Biosorption of copper(II) from aqueous solutions by green alga Cladophora fascicularis

Biosorption is an effective means of removal of heavy metals from wastewater. In this work the biosorption behavior of Cladophora fascicularis was investigated as a function of pH, amount of biosorbent, initial Cu2+ concentration, temperature, and co-existing ions. Adsorption equilibria were well described by Langmuir isotherm models. The enthalpy change for the biosorption process was found to be 6.86 kJ mol(-1) by use of the Langmuir constant b. The biosorption process was found to be rapid in the first 30 min. The presence of co-existing cations such as Na+, K+, Mg2+, and Ca2+ and anions such as chloride, nitrate, sulfate, and acetate did not significantly affect uptake of Cu2+ whereas EDTA substantially affected adsorption of the metal. When experiments were performed with different desorbents the results indicated that EDTA was an efficient desorbent for the recovery of Cu2+ from biomass. IR spectral analysis suggested amido or hydroxy, C=O, and C-O could combine strongly with Cu2+.

Sorption and desorption of lead (II) from wastewater by green algae Cladophora fascicularis

Biosorption is an effective method to remove heavy metals from wastewater. In this work, adsorption features of Cladophora fascicularis were investigated as a function of time, initial pH, initial Pb(II) concentrations, temperature and co-existing ions. Kinetics and equilibria were obtained from batch experiments. The biosorption kinetics followed the pseudo-second order model. Adsorption equilibria were well described by the Langmuir and Freundlich isotherm models. The maximum adsorption capacity was 198.5 mg/g at 298 K and pH 5.0. The adsorption processes were endothermic and the biosorption heat was 29.6 kJ/mol. Desorption experiments indicated that 0.01 mol/L Na(2)EDTA was an efficient desorbent for the recovery of Pb(II) from biomass. IR spectrum analysis suggested amido or hydroxy, C=O and C-O could combine intensively with Pb(II). (C) 2006 Elsevier B.V. All rights reserved.

Biosorption of copper (II) and lead (II) from aqueous solutions by nonliving green algae Cladophora fascicularis: Equilibrium, kinetics and environmental effects

Biosorption of Cu2+ and Pb2+ by Cladophora fascicularis was investigated as a function of initial pH, initial heavy metal concentrations, temperature and other co-existing ions. Adsorption equilibriums were well described by Langmuir and Freundlich isotherm models. The maximum adsorption capacities were 1.61 mmol/ g for Cu2+ and 0.96 mmol/ g for Pb2+ at 298K and pH 5.0. The adsorption processes were endothermic and biosorption heats calculated by the Langmuir constant b were 39.0 and 29.6 kJ/ mol for Cu2+ and Pb2+, respectively. The biosorption kinetics followed the pseudo- second order model. No significant effect on the uptake of Cu2+ and Pb2+ by co-existing cations and anions was observed, except EDTA. Desorption experiments indicated that Na(2)EDTA was an efficient desorbent for the recovery of Cu2+ and Pb2+ from biomass. The results showed that Cladophora fascicularis was an effective and economical biosorbent material for the removal and recovery of heavy metal ions from wastewater.

Corrosion inhibition of mild steel in acidic solution by some oxo-triazole derivatives

The oxo-triazole derivative (DTP) was synthesized and its inhibiting action on the corrosion of mild steel in sulphuric acid was investigated by means of weight loss, potentiodynamic polarization, EIS and SEM. The results revealed that DTP was an excellent inhibitor and the inhibition efficiencies obtained from weight loss experiment and electrochemical experiment were in good agreement. Potentiodynamic polarization studies clearly revealed that DTP acted essentially as the mixed-type inhibitor. Thermodynamic and kinetic parameters were obtained from weight loss of the different experimental temperatures, which suggested that at different temperatures (298-333 K) the adsorption of DTP on metal surface obeyed Langmuir adsorption isotherm model. (C) 2009 Elsevier Ltd. All rights reserved.

