电絮凝处理腐殖酸过程中阳极钝化影响因素分析  

Influence factors of anode passivation during humic acid electrocoagulation treatment

作　　者：田家宇 霍佳文 胡承志 赵凯[2] 马方凯[3] 邵军荣 孙境求 TIAN Jiayu;HUO Jiawen;HU Chengzhi;ZHAO Kai;MA Fangkai;SHAO Junrong;SUN Jingqiu(School of Civil and Transportation,Hebei University of Technology,Tianjin 300400,China;Key Laboratory of Drinking Water Science and Technology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China;Changjiang Survey,Planning,Design and Research Co.Ltd.,Wuhan 430010,China)

机构地区：[1]河北工业大学土木与交通学院,天津300400 [2]中国科学院生态环境研究中心环境水质学国家重点实验室,北京100085 [3]长江勘测规划设计研究有限责任公司,武汉430010

出　　处：《环境工程学报》2022年第6期1789-1796,共8页Chinese Journal of Environmental Engineering

基　　金：国家重点研发计划(2020YFD1100500)。

摘　　要：针对电絮凝(electrocoagulation,EC)处理腐殖酸(humic acid,HA)过程中电极易发生钝化,造成处理效能下降的问题,主要探究了阳极表面粗糙度、初始pH、初始HA浓度对于铝阳极钝化的影响,随后通过检测溶液中残留Al^(3+)浓度和阳极板表面形貌,进一步分析了HA浓度对于铝阳极钝化发展的影响机制。结果表明:铝阳极钝化程度与阳极板表面算数平均粗糙度(arithmetic mean roughness,Ra)呈负相关,随着Ra从2055 nm下降到270 nm,阳极板的电荷转移电阻(charge transfer resistor,Rct)从1174.0Ω·cm^(2)增大到1481.2Ω·cm^(2);当溶液初始pH从3提高到7时,极板的Rct从461.0Ω·cm^(2)增大到1120.2Ω·cm^(2),而当pH继续升高到9时,极板的Rct下降到169.5Ω·cm^(2);铝阳极钝化程度随溶液初始HA浓度呈现先减小后增大的规律。HA的质量浓度从0 mg·L^(-1)提高到20 mg·L^(-1)时,对应极板的Rct从1536.4Ω·cm^(2)减小到932.9Ω·cm^(2),HA的质量浓度进一步上升至200 mg·L^(-1)时,对应极板的Rct又从932.9Ω·cm^(2)增大到1403.2Ω·cm^(2)。本研究结果可为EC在实际应用中抑制阳极钝化提供参考。Aiming at the passivation problem of the anode during the electrocoagulation(EC) treatment of humic acid(HA) which can decrease the removal efficiency,the effects of surface roughness,initial pH,and initial HA concentration on the passivation degrees of aluminum anodes were investigated in this study.The passivation mechanism was further analyzed by detecting the concentration of residual Al^(3+) in the solution and the surface morphologies of the anodes.The results showed that the passivation degree of the aluminum anode was negatively correlated with the arithmetic mean roughness(Ra) of its surface.The charge transfer resistance(Rct) of the anode increased from 1 174.0 Ω·cm~2 to 1 481.2 Ω·cm~2 when Ra decreased from 2 055 nm to270 nm.In addition,when the initial pH of the solution increased from 3 to 7,Rct of the anode increased from461.0 Ω·cm~2 to 1 120.2 Ω·cm~2.And when the pH continued to rise to 9,Rct decreased to 169.5 Ω·cm~2.The passivation degree of the anode first decreased and then increased with the increase of the initial HA concentration.When the HA concentration increased from 0 mg·L^(-1) to 20 mg·L^(-1),Rct of the corresponding anode decreased from 1 536.4 Ω·cm~2 to 932.9 Ω·cm~2.And when the HA concentration further increased to200 mg·L^(-1),the corresponding Rct increased from 932.9 Ω·cm~2 to 1 403.2 Ω·cm~2.This study provides a theoretical and technical support for anode passivation mitigation in practical application of EC.

关 键 词：阳极钝化 电絮凝 腐殖酸 水处理 

分 类 号：X703.1[环境科学与工程—环境工程]