【作者】 郑萍英；

【导师】 孟昭福；

【作者基本信息】 西北农林科技大学 ， 环境工程， 2010， 硕士

【摘要】 土壤污染中有机物和重金属造成的危害最为严重,而土壤有机、重金属污染经常同时存在。两性表面修饰剂对有机物和重金属具有同时吸附固定的作用,非离子表面修饰剂对有机、重金属污染物也具有一定的效果。但非离子和两性表面修饰剂复配对土壤进行修饰,形成的两性-非离子复配修饰土对重金属、有机污染物具有什么样的吸附效果,目前尚未见到报道。本文采用批处理方法,首次研究了不同温度下,十二烷基二甲基甜菜碱（BS）单一修饰和不同比例十二烷基二甲基甜菜碱（BS）+辛烷基酚聚氧乙烯醚（OP）复配修饰（BP）塿土,分别对重金属Cd²⁺和有机污染物苯酚在单一、复合处理条件下的吸附动力学和平衡吸附特征,为两性-非离子复配修饰塿土对重金属和有机污染物的防治提供理论依据。研究所得主要结果如下:1.Cd²⁺吸附动力学结果表明,Cd²⁺单一处理和Cd²⁺+苯酚复合处理条件下,两性-非离子复配修饰土对Cd²⁺的吸附分为快速反应和慢速反应两个阶段。Cd²⁺单一条件下20℃时,Vf的大小顺序为100BS>50BS≈50+50BP>100+100BP≈100+50BP>CK>50+100BP,40℃时为100BS>100+50BP>100+100BP >50BS>50+100BP≈50+50BP>CK;在Cd²⁺+苯酚复合条件下,20℃、40℃时Vf的大小顺序均为100BS>100+50BP>100+100BP> 50BS>50+50BP>50+100BP>CK。说明两性-非离子复配修饰土中,BS具有加快Cd²⁺吸附的作用,而非离子修饰剂对Cd²⁺吸附速度起阻碍作用。双常数动力学模型是描述修饰土样吸附Cd²⁺的最佳模型。拟合参数A、B可作为描述两性-非离子复配修饰土对Cd²⁺吸附速度快慢的特征值。2.Cd²⁺平衡吸附结果表明,各修饰土对Cd²⁺的吸附能力均高于原土。两性-非离子复配修饰土对Cd²⁺的吸附是两种表面修饰剂共同作用的结果,总体上是随着BS修饰比例的增加,复配土对Cd²⁺的吸附量增大;而OP复配对复配土吸附Cd²⁺的影响因OP修饰比例和BS修饰比例的不同,具有不同的影响。Langmuir模型是描述复配修饰土样对Cd²⁺吸附的最佳模型。土样对Cd²⁺的吸附均为自发性反应,吸附反应均为吸热熵增控制过程。苯酚的加入对土样吸附Cd²⁺具有拮抗作用。3.苯酚吸附动力学结果表明,在苯酚单一处理和苯酚+Cd²⁺复合处理,两性-非离子复配修饰土对苯酚吸附同样具有快速反应（疏水性物理吸附）和慢速反应（化学吸附）两阶段特征。在苯酚单一处理和苯酚+Cd²⁺复合处理,20℃、40℃时,修饰土对苯吸附的Vt、Vf的大小顺序均为100+100BP>100+50BP>100BS>50+100BP>50+50BP> 50BS>CK。说明两性-非离子复配修饰土对苯酚的Vt、Vf起促进作用,增大BS或者OP修饰比例均能促进修饰土对苯酚的吸附。随温度由20℃升到高40℃,所有土样对苯酚吸附的Vt、Vf均呈下降趋势,呈现增温负效应。Cd²⁺的共存对修饰土吸附苯酚的速度具有一定的拮抗作用。双常数动力学模型是描述修饰土样吸附苯酚的最佳模型。4.苯酚平衡吸附结果表明,两性-非离子复配修饰土对苯酚的吸附能力明显增强,在苯酚单一处理和苯酚+Cd²⁺复合处理,在20℃、40℃两个温度下,其对苯酚的平衡吸附量顺序均为100+100BP>100+50BP>100BS>50+100BP>50+50BP>50BS>CK。增大BS或者OP修饰比例均能促进修饰土对苯酚的吸附。两性-非离子复配修饰土对苯酚吸附均为自发性反应。表观自由能变-ΔG的大小顺序与Henry模型拟合的分配系数K的顺序完全一致,证实吸附自发性越大吸附量越大的结果。各土样对苯酚吸附的均表现为增温负效应。Cd²⁺的共存对苯酚在修饰土中的吸附具有一定的拮抗作用。Henry模型是描述供试土样对苯酚吸附的最佳模型。更多还原

