壬基酚在土壤中的降解和吸附特性  

Degradation and Adsorption of Nonylphenol in Soils

作　　者：王艳平[1] 杨正礼[1] 李正[1] 任海静[1] 

机构地区：[1]中国农业科学院农业环境与可持续发展研究所,北京100081

出　　处：《农业环境科学学报》2011年第8期1561-1566,共6页Journal of Agro-Environment Science

基　　金：国家科技基础性工作专项(2007FY210200)

摘　　要：采用室内模拟试验,研究了壬基酚(NP)在3种土壤中的降解和吸附特性。结果表明,NP在土壤中的降解分为快速和慢速降解阶段,半衰期分别为6.74～9.72d和70.02～78.77d。降解前期3种土壤中的降解速率相差较大,依次为黑龙江黑土>北京潮土>广西红壤,与土壤有机质含量相一致,随培养时间推移,降解速率差异减小。NP在土壤中具有不同结合状态及异构体降解性不同可能是出现慢速降解阶段的主要原因。土壤对NP的吸附较为符合Linear等温吸附方程(r≥0.9686),黑龙江黑土、北京潮土和广西红壤中吸附常数Kd值分别为65.52、31.66和32.71,黑龙江黑土对NP的吸附最强,广西红壤和北京潮土的吸附能力较为接近。各土壤理化性质参数中,以土壤有机质含量对NP吸附的影响最大(r=0.9950),阳离子交换量对吸附也有一定影响,粘粒含量和pH对吸附的影响较小。NP在3种土壤中的有机碳吸附常数KOC在3696.22～4334.51之间,移动性很弱,吸附自由能变化均小于40kJ·mol-1,NP在土壤中的吸附以物理吸附为主。Nonylphenol（NP） as one degradation intermediate of widely used nonionic surfactants occurs widespread in the environment.The objective of this study is to quantify degradation and adsorption of NP in three soils using the thermostatic cultivation approach and the batch equilibrium approach,respectively.It was showed that the degradation of NP was divided into fast-degradation phase and slow-degradation phase,and the degradation half-lifes（t1/2） in these two phases were 6.74~9.72 d and 70.02~78.77 d in different soils,respectively.The degradation rates of three soils was different in the early degradation phase,following order：Heilongjiang black soilBeijing fluvo-aquic soilGuangxi red soil,which was consistent with the soil organic matter content.However,the gap among three degradation rates narrowing with the cultivation time going on.The different combination states of NP with soils and different degradabilities of various NP isomers might be the main reason for the occurrence of slow degradation phase.The adsorption of NP in three soils was tested with six different initial concentrations resulted in linearly fitted isotherms with adsorption constant（Kd） ranged from 31.66 to 65.52.NP was most easily adsorbed by the Heilongjiang black soil.Adsorption of NP was primarily related to soil organic matter content.Since Koc ranged from 3 696.22 to 4 334.51 in three soils,NP was not easy to migrate in soil.The adsorption of NP by soil belonged to physisorption with changes of free energy less than 40 kJ·mol-1.

关 键 词：壬基酚 土壤 降解 吸附 

分 类 号：X53[环境科学与工程—环境工程]