The effect of some triazole derivatives as inhibitors for the corrosion of mild steel in 1 M hydrochloric acid

Corrosion inhibition by some new triazole derivatives on mild steel in 1 M hydrochloric acid solutions has been investigated by weight loss test, electrochemical measurement, scanning electronic microscope analysis and quantum chemical calculations. The results indicate that these compounds act as mixed-type inhibitors retarding the anodic and cathodic corrosion reactions and do not change the mechanism of either hydrogen evolution reaction or mild steel dissolution. The studied compounds following the Langmuir adsorption isotherm, and the thermodynamic parameters were determined and discussed. The effect of molecular structure on the inhibition efficiency has been investigated by ab initio quantum chemical calculations. The electronic properties such as highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) energy levels, energy gap (LUMO-HOMO), dipole moment and molecular orbital densities were calculated. (C) 2009 Published by Elsevier B.V.

Electrochemical, quantum chemical and SEM investigation of the inhibiting effect and mechanism of ciprofloxacin, norfloxacin and ofloxacin on the corrosion for mild steel in hydrochloric acid

The inhibiting effect and mechanism of 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylicacid(ciprofloxacin), 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid (norfloxacin) and (-)-(S)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7 H-pyrido(1,2,3-de)-1,4-benzoxazine-6 carboxylic acid (ofloxacin) on the corrosion of mild steel in 1 mol/L HCl have been studied using electrochemical method, quantum chemical method and SEM at 303 K. The potentiodynamic results showed that these compounds suppressed both cathodic and anodic processes of mild steel corrosion in 1 mol/L HCl. The impedance spectroscopy showed that R-p values increased, and C-dl values decreased with the rising of the working concentration. Quantum chemical calculation showed that there was a positive correlation between some inhibitors structure properties and the inhibitory efficiency. The inhibitors function through adsorption followed Langmuir isotherm, and chemisorption made more contribution to the adsorption of the inhibitors on the steel surface compared with physical adsorption. SEM analysis suggested that the metal had been protected from aggressive corrosion because of the addition of the inhibitors.

The inhibition of mild steel corrosion in 1 M hydrochloric acid solutions by triazole derivative

The title compound 1-(4,5-dihydro-3-phenylpyridine-1-yl)-2-(1H-1,2,4-triazole-1-yl)ethyl ketone (DTE) was synthesized and its inhibiting action on the corrosion of mild steel in 1 M hydrochloric acid solutions was investigated by means of weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and scanning electronic microscope (SEM). Results obtained revealed that DIE performed excellently as a corrosion inhibitor for mild steel in 1 M hydrochloric acid media and its efficiency attains more than 90.9% at 1.0 x 10(-3) M at 298 K. Polarization curves indicated that the inhibitor behave mainly as mixed-type inhibitor. EIS showed that the charge transfer controls the corrosion process in the uninhibited and inhibited solutions. Adsorption of the inhibitor on the mild steel surface followed Langmuir adsorption isotherm. And the values of the free energy of adsorption Delta G(ads) indicated that the adsorption of DTE molecule was a spontaneous process and was typical of chemisorption. (c) 2008 Elsevier B.V. All rights reserved.

Nicotinic acid as a nontoxic corrosion inhibitor for hot dipped Zn and Zn-Al alloy coatings on steels in diluted hydrochloric acid

The inhibition effect of nicotinic acid for corrosion of hot dipped Zn and Zn-Al alloy coatings in diluted hydrochloric acid was investigated using quantum chemistry analysis, weight loss test, electrochemical measurement, and scanning electronic microscope (SEM) analysis. Quantum chemistry calculation results showed that nicotinic acid possessed planar structure with a number of active centers, and the populations of the Mulliken charge, the highest occupied molecular orbital (HOMO), and the lowest unoccupied molecular orbital (LUMO) were found mainly focused around oxygen and nitrogen atoms, and the cyclic of the benzene as well. The results of weight loss test and electrochemical measurement indicated that inhibition efficiency (IE%) increased with inhibitor concentration, and the highest inhibition efficiency was up to 96.7%. The corrosion inhibition of these coatings was discussed in terms of blocking the electrode reaction by adsorption of the molecules at the active centers on the electrode surface. It was found that the adsorption of nicotinic acid on coating surface followed Langmuir adsorption isotherm with single molecular layer, and nicotinic acid adsorbed on the coating surface probably by chemisorption. Nicotinic acid, therefore, can act as a good nontoxic corrosion inhibitor for hot dipped Zn and Zn-Al alloy coatings in diluted hydrochloric acid solution. (c) 2007 Elsevier Ltd. All rights reserved.

