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Pedosphere 1998年第4期8卷 297-304页

作者： ZHANG mINGKUI m. J. WILSON HE ZHENLI L. CLARK and D. m. L. DUTHIE (Department of Soil Science and Agricultural Chemistry, Zhejiang Agricultural University, Hanyzhou 310029 China) (Soils and Soil microbiolopy Division, macaulay Land Use Research Institu Department of Soil Science and Agricultural Chemistry Zhejiang Agricultural University Hangzhou 310029 China Soils and Soil microbiology Division Macaulay Land Use Research Institute Aberdeen AB9 2QJ United Kingdom

The phosphate adsorption and surface charge characteristics of the tropical and subtropical soils derived from different parent materials in China were determined, and their relations to soil mineralogy were *** results showed that all soil phosphate adsorption curves were well fitted by freundlich equation and Langmuir equation. The maximum buffering capacity of P ranged from 66 to 9880 mg kg-1, with an increasing order of purple soil, skeletal soil, red soil, lateritic red soil, yellow soil and latosol; and the highest value was 149 times the lowest value, which indicated great differences among these soils in phosphate adsorption and supplying characteristics. The pHo (zero point of charge) values obtained by salt titrationpotential titration varied from 3.03 to 5.49, and the highest value was found in the latosol derived from basalt whereas the lowest value was found in the purple soil. The correlation analysis indicated that the main minerals responsible for phosphate adsorption in the soils were gibbsite, amorphous iron oxide and kaolinite; and the pHo was mainly controlled by kaolinite, gibbsite and oxides.

关键词：矿物学磷酸盐吸附 PH值热带土壤亚热带土壤华南地区

Removal of Pb(II) from Aqueous Solution by <i>Portulaca oleracea</i>Leaves: Kinetic, Equilibrium and Thermodynamic Studies

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American Journal of Analytical Chemistry 2013年第7期4卷 27-32页

作者： m. A. Ackacha Faculty of Education Sebha University Sabha Libya

Portulaca oleracea leaves are tested as an agriculture adsorbent material for reducing Pb(II) from aqueous solutions. The pH of solution, adsorbent dose, shaking speed and particles size of adsorbent were constants at all adsorption experiments. Effects of contact time on adsorption capacity of Pb(II) onto Portulaca oleracea leaves were studied. The adsorption capacity increased as the contact time increased and reached equilibrium at one hour. Kinetic models including a first-order, pseudo-second-order and intra-particle diffusion equations were selected to follow the adsorption process. The process follows a pseudo-second-order kinetic and the intra-particle diffusion is the main step to interpret the mechanism of adsorption. Langmuir, freundlich and Dubinin-Radush Kevich (D-R) isotherm models were applied to describe adsorption equilibrium data. Results proved that the Langmuir isotherm model gave an acceptable fit to the experimental data more than freundlich isotherm model. maximum adsorption capacities obtained were 192.3, 333.3 and 434 mg/g at 295, 303 and 310 K, respectively. According to D-R isotherm data, the adsorption process is classified as physical adsorption. Thermodynamically, the adsorption process is non spontaneous, endothermic and random in nature.

关键词： Portulaca oleracea Langmuir freundlich Isotherm Lead Adsorption

Equilibrium Isotherms and Kinetic Studies of Removal of methylene Blue Dye by Adsorption onto miswak Leaves as a Natural Adsorbent

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Journal of Environmental Protection 2011年第6期2卷 817-827页

作者： Taha m. Elmorsi 不详

In this research miswak leaves, agriculture wastes, available in large quantity in Saudi Arabia, was used as low-cost adsorbent for removing methylene blue (mB) dye. Equilibrium behavior of miswak leaves was investigated by performing batch adsorption experiments. The effects of [mB] 0, pH, contact time and adsorbent dose were evaluated. An alkaline pH (10.6) was favorable to the adsorption of mB dye. Adsorption isotherm models, Langmuir, freundlich and Temkin were used to simulate the equilibrium data. Langmuir equation was found to have the highest value of R2 compared with other models. Furthermore, it was found that miswak leaves have a high adsorptive capacity towards mB dye (200 mg/g) and show favorable adsorption of mB dye with separation factor (RL mB adsorption onto miswak leaves. Adsorption process undergoes pseudo-second order kinetic as proved by the high value of R2 and the low value of sum of squared error (SSE percentage). Results indicated that intra-particle diffusion is not the limiting step, and the adsorption process is spontaneous as indicated by the negative value of the .

关键词： miswak Leaves Salvadora Persica methylene Blue Adsorption Isotherms Adsorption Kinetics

Synthesis of Nano-Titanium Tannate as an Adsorbent for Crystal Violet Dye, Kinetic and Equilibrium Isotherm Studies

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Journal of Environmental Protection 2015年第12期6卷 1454-1471页

作者： Taha m. Elmorsi Chemistry Department Faculty of Science Al-Azhar University Cairo Egypt

The purpose of this study was to prepare nano-titanium tannate complex (TTC) and to investigate its adsorption capacity for removal of cationic dyes such as crystal violet (CV) dye. The morphology and the main elements of TTC adsorbent were characterized by scanning electron microscopy (SEm-EDS), while its crystal structure was characterized by X-ray diffraction (XRD). Also, FT-IR spectroscopy study structural aspects of TTC. A “cotton-ball”-like and porous surface structure of titanium tannate complex (TTC) with nanoparticle size of 16.18 nm show high capability for absorbing crystal violet dye. The effect of several parameters such as contact time, initial concentrations of CV, solution pH and the amount of TTC was investigated. Three different kinetic equations such as pseudo-first order, pseudo-second order and intraparticle diffusion were used to study the order and the mechanism of the adsorption process. The adsorption of CV dye followed pseudo- second order equation. moreover, equilibrium data were tested with four adsorption isotherm models namely, Langmuir, freundlich, Temkin and Dubinin-Radushkevich (D-R). Langmuir was the best fit for the data with maximum capacity as 58.8 mg/g. The results of Separation factor, Surface coverage and standard free energy (ΔG°) indicated that adsorption of CV onto TTC was favorable with fast rate and spontaneous physical adsorption process.