【Abstract】 The hazard of the organic matter and heavy metal are the most severe hazards in soil pollution. However, organic matter and heavy metal pollution ofen coexist at the same time. The amphoteric surfactant has the capability of adsorpting and fixing organic matter and heavy metal simultaneously. The nonionic surfactant also has certain effect to heavy metal and organic. Nonionic surfactant and amphoteric surfactant compound modify Lou soil and form amphoteric-nonionic co-modified soil. And the adsorption effect of co-modified soil to heavy metal and organic has not yet been reported at present. This article using batch treatment method, firt studied the adsorption kinetic and equilibrium adsorption of Cd²⁺ and phenol in single and complex treatment on Dodecane- Betaine （BS） single modified Lou soil and on different proportion of Dodecane-Betaine （BS）+ Octylphenol polyoxyethylene ether（OP） co-modified（BP） Lou soil at different temperatures. And all the experiments are to privide theory basis to the heavy metal and organic pollutant adsorption. The mainly obtained result are following:1. Cd²⁺ adsorption kinetic shows: in Cd²⁺ single treatment and Cd²⁺ and phenol complex treatment, all the adsorption processes of Cd²⁺ on BP Lou soil can be devided into two stages, the fast reactionVf and the slow reactionVs. The Vf order of Cd²⁺ on modified siols is 100BS>100+100BP>100+50BP>50+50BP>50+100BP>50BS>CK at 20℃and 100BS> 100+100BP>50BS>50+50BP>100+50BP>50+100BP>CK at 40℃in Cd²⁺ single treatment. The Vf order of Cd²⁺ on modified soils is 100BS>100+50BP>100+100BP>50BS>50+50BP> 50+100BP>CK at 20℃and 40℃in Cd²⁺ and phenol complex treatment. BS modified as a critical role to Vf of Cd²⁺on co-modified Lou soil, howere, OP modified as a hindrance effect. The double constant model is the best model to describe the adsorption kinetic curves of the all the soils. The fitting parameter A and fitting parameter B can become characteristic parameter to describe the adsorption velocity of Cd²⁺ on amphoteric-nonionic co-modified Lou soil.2. Cd²⁺ equilibrium adsorption shows: the capacity of Cd²⁺adsorption on all the modified soils is higher than that on unmodified soil. Amphoteric- non-ionic compound modified soils on the adsorption of Cd²⁺ is the interaction of two surface modifier results. With the increasing proportion of BS modification, the Cd²⁺adsorptive capacitity increased on compound soils; and OP co-modified has different influence on soil adsorption of Cd²⁺with the ratio of OP modified and the proportion of different BS modification in general. The Langmuir model is the best model to describe the equilibrium adsorption of Cd²⁺ on all the soils in Cd²⁺single treatment and Cd²⁺ and phenol complex treatment. The soils are spontaneity responded to the Cd²⁺ adsorption reaction. And the heat adsorption entopy increases. The jioning of phenol can hamper the adsorption of Cd²⁺.3. Phenol adsorption kinetic shows: in phenol single treatment and phenol and Cd²⁺ complex treatment, all the adsorption processes of phenol in BP co-modified Lou soil can be devided into two stages, the fast reaction（hydrophobic physisorption） and the slow reaction（chemical adsorption）. The BP co-modified play a the promote role to the Vt, Vf of phenol adsorption on BP co-modified soils. The increasing of BS or OP modified proportion can promote the soils to adsorb phenol. From 20℃to 40℃, the Vt, Vf of all the siols adsorb phenol assume the declining trend and present warming negative effect. And it’s the result of BS and OP synergy. The coexistent of Cd²⁺ play anti-function to the co-modified soil to adsorb phenol The order of phenol adsorption speed is 100+100BP>100+50BP> 100BS>50+100BP>50+50BP>50BS>CK at 20℃and 40℃. The double constant model is the best model to describe the adsorption kinetic curves of the all the soils. The fitting parameter A and fitting parameter B can become characteristic parameter to describe the adsorption velocity of phenol.4. Phenol equilibrium adsorption shows: the phenol adsorptive capacity on BS and OP co-modified soils obvious enhanced. The order of phenol adsorption capacity is 100+100BP>100+50BP>100BS>50+100BP>50+50BP>50BS>CK at 20℃and 40℃in all treatments. The soils are spontaneity responded to the phenol adsorption reaction in BP co-modified soil. And the apparent free energy–ΔG and the model fitting’s distribution coefficient K of Henry has the same change order. The results confirmed that the adsorption spontaneity is bigger, the adsorptive capacity is more bigger. All soils adsorp phenol show warming negative effect. The coexistence of Cd²⁺ has certain anti-function to the phenol adsorption on modified soils. Henry model is the best model to describe soils adsorp phenol model.更多还原