Experimental and theoretical investigation of the adsorption behaviour of new triazole derivatives as inhibitors for mild steel corrosion in acid media

Three triazole derivatives (4-chloro-acetophenone-O-1'-(1',3',4'-triazolyl)-metheneoxime (CATM), 4-methoxyl-acetophenone-O-1'-(1',3',4'-triazolyl)-metheneoxime (MATM) and 4-fluoro-acetophenone-O-1'-(1',3',4'-triazolyl)-metheneoxime (FATM)) have been synthesized as new inhibitors for the corrosion of mild steel in acid media. The inhibition efficiencies of these inhibitors were evaluated by means of weight loss and electrochemical techniques such as electrochemical impedance spectroscopy (EIS) and polarization curves. Then the surface morphology was studied by scanning electron microscopy (SEM). The adsorption of triazole derivatives is found to obey Langmuir adsorption isotherm, and the thermodynamic parameters were determined and discussed. The relationship between molecular structure of these compounds and their inhibition efficiency has been investigated by ab initio quantum chemical calculations. The electronic properties such as the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) energy levels, energy gap (LUMO-HOMO), dipole moment and molecular orbital densities were computed. (c) 2007 Elsevier Ltd. All rights reserved.

Some new triazole derivatives as inhibitors for mild steel corrosion in acidic medium

Two triazole derivatives, 3,4-dichloro-acetophenone-O-1'-(1',3',4'-triazolyl)-methaneoxime (4-DTM) and 2,5-dichloro-acetophenone-O-1'-(1',3',4'-triazolyl)-methaneoxime (5-DTM) were synthesized, and the inhibition effects for mild steel in 1 M HCl solutions were investigated by weight loss measurements, electrochemical tests and scanning electronic microscopy (SEM). The weight loss measurements showed that these compounds have excellent inhibiting effect at a concentration of 1.0 x 10(-3) M. The potentiodynamic polarization experiment revealed that the triazole derivatives are inhibitors of mixed-type and electrochemical impedance spectroscopy (EIS) confirmed that changes in the impedance parameters (R-ct and C-dl) are due to surface adsorption. The inhibition efficiencies obtained from weight loss measurements and electrochemical tests were in good agreement. Adsorption followed the Langmuir isotherm with negative values of the free energy of adsorption Delta G(ads)(o). The thermodynamic parameters of adsorption were determined and are discussed. Results show that both 4-DTM and 5-DTM are good inhibitors for mild steel in acid media.

Electrochemical and thermodynamic investigation of diniconazole and triadimefon as corrosion inhibitors for copper in synthetic seawater

This paper presents the investigation of diniconzole and triadimefon as chemical corrosion inhibitors for freshly polished copper in synthetic seawater (3.5% NaCl solution). Determination of weight loss, polarization curves, electrochemical impedance spectroscopy (EIS), and SEM, were performed to analyze the inhibiting performance of these compounds. Polarization curves show that they act as mixed-type inhibitors. EIS indicates that an adsorption film of the inhibitors is formed on copper surface. The highest values of inhibition efficiency are respectively, 99.2% and 97.3% at 100 mg/L concentration. Thermodynamic calculation suggests that chemisorptions between the compounds and copper are accordance with Langmuir adsorption isotherm. (C) 2010 Elsevier Ltd. All rights reserved.

硫酸盐还原菌混合菌群胞外聚合物对Cu^2＋的吸附和机理

生物吸附法是处理含重金属废水的一种新兴的处理技术。微生物所分泌的胞外聚合物（EPS）在微生物吸附重金属中起重要作用。硫酸盐还原菌（SRB）混合菌群分泌的EPS能有效的吸附水溶液中的Cu^2＋，Langmuir等温方程和Freundlich等温方程都能拟合实验所得吸附数据，最大吸附容量达到478．47mg／gEPS。水溶液的初始pH值对EPS吸附Cu^2＋影响明显，在pH为7时，吸附效率最高，pH增减，吸附效率明显下降。SRB混合茵群分泌的EPS的FT—IR分析表明，EPS对Cu^2＋的吸附主要在于EPS中的蛋白质的酰胺（Ⅱ）、羧基、多聚糖的C-O-C、OH和脂类等基团对Cu^2＋的强络合能力.

