by Co,S co-doped buckwheat husk biochar for iopamidol degradation

作　　者：宋俊其 魏红[1] 潘峰[1] 滕锐杰 高美娟 钮金芬[2] SONG Junqi;WEI Hong;PAN Feng;TENG Ruijie;GAO Meijuan;NIU Jinfen(State Key Laboratory of Eco-Hydraulics in Northwest Arid Region,Xi’an University of Technology,Xi’an 710048;Department of Applied Chemistry,Xi'an University of Technology,Xi'an 710048)

机构地区：[1]西安理工大学,西北旱区生态水利国家重点实验室,西安710048 [2]西安理工大学,应用化学系,西安710048

出　　处：《环境科学学报》2024年第7期69-82,共14页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.51979223);陕西省自然科学基金(No.2022JM-093)。

摘　　要：选择荞麦皮为前驱体,二甲基亚砜和Co(NO_(3))_(2)·6H_(2)O分别为S和Co源,经水热、热解制备Co S-BBC催化剂.利用SEM、XRD、Raman、FTIR等方法进行表征,考察其催化PMS降解碘帕醇(Iopamidol,IPM)的性能.通过自由基淬灭实验、电子顺磁共振(EPR)、电化学测试和反应前后Co S-BBC的表征探究其催化PMS的机理.采用液相色谱-质谱仪(LC-MS)分析IPM的中间产物,推测其降解途径,并利用生态结构活性关系模型(ECOSAR)预测其生态毒性变化.结果表明,随热解温度升高(600~800℃),Co S-BBC-800显示较高的缺陷程度和较大比表面积(511.02m^(2)·g^(-1),0.2273 cm^(3)·g^(-1)),且表现出优异的催化性能.Co S-BBC-800投加量0.02 g·L^(-1),PMS浓度1.0 mmol·L^(-1),初始p H=6.5,10 mg·L^(-1)的IPM在8min完全降解(k_(obs)=0.427 min^(-1)),Co^(2+)的浸出浓度仅为0.36 mg·L^(-1).电化学实验(CV、EIS、LSV和i-t)表明S的引入促进了电子转移和Co(Ⅲ)/Co(Ⅱ)的氧化还原循环,增强PMS活化产生更多SO_(4)^(·-)、·OH和^(1)O_(2).IPM降解过程生成11种中间产物,一些中间体具有一定的生态风险.Co S-BBC-800在较宽p H(5.0~9.0)保持较好的催化性能.5次循环后对IPM的降解率为47.4%.研究结果表明Co、S负载可有效提高荞麦皮的高价值资源化利用.This study reports the synthesis of cobalt sulfide loaded on biochar derived from buckwheat husk (Co S-BBC) using dimethyl sulfoxide and Co(NO_(3))_(2)·6H_(2)O as S and Co sources,respectively,through hydrothermal and pyrolysis processes.Then Co S-BBC was characterized by SEM,XRD,Raman and FTIR analysis.Its catalytic activation on PMS degrading iopamidol was further investigated.Free radical quenching experiment,electron paramagnetic resonance (EPR),electrochemical test and characterization of Co S-BBC were conducted to explore the reaction mechanism.The degradation intermediates of IPM were identified by liquid chromatography-mass spectrometry,and their respective eco-toxicity were predicted by the Ecological Structure-Activity Relationship Model (ECOSAR).The results indicated that the defect degree of Co S-BBC enhanced with increasing pyrolysis temperature in the range of 600~800℃,with Co S-BBC-800 exhibiting the highest defect degree,largest specific surface area (511.02m^(2)·g^(-1),0.2273 cm^(3)·g^(-1)),and excellent catalytic activity.IPM (10 mg·L^(-1)) can be completely degraded in 8 min (k_(obs)=0.427 min^(-1)) under the optimum condition (Co S-BBC-800 dosage of 0.02 g·L^(-1),PMS concentration of 1.0 mmol·L^(-1) and an initial p H=6.5),with the Co^(2+)leaching concentration only0.36 mg·L^(-1).Electrochemical analysis (CV,EIS,LSV and i-t) results showed that the introduction of S promoted electron transfer and the redox cycle of Co(Ⅲ)/Co(Ⅱ),therefore enhanced the activation of PMS to produce more SO_(4)^(·-),·OH and ^(1)O_(2).Eleven intermediates were identified,however,some of which posed certain ecological risks.Co S-BBC-800 exhibited stable catalytic performance across a wide p H (5.0~9.0),but showed a decrease after 5 cycles with IPM degradation rate dropping to 47.4%.This study demonstrated that Co and S loading can effectively improve the resource utilization and valuation of buckwheat husk.

关 键 词：荞麦皮生物炭 钴、硫掺杂 过一硫酸盐 碘帕醇 催化氧化 

分 类 号：X131[环境科学与工程—环境科学]