高压脉冲气液相放电对双酚A降解的研究

Degradation of Bisphenol A in Aqueous Solution by High Voltage Pulsed Gas-liquid Discharge

双酚A(Bisphenol A,BPA)因较大的使用量导致其在全球水体、沉积物、土壤中广泛分布,由于其分子结构稳定和一定的毒性及内分泌干扰性受到了中外极大关注,迫切需要有效的方法进行降解。运用高压脉冲放电等离子体技术研究对BPA溶液的降解效果,搭建反应器并研究了电场参数对降解去除率的影响,并使用最优电场参数结合环境因子变量研究去除效果。结果表明:电压高于30 kV、极间距1.5~2.5 cm有利于提高电场强度提高BPA去除效率;而提高放电频率可增加单位时长内的电场强度从而在反应前期BPA降解速率更高。溶液中BPA初始浓度和电解质的增加并不影响反应的进行;BPA放电降解较优的pH在7.0~9.0,而溶液初始pH较低和较高时都将降低反应速率。可见在适当的理化条件下,高压脉冲放电对BPA有较好的去除效果。

Worldwide usage of Bisphenol A(BPA)led to its ubiquitous distribution in water,sediment and soil.Moreover,BPA has been identified as an environmental endocrine disruptor for its estrogenic and genotoxic activity.Thus,BPA contamination in the environment is an increasingly worldwide concern,and methods to efficiently remove BPA from the environment are urgently recommended.High-voltage pulsed gas-liquid discharge was used to treat the BPA in aqueous solutions with the pulsed electric field.High voltage pulsed discharge plasma technology was established and subsequently applied for the degradation of BPA,and the effects of various pulsed electric field parameters on the degradation of BPA in the solution were investigated.Results obtained indicated the following:removal efficiency of BPA solution is better when the peak voltage above 30 kV and when the electrode gap distance is between 1.5 cm to 2.5 cm are beneficial to the enhancement of electric field intensity.The contribution rate of discharge frequency to the degradation of BPA decreases with the increase of discharge reaction time.The degradation efficiency of BPA was slightly enhanced in higher initial concentration compared to lower concentration.Then the initial solution pH had positive effects on the degradation efficiency of BPA.The optimum pH range for BPA degradation by high voltage discharge is neutral or weak alkaline conditions,which the range in pH value from 7.0 to 9.0.In the strong acid or alkali solution circumstance,the BPA degradation reaction rate will decrease.