水合氧化铁去除CU2+的实验研究

研究了实时生成的水合氧化铁(HFO)对Cu2+的去除.研究结果表明:生成的水合氧化铁是棕黄色无定形铁的氧化物,盐滴定方法测得其零电荷点PZC为8.28士0.02;它对Cu2+吸附的动力学特征受控于HFO的生成动力学,其吸附等温线可用Henry公式和类似Langmuir公式的叠加来拟合;随着吸附剂量的增加,它对Cu2+的吸附率和吸附量的影响分别呈现出指数形式(Y=aXb)的增加和减少.Cu2+从溶液中去除的可能机理包括表面络合反应、共沉淀、表面沉淀、Cu2+的水解作用、Cu2+的水解产物与水合氧化铁的絮凝作用等.

贵州红枫湖、百花湖沉积物-水界面营养元素（磷、氮、碳）的生物地球化学作用

富营养化是目前水资源管理的一个主要环境问题。水体中过量的营养元素是引起富营养化的根本原因，其中磷和氮是主要的控制因素。多数湖泊中磷是藻类自然生长的限制因子，因此多年来人们治理富营养化水体的主要策略是减少磷的排放，然而，通过此法成功恢复湖泊生态的例子屈指可数，一个主要的原因就是沉积物中的磷的再释放。因此，沉积物营养元素(尤其是沉积物－水界面上)的生物地球化学过程一直是湖泊科学研究的焦点。本次工作选择贵州的两个人工湖泊—红枫湖、百花湖，通过对磷、氮、碳在沉积物中的化学形态、垂直剖面等方面的研究，结合室内模拟实验和模式计算，揭示了沉积物早期成岩过程中磷、氮、碳的地球化学行为及其潜在的环境效应。尤其是对沉积物磷开展了较深入的研究。红枫湖、百花湖水体中的N／P为46～126，磷是湖泊的限制性营养因子。分析表明，红枫湖、百花湖沉积物中的全磷的平均含量为1300～1500μg.g~(-1)，与其它湖泊相比，红枫湖、百花湖具有较高的磷负荷。根据Ruttenberg提出的化学连续提取法(SEDEX)，可以把沉积物中的磷分为五种形态：(弱)吸附态磷、铁结合态磷、自生磷灰石磷、残留岩屑磷和有机磷。两湖沉积物中以有机磷和铁结合态磷为主，有机磷分别占全磷的60％(红枫湖)和50.3％(百花湖)，铁结合态磷为28.25％(红枫湖)和34％(百花湖)，这在其它湖泊是极少见的，红枫湖、百花湖沉积物磷具有很高的迁移活性。有机物质是沉积物磷的主要载体，沉积物中－部分有机质被保存下来，其余的矿化降解，同时释放出溶解磷(HPO_4~(2-))，这些溶解磷可以扩散到上覆水体为浮游生物吸收利用，或是以其它形态滞留在沉积物中。沉积物孔隙水中NO_3~-、SO_4~(2-)、Fe~(2+)、Mn~(2+)的剖面分布表明，红枫湖、百花湖沉积物最活跃的有机质降解发生在表层2厘米的沉积物内。根据孔隙水HPO_4~(2-)的浓度梯度，可以计算沉积物－水界面HPO_4~(2-)的交换通量(J_s)，红枫湖、百花湖沉积物-水界面磷的扩散通量(J_s)存在明显的季节性变化：在冬春季扩散通量最大，而夏秋季较小，这与传统的认识相反，我们认为这是由于表层沉积物中有机质的矿化降解有关。我们研究了沉积物吸附作用对沉积物磷循环的影响。