大同盆地砷中毒病区沉积物中砷的吸附行为和影响因素分析   总被引：3，自引：0，他引：3  

苏春利  Win hlaing  王焰新  徐芬  张随成 《地质科技情报》2009,28(3)

沉积物对砷的吸附-解吸作用是控制砷在地下水中的迁移和转化的决定性因素。对砷中毒重病区大同盆地山胡县沉积物中砷的吸附行为和影响因素研究结果表明,沉积物对砷的吸附符合Freundlich吸附等温模式,吸附量主要与沉积物颗粒大小、黏土矿物质量分数和类型、铁铝氧化物质量分数以及沉积物中As的质量分数有关,有机质质量分数对砷的吸附量影响需进一步深入研究。铝硅酸盐、铁铝氧化物质量分数较高且颗粒较细的黏土和亚黏土类沉积物对砷的吸附性较强;而铝硅酸盐、铁铝氧化物质量分数较低且颗粒较粗的细砂和粉砂类沉积物对砷的吸附性较差,其所处的含水层也是形成高砷地下水的主要含水层。pH值为5．5～8．0时,砷的吸附量最大。大同盆地高砷地下水pH条件非常不利于沉积物中砷的吸附,易形成高砷地下水。该区地下水10℃左右的温度条件非常有利于沉积物对砷的吸附,但由于影响因素较多,且地下水的温度在不同季节会发生一定的变化,其产生的影响还有待进一步研究。  相似文献   

高岭石和蒙脱石吸附Li~+的实验研究     

吴雅琴  赵志琦 《矿物学报》2011,31(2):291-295

为探讨粘土矿物从溶液中吸附锂的基本特征,选取蒙脱石和高岭石与合成的含锂人工海水(ρ(Li)=1.4mg/L)在室温下进行吸附反应,探讨其吸附平衡时间、pH和水岩比对吸附的影响。实验结果表明蒙脱石和高岭石与锂溶液在2 h内均达到吸附平衡。pH从4升高至8时,高岭石对锂吸附的量从33.2μg/g升高到72.4μg/g。而pH>8时,高岭石对锂吸附的量开始减小。水岩比明显的影响到高岭石的吸附能力。水岩比从50mL/g变化到100 mL/g和200 mL/g,其吸附量从25.2μg/g增加到58.8μg/g和142.6μg/g。这说明所用高岭石量足够与实验溶液达到吸附平衡,可以用本实验来研究吸附过程的锂同位素分馏特征。  相似文献   

天然沸石对Pb(Ⅱ)和Ni(Ⅱ)离子的吸附作用研究   总被引：18，自引：0，他引：18  

宋和付  夏畅斌  何湘柱  陈安国  黄念东 《矿产与地质》2000,14(4):276-278

在静态条件下,研究了沸石对重金属离子（如Ｐｂ＾２＋和Ｎｉ＾２＋）的吸附与交换。结果表明,沸石对重金属离子具有较强的吸附性能,ｐＨ值的影响吸附的主要因素,离子交换和表面络合反应是主要吸附形式。  相似文献   

黄土中硼的同位素组成变化及其气候示踪意义研究   总被引：1，自引：0，他引：1  

刘丛强  赵志琦  肖应凯 《第四纪研究》2000,20(4):394-394

自然界中硼的同位素组成变化很大(δ１１Ｂ＝－３０‰～＋４０‰),但在不问类型地质体中的分布或一定地质地球化学过程造成的分馏却有特定的范围。硼同位素分馏的主要原因是流体—固体反应体系的ｐＨ条件和水－岩比值变化。硼的这些特殊地球化学性质在不同地质地球化学作用示踪,特别是与流体作用有关的地球化学过程的研究中得到了广泛的应用。近年来有学者利用硼同位素组成示踪古海水的ｐＨ变化,但利用硼同位素示踪其它古环境或气候变化的研究却相当少。本文试图通过研究黄土中不同相态硼的同位素组成变化来识别黄土化学风化过程中流体介质的ｐＨ条件以及其它与风化作用强度有关的各种信息,并进一步发掘硼同位素组成变化在反映古气候、古环境  相似文献   

Adsorption of Pentachlorophenol onto Oxide and Clay Minerals： Surface Reaction Model and Environmental Implications     

WU Daqing DIAO Guiyi YUAN Peng PENG Jinlian 《《地质学报》英文版》2006,80(2):192-199

The adsorption of pentachlorophenol （PCP） onto quartz, kaolinite, illite, montmorillonite and iron oxides has been investigated by batch equilibrium techniques. The pH-dependent isotherms are curves with peak values, the position of which is at about pH = 5-6 depending on the mineral species. Based on distribution of both speciation of surface hydroxyls on minerals and PCP in solution a surface reaction model involving surface complexation and surface electrostatic attraction is presented to fit the pH-dependent isotherms, and both reaction constants are calculated. The results show that on quartz and phyllosilicate minerals the predominant adsorption reaction is surface complexation, meanwhile both of surface electrostatic attraction and surface complexation are involved on the iron oxide minerals. The reaction constants of surface electrostatic adsorption are usually one to three orders in magnitude, larger than that of surface complexation. The concentration-dependent isotherms can be well fitted by Langmnir equation with the correlation coefficient R〉0.93 for kaolinite and iron oxides. The maximum adsorption is found in the order： hematite 〉 lepidocrocite 〉 goethite 〉 kaolinite 〉 quartz 〉 montmorillonite ≈ illite, which can be interpreted by consideration of both reaction mechanism and surface hydroxyl density. The significant adsorption of PCP onto mineral surfaces suggests that clay and iron oxide minerals will play an important role as HIOCs are adsorbed in laterite or latertoid soil, which is widespread in South China.  相似文献   

