BDD电极电催化降解苯酚废水的研究  

ELECTROCHEMICAL DEGRADATION OF PHENOL WASTEWATER AT BORON-DOPED DIAMOND ELECTRODES

作　　者：吕江维[1,2] 冯玉杰[1] 曲有鹏[3] 刘峻峰[1] 崔福义[1] 

机构地区：[1]哈尔滨工业大学城市水资源与水环境国家重点实验室,150090 [2]哈尔滨商业大学药学院,150076 [3]哈尔滨工业大学生命科学与技术学院,黑龙江哈尔滨150080

出　　处：《水处理技术》2013年第10期53-58,共6页Technology of Water Treatment

基　　金：国家自然科学基金项目(51308171;51209061);中国博士后科学基金项目(2011M500671);哈尔滨商业大学博士科研启动项目(13DL026)

摘　　要：采用直流等离子体化学气相沉积方法制备了硼掺杂金刚石(BDD)薄膜电极。以苯酚为目标污染物,研究了苯酚废水在电极上的电化学降解规律及降解历程。结果表明,不同浓度的苯酚在电极上均能够完全矿化成CO2。高浓度条件下,苯酚先转化成中间产物,然后中间产物再氧化成CO2;低浓度条件下,苯酚氧化反应迅速,直接矿化成CO2。提高电流密度能够加速苯酚的降解,但会导致电流效率下降。苯酚的降解历程为对位首先受到·OH自由基的攻击,生成对苯二酚,再开环形成顺、反丁烯二酸与乙酸,然后顺、反丁烯二酸在阴极还原为丁二酸,丁二酸氧化脱羧形成丙二酸、乙酸、草酸或甲酸,最终氧化成CO2。Boron-doped diamond （BDD） electrodes were deposited on Si substrates by direct current plasma chemical vapor deposition （DC-PCVD）system. The results showed that phenolwith different initial concentrations was completely mineralized to CO2 at BDD electrode, favoring electrochemical combustion. Phenol with high initial concentration was initially converted to intermediates and then finally mineralized to CO2. Phenol with low initial concentration was rapidly mineralized to CO2. Phenol degradation at high current density resulted in high removal rate for phenol and total organic carbon （TOC） but low minerolization current efficiency （MCE）, which arose from side reaction of oxygen evolution. Phenol degradation pathway was analyzed by high performance liquid chromatography （HPLC）. It was found that the para site of phenol was attacked by ~ OH radical first, then formed hydroquinone and the ring was broken into maleic acid, fumaric acid and acetic acid, Maleic acid and fumaric acid were reduced into succinic acid at cathode which were further oxidized into malonic acid, acetic acid or formic acid. These small organic acids were finally oxidized into CO2.

关 键 词：硼掺杂金刚石（BDD） 电催化 苯酚废水 化学气相沉积 羟基自由基 

分 类 号：X703.1[环境科学与工程—环境工程] TQ031.7[化学工程]