电晕放电等离子体对水中邻苯二甲酸二甲酯的降解

Degradation of aqueous dimethyl phthalate by corona discharge plasma

采用电晕放电等离子体降解水中的邻苯二甲酸二甲酯,研究了放电输出功率、溶液初始浓度、空气流量、初始p H、Fe2+和羟基自由基清除剂对邻苯二甲酸二甲酯去除效率的影响,并对其降解动力学进行了初步模拟。结果表明,电晕放电等离子体对水中邻苯二甲酸二甲酯有较好的去除效果。在放电功率45 W、初始浓度50 mg·L^(-1)、空气流速2 L·h-1、初始p H 6.31、初始电导率4.05μS·cm-1的条件下,反应30 min,邻苯二甲酸二甲酯的去除率可达到95%。酸性条件下有利于邻苯二甲酸二甲酯的降解。添加Fe2+,在反应初期可显著提高邻苯二甲酸二甲酯的降解率。羟基自由基清除剂的加入在一定程度上抑制了邻苯二甲酸二甲酯的降解。电晕放电等离子体降解邻苯二甲酸二甲酯的过程基本符合一级反应动力学。

Corona discharge plasma was utilized to degrade aqueous dimethyl phthalate. The effects of the power intensity,initial solution concentration,airflow rate,initial p H,and Fe2 ＋and hydroxyl free-radical scavenger concentration on the efficiency of dimethyl phthalate removal were studied. The kinetics of dimethyl phthalate degradation was preliminary simulated. Higher efficiency for the removal of dimethyl phthalate from an aqueous medium was achieved. After 30 min,the efficiency of dimethyl phthalate degradation reached 95% using a power intensity 45 W,the initial concentration of 50 mg·L^（-1）,an airflow rate of 2 L·h- 1,the initial p H of 6. 31,and the initial conductivity of 4. 05 μS·cm- 1. Acidic conditions were beneficial for dimethyl phthalate degradation. In the initial stages of the reaction,the efficiency of dimethyl phthalate degradation was improved by the presence of Fe2 ＋,but addition of a hydroxyl free-radical scavenger could decrease the efficiency of dimethyl phthalate degradation. The degradation of dimethyl phthalate by corona discharge plasma followed first-order reaction kinetics.