土壤对氟离子吸附与解吸的动态土柱法研究

用饱水动态土柱法对氟离子的吸附与解吸特征及其反应动力学特征进行了初步探讨。结果表明，氟离子的吸附与解吸特征可分别用Ｌａｎｇｍｉｕｒ模型和Ｆｒｅｎｄｌｉｃｈ模型来表征。而氟的吸附与解吸反应动力学均可用Ｅｌｏｖｉｃｈ方程来描述。吸附与解吸过程是一个由反应速率控制的不可逆过程。     

藻吸附金属离子的研究—斜生栅藻富集金

发展了一种新的金属离子的分离富集方法－微生物吸附法，重点研究了斜生栅藻对的吸附和解吸条件，其吸附率和解吸回收率均大于９５％，首次用藻类分离富集了地质样品中的痕量Ａｕ，其标准加入回收率大于９１％，用原子吸收法测定标样中痕量金，其结果与推荐值相符，此外，机理探说明：斜生栅藻富集金的过程起主要作用的是络合吸附，随吸附时间的增长也发生生物吸收作用，同时，伴有氧化还原反应发生。     

泥沙吸附重金属污染物室内静态试验研究

从吸附反应动力学方程和质量守恒方程出发,导得室内静态试验中泥沙吸附量和水相重金属浓度随时间变化的计算公式,并得出泥沙平衡吸附量和水相平衡浓度随泥沙吸附特性、水相重金属离子初始浓度和泥沙浓度变化的计算公式。结合室内试验,认为泥沙浓度不影响吸附特性参数,如饱和吸附量b、吸附-解吸速率常数k及吸附速率系数k1.     

Groundwater contaminant transport including adsorption and first order decay

This study deals with the transport of a contaminant in groundwater. The contaminant is subject to first order decay or linear adsorption. Its displacement can be modeled by a random walk process in which particles are killed at exponentially distributed times. Dirichlet problems are derived for the rate and mean time at which contaminated particles reach a particular part of the boundary of a certain domain. These Dirichlet problems are solved asymptotically for two types of 2D-flow patterns: flow parallel to the boundary of a domain and arbitrary flow towards a well in an aquifer.     

混合菌种对地下水中三氯乙烯的生物降解和吸附解吸的实验研究

由于氯代有机溶剂的大量使用和不合理的处置 ,致使三氯乙烯 (以下简称TCE)成为地下水中常见的有机污染物。本实验以TCE为靶污染物 ,采用批试验方法 ,研究了灭菌后的混合菌种对不同浓度TCE的吸附影响。实验结果表明 :当TCE浓度在 10～ 2 0 0mg l范围内 ,TCE的吸附模式符合Cs =0 17976C2 36 39e 等温方程 ;TCE的解吸模式符合C =0 0 2 987C2 1 46 1 e 等温方程 ;吸附在 15min内平衡 ;解吸在 1h内平衡。     

Mechanism of cadmium resistance and adsorption of a yeast strain Rhodotorula sp. Y11

The mechanism of cadmium resistance of a yeast strain Rhodotorula sp. Y11 isolated from mine soil was investigated. We found that the yeast cells treated with different methods showed different cadmium-adsorption models. Grown in medium supplied with 100 mg/L of cadmium, 3.29% of the cell-absorbed cadmium was accounted in the cytoplasm. However, only 1% was taken into the cytoplasm and 99% was bound to the cell wall using the lyophilized biomass to adsorb cadmium in double distilled water. Treatments with alkali, ethanol-chloroform and proteinase showed different influences on the biosorption of whole cells and isolated cell walls. FT-IR analysis showed that acetyl of chitin was the active compound in the cells to absorb cadmium. The production of Metallothioneins, proteins related to the resistance to heavy metal in yeast, was evidently induced by cadmium, achieving 638.8 μg/g wet weight, which was about 85 folds higher than that in the uninduced biomass and was also much higher than that reported previously. The molecular weight of Metallothioneins was 6500 Da estimated by SDS-PAGE.     