Absorption of Arsenite on Several Iron （Hydro-）Oxides and Impact from Pre-processing Methods     

YE Ying JI Shanshan WU Daidai LI Jun ZHANG Weirui 《《地质学报》英文版》2006,80(2):200-205

The absorption reactions of arsenite on Fe （hydro-）oxides are studied. The three absorbent types are Fe（OH）3 gel and two Fe （hydro-）oxides, in which the Fe（OH）3 gel was dried in a microwave oven under vacuum at 80℃. It is found that pH changes from 9.71 to 10.36 in 6 minutes after the Fe （OH）3 gel was mixed with NaAsO2 solution, as the arsenite replaces the OH- in goethite and Fe（OH）3. At the 40th minute after the start of the reaction, pH decreases, which is most probably because that the monodentate surface complex of absorbed arsenite has changed into mononuclear-bidentate complex and released proton. The decline in pH values indicates not the end of the absorption but a change in the reaction type. Temperature and dissolved gas has little effect on these two types of reactions. The total absorption of arsenite increases after the absorbent is irradiated with ultrasound, which also lead to difficulty in separating the solids from solution. The absorption capacity for arsenite of Fe（OH）3 gel dried in a microwave oven under vacuum is 53.18% and 17.22% respectively better than that of Fe （OH）3 gel and gel dried at 80℃. The possible reasons are that the water molecules in the gel vibrates with high frequency under the effect of microwave irradiation, thereby producing higher porosity and improved surface activity.  相似文献   

Sorption behavior of o-nitrophenol on marine sediment     

杨桂朋吴萍  孙德信 《中国海洋湖沼学报》2005,23(2):246-251

Systematic study on sorption behavior of o-nitrophenol on marine sediments was conducted.Isotherms of sorption of o-nitrophenol on marine sediments could be described by Freundlich model; and the isotherm of sorption of o-nitrophenol on HCl-treated sediment could be described by Langmuir model. The sorption behavior was affected by various factors including organic carbon content, aqueous solution salinity,temperature, and acidity. The sorption amount of o-nitrophenol increased when salinity and acidity of the aqueous solution increase, but decreased with increasing temperature. Organic carbon content in sediments had apparent effect on the behavior except for HCl-treated sediments.  相似文献   

土颗粒沉降分析用水类型测试效果的检验比较     

张波  陈艳  陈兰芳 《上海国土资源》2008,(3):30-33

随着市场供水水源的多样化,密度计法颗粒分析试验用水类型也趋于多样化。在理论分析基础上,通过对比试验提出当前沉降分析试验用水种类选用的倾向性意见。  相似文献   

Removal of Lead,Copper, Zinc and Cadmium from Water Using Phosphate Rock   总被引：2，自引：0，他引：2  

Alessia CORAMI  Silvano MIGNARDI  Vincenzo FERRINI 《《地质学报》英文版》2008,82(6):1223-1228

Removal of Pb^2＋, Cu^2＋, Zn^2＋ and Cd^2＋ from aqueous solutions by sorption on a natural phosphate rock （FAP） was investigated. The effects of the contact time and initial metal concentration were examined in the batch method. The percentage sorption of heavy metals from solution ranges generally between 50% and 99%. The amount of sorbed metal ions follows the order Cu〉Pb〉Cd〉Zn. Heavy metal immobilization was attributed to both surface complexation of metal ions on the surface of FAP grains and partial dissolution and precipitation of a heavy metal-containing phosphate. The very low desorption ratio of heavy metals further supports the effectiveness of FAP as an alternative and low-cost material to remove toxic Pb^2＋, Cu^2＋, Zn^2＋ and Cd^2＋ from polluted waters.  相似文献   

天然磁铁矿处理含Hg（Ⅱ）废水实验研究   总被引：14，自引：0，他引：14       下载免费PDF全文

赵谨  鲁安怀  姜浩  陈浩  郑德圣  侯华丹 《岩石矿物学杂志》2001,20(4):549-554

利用重金属离子可在水合金属氧化物和氢氧化物矿物表面产生吸陵作用的原理，进行了天然磁铁矿处理含Hg(Ⅱ）废水的实验研究，结果表明：当温度为25℃，吸附平衡时间为60分钟、试样用量为20g/L，试样粒径为200目以下、pH值为6.40，离子强度为零时，Hg(Ⅱ）初始浓度为1.12mg/L的溶液的吸附率可达98%，使废水中Hg(Ⅱ）的浓度达到国家排放标准。pH值、离子强度、粒径、试样用量、废水浓度、温度、时间均对Hg(Ⅱ）的吸附率有一定的影响，其中pH值的影响最大，Hg(Ⅱ）在天然磁铁矿上的吸附等温曲线不同于Langmuir和Freundlich等温曲线，而是表现为台阶段，符合分级离子/配位子交换等温曲线。  相似文献