吸附动力学实验表明，吸附的动力学过程可以用Langmuir或Freundlich方程描述；红枫湖、百花湖沉积物具有很大的理论吸附容量极值(红枫湖的S_m为21.05mgP.g~(-1),百花湖的S_m为15.83mgP.g~(-1));沉积物对磷酸盐的吸附主要是由于其中的未定型的铁氧化物矿物造成的；铁氧化矿物的吸附作用是沉积物中磷滞留的重要机制；经CDB去除铁氧化物处理后，沉积物吸附磷酸根的能力仅为原来的10％。对原状沉积物-界面水柱的释磷实验结果表明：好氧条件下沉积物的溶解磷的释放通量较高，而厌氧条件下相反较低。进一步说明了有机质降解在磷循环中的地位。将沉积物中磷的形态分析数据、孔隙水溶解磷以及吸附盐实验的数据，用于“扩散-平流-反应”模式，结果表明：红枫湖、百花湖沉积物表层有机质(磷)的降解释磷是沉积物-水界面磷交换通量的主要部分，由于沉积物表层易分解有机质的含量较高，铁氧化物的吸附不足以完全阻止沉积物磷酸盐的释放，有机质的氧化降解速率决定了释放通量的大小；而在表层以下的沉积物中铁氧化物的吸附作用是控制孔隙水溶解磷剖面分布的主要因素；红枫湖、百花湖沉积物的整个埋藏历史中(40年)，基本没有稳定自生磷灰石矿物的形成。红枫湖、百花湖沉积物全氮平均为沉积物干重的0.36～0.40％，表层含量为0.69～1.06％，沉积物中的含氮化合物主要85％以上是有机氮，沉积物全氮和有机氮呈现表层富集，随沉积深度增加而减少的剖面特征。红枫湖、百花湖沉积物对固定铵氮的能力较强，固定铵的绝对含量分别为434.05 mg.kg~(-1)和(16.94mg.kg~(-1)，分别相对于总氮含量的13.53％和12.53％。红枫湖、百花湖水体和沉积物孔隙水中氨态氮(NH_4~+)和硝态氮(NO_3~-)的剖面分布表明：在沉积物-水界面上发生着最剧烈的氮循环作用，这也是清除水体氮负荷的最彻底和唯一的机制。沉积物水界面起到向上覆水体的营养供给和对污染水体自然净化的双重功能。红枫湖、百花湖的沉积物柱芯上有机质剖面通常仅表现“降解阶段”和“堆积阶段”，对红枫湖HF980903-1-2柱芯的分析，发现红枫湖沉积物有机质(碳、氮)的降解代谢过程同样包括类似于洱海沉积物的“沉降－降解－堆积”三个阶段，我们认为是样品的分隔精度不足以反映沉积剖面的细节；同时也说明，红枫湖、百花湖沉积物有机质组成中有较多的“新鲜”、活性的组分，它们的快速降解使得沉积物中有机质不能长期保存。研究表明，经过10年堆积埋藏，沉积物有机质大约有35～76％被降解。上层沉积物中(活性)有机质的迅速分解，是引起沉积物－水界面强烈的营养元素循环的重要原因。剖面对比分析显示，红枫湖、百花湖沉积物有机物质分解过程中，有机碳、磷、氮的改造是不同步的，有机碳相对稳定，而含氮化合物和有机磷则相对易于降解。C_(Org): N_(Org): P_(Org)比值的分析结果表明：红枫湖、百花湖沉积物有机质的来源主要是来源于无纤维素植物。较高的C／N、C／P和较低的N／P，反映了小型湖泊受到较多的人为干扰和流域物质输入影响的特点。

