摘要
在不同照射时间、pH和溶解氧浓度下,研究了从加拿大魁北克省Rimouski河提取的黄腐酸(RRFA)在模拟太阳光照射过程中对苯并(α)芘结合性质的影响。结果表明,RRFA经模拟太阳光照射后,其与苯并(α)芘的结合系数KOC下降。光化过程中RRFA的相对分子质量或SUVA270与KOC之间有良好的指数回归关系。在pH4.1～8.0范围内,以光照后的pH条件下测定照射样品的KOC,KOC平均下降47.4%±17.4%;以光照前的pH条件下测定照射样品的KOC,KOC平均下降48.7%±16.9%。溶解氧浓度的升高能加速RRFA的光氧化降解过程,与相应的未照射样品相比,空气饱和与氧气饱和条件下照射后的KOC分别下降30%和74%,氮气饱和条件下照射后的KOC升高122%。
The effects of photochemical degradation of Rimouski River Fulvic Acid （RRFA） on the binding property of benzo（α） pyrene were investigated under solar-simulated irradiations, in which the influence of O2 abundance, irradiation time, and pH were discussed in details. The irradiations substantially decreased the binding coefficient K0c, which was positively correlated with the molecular weight and aromaticity of fulvic acid in the time-course of irradiation. K0c decreased averagely 47.4% ± 17.4% （determined at the initial pH） and 48.7% ± 16.9% （determined at the post-irradiation pH） respectively in the pH range of 4. 1 to 8.0. Increasing O2 abundance accelerated the decrease of the binding coefficient as a result of enhanced photo-degradation of fulvic acids. Compared with the unirradiated sample, the binding coefficient of RRFA-BaP under air-saturated and oxygen-saturated irradiations decreased 30% and 74%, respectively, while it increased 122% under nitrogen- saturated irradiation.
出处
《地球化学》
CAS
CSCD
北大核心
2007年第4期363-367,共5页
Geochimica
基金
加拿大自然科学与工程研究理事会(NRSEC)(213327)
关键词
光化学
黄腐酸
模拟太阳光
结合系数
苯并(α)芘
photochemistry
fulvic acid
solar-simulated irradiation
binding coefficient
benzo（α）pyrene
