海水中常见组分对两种有机磷光解动力学影响

The Effect of Common Components in Seawater on the Photolysis Kinetics of Two Organophosphorus Compounds

本文以葡萄糖-6-磷酸(G-6-P)和2-氨基乙基膦酸(2-AEP)为有机磷化合物代表,利用室内模拟实验,考察腐殖酸HA、Fe^(3+)、Cl^(-)、SO_(4)2-等对海水中有机磷光解过程的影响;借助自由基淬灭实验,明确·OH、^(1)O_(2)对二者在不同介质中光解的作用。结果表明,紫外光(700W)照射下,G-6-P和2-AEP光解速率曲线可由一级动力学方程描述,纯水中G-6-P光解速率常数为0.24 h^(-1),高于2-AEP光解速率常数0.12 h^(-1),HA对G-6-P光解呈抑制作用,且浓度越高,抑制越强,其对2-AEP的抑制作用强于对G-6-P;Fe^(3+)能显著促进G-6-P光解,但对2-AEP降解影响较小。NaCl(31.9)对G-6-P、2-AEP光解的抑制效应较强,Na_(2)SO_(4)(31.9)对G-6-P光解无明显影响。纯水介质中,·OH、^(1)O_(2)对G-6-P光解贡献率大于2-AEP,·OH、^(1)O_(2)对G-6-P在纯水中光解贡献率为90%、88%,高于天然海水中的60%、56%。

The effects of humic acid(HA),chloride ion(Fe^(3+)),sulfate ion(SO_(2)-4)and chlorid ion(Cl^(-))on photolysis of organophosphorus compounds represented by Glucose-6-phosphate(G-6-P)and 2-aminoethylphosphonic acid(2-AEP)were studied.The effects of hydroxyl radicals(·OH)and Singlet oxygen(^(1)O_(2))during the photolysis in different media were investigated.The photolysis rate curves of G-6-P and 2-AEP under UV light(UV)irradiation could be described by the first-order kinetic equation.In pure water,the photolysis rate constants of G-6-P was 0.24 h^(-1),which was higher than that of 2-AEP(0.12 h^(-1)).HA inhibited the photolysis of G-6-P,and the inhibitory effect strengthened with HA concentration increasing.The inhibition of HA on 2-AEP photolysis was higher than that of G-6-P.Fe^(3+)significantly promoted the photolysis of G-6-P,while its effect on 2-AEP seemed relatively less.Sodium chloride(NaCl,31.9)inhibited the photolysis of G-6-P and 2-AEP,while sodium sulphate(Na_(2) SO_(4),31.9)showed no obvious effect on the photolysis of G-6-P.Compared with 2-AEP,·OH、^(1)O_(2) contri-buted more to the photolysis of G-6-P.For G-6-P,the contribution rates of·OH and ^(1)O_(2) were 90%and 88%in pure water,which were higher than those in natural seawater(60%、56%).