溶液介质条件和腐殖影响下REE在水/粘土界面分配和分馏的实验研究

过去几十年，由于REE具有重要的物源和过程示踪的地球化学意义，又与核放射性元素（钢系元素）的地球化学结构类似，因此，稀土元素的表生地球化学分配和行为研究便成为微量元素地球化学研究的一个重要部分。目前"通过水体悬浮物吸附态REE组成变化分析研究水／微粒界面作用REE分异现象．的工作不少，但至今进行的胶体或其他微粒吸附REE的实验研究不多，且已有的实验未能对溶液介质条件（如pH、离子强度、阴离子、固／液比），尤其是天然有机物的控制机理进行系统研究，对所观察到的水体中REE及其他微量元素分布变化多样性的解释仍缺乏实验依据。本文用结晶良好且粘土矿物含量高的苏州高岭土、美国粘土协会高岭土（Kga-1b）和蒙脱土（Wwy-2）作为吸附剂，采用系列吸附实验定量研究了不同理化条件（如pH值、离子强度、固／液比）下，受溶液阴离子（Cl-、C1O4-、SO42-、HCO3-）和Fluka胡敏酸（HA）影响，REE在粘土／水界面的分配和分馏，并讨论了HA和粘土的相互作用及胡敏酸存在与不存在时的REE形态分布。得到以下几点重要认识，为合理解释地表水体中既E和其他微量元素分布变化的多样性提供了实验依据：1、REE在苏州高岭土／水界面的重现性实验结果为：稀土配分系数D的相对标准偏差最大值为Eu8.4％，其他大多介于5．0％和6．6％间。而稀土吸附率Rd的相对标准偏差最大值为D2.2％，其他大多＜2％。较小误差表明本次研究所用实验方法是可行的。2、REE在苏州高岭土／水界面的动力学实验结果表明：短时间内（几分钟）稀土快速吸附在高岭土：接着因为粘土的层状结构，在20h内粘土层间金属与REE发生交换，稀土分配系数变化较大；20h以后能达到稳定的吸附／解吸平衡。因此本次研究采用的平衡时间为24h。3、pH分别为4.5和6.5时REE在苏州高岭土冰界面的分配能用Langmuir吸附等温线模拟和MINEQL＋软件表达。与静电吸附相对应，pH值越高REE最大吸附量越大。同时REE浓度的差异造成了REE分馏，总的趋势是REE含量越高，分馏越不明显。4、近中性（pH＝6.5）条件下不同阴离子的存在对REE在苏州高岭土／水界面分配和分馏的影响表明：随阴离子（Cl-、ClO4-、SO42-）含量升高REE吸附率降低，其中SO42-对REE吸附的影响最大，说明Na＋质量效应和阴离子配合的影响；同时由于不同阴离子与轻重R陇的络合差异所致，阴离子含量越高，轻重稀土的分馏越明显（La／Yb＝0.14-0.96），一般为阴离子含量的增加使得重稀土更多的被吸附，其中C1-和SO42+的影响最为明显。HCO3-虽然与REE有较强配合，但可能由于我们的HCO3-实验浓度低（＜0.0O25mol／L），在我们的实验结果中其对REE吸附和分馏的影响较小。5、由于不同pH和介质条件下，REE的络合形态分布不同，它们可以影响其在水／粒界面的分配。应用MINEQL＋模型，考虑REE的氢氧化物、碳酸盐和腐殖酸的影响，研究了REE的形态分布，结果表明fIA的存在对REE形态有很大影响：在HA不存在时，pH7-8间REECO3＋为主要的REEs形态，在更低和更高pH值，REE主要存在形式分别为REE加和REE（CO3）2-；而当HA存在时，在1）H值3-9，REEHA成为主要形态，在低pH（＜3）和高pH（＞9）时REE3+和REE（CO3）2-分别为主要形态。6、在较宽的pH范围HA能吸附在粘土上意味着在大多数含HA的天然水体中，粘土表面被HA覆盖。随H增加粘土对HA的吸附降低，反应了配位体交换或表面络合反应引起的专属吸附，其他如疏水性、、腐殖物质的溶解和HA的结构变化可能也影响了吸附。HA含量、矿物表面积和离子强度等理化条件对HA吸附会产生影响，从而影响HA对粘土表面的覆盖和接下来的粘土对REE的吸附。7、溶液介质条件对REE在粘土（Kga-1b和SWy-2）／水界面分配和分馏的影响表明：主要与静电相互作用、离子交换反应相对应，除低PH外，REE在高岭土上的吸附表现出弱的pH依赖性；而随pH增加REE在蒙脱土上的吸附呈下降趋势，显示交换反应为吸附过程的主要因素。在两种粘土中REE吸附均为随离子强度增加而降低，反应了Na质量效应。8、腐殖物质在粘土表面的吸附改变了吸附剂的属性。HA存在时REE在固液界面的分配反应了REEHA在固液界面的分配和HA在高岭土或蒙脱土／水界面上的分配，其他如静电吸附等机制也影响了吸附：在高岭土中，HA会增加低pH（＜4）吸附，随pH增加（＞5）HA会降低吸附。与此不同，在整个PH范围（3-10），HA的存在明显降低了REE在蒙脱土上的吸附。REE吸附在高岭土上随队含量增加是先增加后降低。而蒙脱土实验中，在低HA含量（＜5mg／L）处，RE阮吸附率与HA含量增加呈线性降低至几个百分比，而在高队含量处，REEs吸，附率无明显变化。这些清楚地说明水体环境中有机物的存在通常降低微量金属吸，附在微粒上，增加微量金属在水体中的溶解量，从而促进微量金属在水体环境中的长距离迁移。9、HA存在和不存在时，吸附／解吸过程中的REE分馏随pH或离子强度的变化都不明显，但由于REE系列与腐殖物质和矿物络合的差异，会随队含量的变化发生明显变化。通常溶液中高队含量增加了LREE在高岭土／蒙脱土上的吸附。这些结果是在HA存在时，微粒相上产生LREE富集的一个实验证实，也和大多数天然水体中的REEs分馏相一致。