Yang Xian-Li, Bai Min-Dong, Han Feng
Key Laboratory of Strong Electric-Field Ionization Discharge of Liaoning Province, Institute of Environmental Engineering, Dalian Maritime University, Dalian 116026, China.
Huan Jing Ke Xue. 2010 Jun;31(6):1670-4.
According to the frequency of contamination accident for organic compounds in recent years, two kinds of organophosphorus pesticides dichlorvos and omethoate, as the simulated organic pollutants, were rapidly eliminated using spraying hydroxyl radical produced by strong electric-field ionization discharge method on an aluminium flat plate about 160 cm2. The high concentration aqueous *OH solution was produced from H2O(gas) and O2 with plasma reaction. In a condition, where pH is 6 and the initial densities of dichlorvos and omethoate on the simulation plane are both 60 microg x cm(-2), when the spray density of *OH reaches 3.9 microg x cm-2, removal efficiencies of dichlorvos and omethoate are 90%, and mineralization rates are 64% and 72%, respectively. The effect of pH for removal efficiency was also investigated. The results found that the removal efficiency of organophosphorus pollutants first decreased slowly and then increased fast with the increase of pH from 2 to 12 and the lowest removal rate appeared when pH close to neutral. The degradation rates of dichlorvos and omethoate both ascend by 21% and 26% respectively with pH 12 than that of pH 6. Four factors and three levels orthogonal test indicated that the degradation by *OH played a major role at the surface oxidation removal rapid of organophosphorus pollutants in a short period of time.
根据近年来有机化合物污染事故的发生频率，选用敌敌畏和氧乐果这两种有机磷农药作为模拟有机污染物，采用强电场电离放电法在面积约为160 cm²的铝板上产生的羟基自由基进行快速去除。通过H₂O（气态）和O₂的等离子体反应产生高浓度的·OH水溶液。在pH为6且模拟平面上敌敌畏和氧乐果的初始密度均为60 μg·cm⁻²的条件下，当·OH的喷淋密度达到3.9 μg·cm⁻²时，敌敌畏和氧乐果的去除率均为90%，矿化率分别为64%和72%。同时考察了pH对去除效率的影响。结果发现，随着pH从2增加到12，有机磷污染物的去除效率先缓慢下降后快速上升，在接近中性时去除率最低。与pH为6时相比，pH为12时敌敌畏和氧乐果的降解率分别提高了21%和26%。四因素三水平正交试验表明，·OH的降解作用在短时间内对有机磷污染物的表面氧化快速去除起主要作用。