Experimental research on adsorption/desorption for petroleum pollutants in the soil in Daqing oilfield

The Daqing oilfield is one of the biggest oilfields in the world. It has been exploited for several decades, which brings serious pollution to local natural environment. The crude oil on ground which is produced in the process of oil production contains various organic pollutants. The petroleum pollutants tend to adsorb, desorb, biodegrade and photolyze and so on in the soil, but adsorption/desorption is a pair of extremely important environment geochemistry behavior. In order to master the rule of petroleum pollutants migration and transformation in the soil environment, and provide scientific evidence for the prevent research project on petroleum pollution treatment in the Daqing oilfield, the chemozem was selected as the experimental sample, which is a kind of representative soil in the Daqing oilfield. The factors affecting adsorbent and desorption＇s characteristics were discussed, including pH of the soil, the concentrations of suspended particulates and temperature. The oscillation-equity was used in the experiment. The mechanism and dynamics process of the adsorption/desorption were researched. The results showed that adsorbing of the petroleum pollutants on the chemozem sediment is a kind of physical adsorption phenomenon. The adsorption function comes from the hydrophobic and sticky character of the petroleum its self. The velocity of adsorption and desorption is almost equivalent, both concentrations of water in the soil are close to the balance in two hours, thus they achieve homeostasis in three hours. The process of adsorption of the petroleum pollutants responses to Herry isothermal model, with increasing pH, concentration of suspended particulates and temperature, the quantity of adsorption show a descending trend. However, desorption is a contrary course of adsorption in the experiment. Due to various influenced phenomena reflect that the soil in the Daqing oilfield has factors, the quantity of desorption shows an ascending trend. These strong adsorption ability to petroleum pollutants.     

Seasonal variations of adsorption/desorption equilibrium concentrations of P at water-sediment interface in the Meiliang Bay, Taihu Lake, China

Seasonal variations of adsorption/desorption equilibrium were investigated by collecting overlying water and seasonal sediment from the Meiliang Bay, Taihu Lake, China. At the same time, seasonal variations of TP and P fractions＇ concentrations in the initial and end of adsorption experiment were also carried out. In addition, the effects of temperature on the P translocation process were also conducted and discussed. The following conclusions were obtained： The sequence of adsorption/desorption equilibrium concentrations of P at water-sediment interface was spring〈winter〈autumn. In sediment the concentrations of TP decline. Concentration P decreased with temperature.     

成都长安垃圾填埋场填土料对污染物质的吸附试验研究

现场调查和室内实验表明,作为垃圾填埋结构之一的填土层对渗滤液污染物质起着不可低估的净化作用。本文在详细研究了成都市长安垃圾填埋场填土料的矿物组成、化学成分和颗粒分布特征的基础上,选取渗滤液中的主要污染物质ＮＨ＋４进行了静态和动态吸附试验。结果表明：土料对ＮＨ＋４有较强的吸附能力,平均吸附量为２．５２ｍｇ·ｇ－１,吸附速率为１．１２５ｍｇ·ｈ－１·ｇ－１,吸附过程符合Ｌａｎｇｍｕｉｒ方程。填土层在工作过程中形成了上部饱和层、中部工作层、下部新料层的三个部分,吸附机理以置换Ｃａ２＋,Ｍｇ２＋等阳离子为主的离子交换作用,出水中ＮＨ＋４与Ｃａ２＋,Ｍｇ２＋等阳离子呈现显著的负相关关系。     

Experimental study on the competitive adsorption of metal ions onto minerals

The study on the competitive adsorption shows that the magnitude order of metal ions adsorbed onto oxide and silicate minerals in near-neutral solution with low ionic strength is in mole/nm² as follows: CaCO₃ > quarte > hydromuscovite > kaolinite > Ca-montmorillonite > goethite > gibbsite. These minerals can be divided into three groups according to their surface equilibrium constantsK _M of the adsorption reactions, which are the function of the dielectric constants ε of the absorbent minerals. The relationships between constantsK _M and mineral dielectric constants ε are described as follows: lgK _M ¹ = 7.813-26.15/ε lgK _M ² = 9.030-26.15/ε lgK _M ³ =11.63-26.15/ε for the adsorption reaction: >SO^- + Mⁿ⁺≥SOM^n-1)+ (n = 1, 2, 3) The first group of minerals include quartz, goethite, 1:1 phyllosilicates and other oxide minerals; the second: gibbsite, brucite and 2:1 phyllosilicates; the third: carbonate, sulphate and phosphorate minerals. The appearance reaction constants have a variation of magnitude ±0.5 for different metal ions with the same mineral. This project was financially supported by the National Natural Science Foundation of China (No. 49572091).