关键词： Titanium(III) Tannate Complex (TTC) Crystal Violet Adsorption Kinetics Adsorption Isotherms

Removal of Cesium on Polyaniline Titanotungstate as Composite Ion Exchanger

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Advances in Chemical Engineering and Science 2012年第1期2卷 166-179页

作者： I.m. El-Naggar E. S. Zakaria I. m. Ali m. Khalil m. F. El-Shahat 不详

Polyaniline titanotungstate (PATiW) was synthesized by the sol-gel method. Adsorption isotherm studies of Cs+ from aqueous solution are described. Elemental Composition, chemical solubility, ion-exchange capacity (IEC) and pH titration are studied. Distribution coefficients (Kd) for ten metal ions have been determined. It was found that the polyaniline titanotungstate has high affinity and high selectivity for Cs+. The material was high separation of Cs+ from other metal ions. The adsorbent capacity was determined using the freundlich and Langmuir adsorption isotherm models. The Cs+ adsorption isotherm data fit best to the freundlich isotherm model. The maximum Cs+ uptake of polyaniline titanotungstate was found 217 mg/g. A column tests were performed to determine the breakthrough curves with varying bed depths and flow rates in different solutions. The results show that the half breakthrough time increases proportionally with increasing bed depths. Kinetic studies for removal cesium from milk were investigated.

关键词： Synthesis Separation Polyaniline Titanotungstate Cesium

用于去除水溶液中铜离子的环境友好的聚(对苯二胺)及其壳聚糖复合材料的制备和表征（英文）

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Transactions of Nonferrous metals Society of China 2015年第11期25卷 3808-3819页

作者： N.A.ABDELWAHAB E.A.AL-ASHKAR m.A.ABD EL-GHAFFAR Polymers and Pigments Department National Research Centre Spectroscopy Department Physics Division National Research Centre

利用过硫酸铵作为氧化剂,在壳聚糖(Chi)中用对苯二胺(PPPDA)原位化学氧化聚合反应制备聚(对苯二胺)/壳聚糖复合材料。在添加铜前后,利用FT-IR光谱和SEm表征对苯二胺和对苯二胺/壳聚糖复合材料。利用振荡吸附法,采用1 g/L对苯二胺和对苯... 详细信息

利用过硫酸铵作为氧化剂,在壳聚糖(Chi)中用对苯二胺(PPPDA)原位化学氧化聚合反应制备聚(对苯二胺)/壳聚糖复合材料。在添加铜前后,利用FT-IR光谱和SEm表征对苯二胺和对苯二胺/壳聚糖复合材料。利用振荡吸附法,采用1 g/L对苯二胺和对苯二胺/壳聚糖复合材料,在PPPDA和PPPDA/Chi复合材料的pH分别为5.0和6.0的条件下,吸附360 min,可以得到最大的铜去除量。PPPDA显示最大吸附量为650 mg/g,而复合材料的吸附量达到573 mg/g。实验数值与freundlich等温方程和伪二阶动力学模型吻合良好。含铜的对苯二胺及其复合材料可以被有效地再利用4个循环。相对于无吸附的状态,吸附获得的铜具有高的革兰氏阳性和革兰氏阴性菌抑菌效果。

关键词：铜去除吸附聚(对苯二胺)/壳聚糖复合材料动力学等温线

运用环保吸附剂墨角藻和响应面法去除Cr(Ⅵ)和皮革染料

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中国皮革 2014年第17期43卷 47-50页

作者： m. Cobas m. A. Sanromán m. Pazos 维哥大学化学工程系西班牙维哥36310

采用墨角藻作为低成本的吸附剂处理制革废水。制革废水呈黄棕色且具有高浓度的Cr(Ⅵ)。因此,使用Cr(Ⅵ)溶液和4种颜料混合,模拟制革废水。基于Box-Behnken设计,采用响应面分析法优化吸附过程。选择初始溶液pH、生物质含量和预处理中CaCl... 详细信息

采用墨角藻作为低成本的吸附剂处理制革废水。制革废水呈黄棕色且具有高浓度的Cr(Ⅵ)。因此,使用Cr(Ⅵ)溶液和4种颜料混合,模拟制革废水。基于Box-Behnken设计,采用响应面分析法优化吸附过程。选择初始溶液pH、生物质含量和预处理中CaCl2溶液浓度为主要参数。统计学分析结果表明:pH值的影响可以忽略不计,生物质含量和CaCl2溶液浓度是主要的影响参数。在最优条件下,98%的Cr(Ⅵ)和88%的染料被除去。相比Temkin,Langmuir和D-R等温模型,freundlich等温模型能够很好地拟合平衡数据。另外,证实了吸附后的吸附剂可以作为糙皮侧耳菌生产酶的支持基质。

关键词：方差分析生物吸附 Cr(VI) 皮革染料墨角藻

Cadmium Removal from Aqueous Solution by a Tunisian Smectitic Natural and Activated Clay: Thermodynamic Study

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Journal of Encapsulation and Adsorption Sciences 2011年第4期1卷 65-71页

作者： L . Khalfa m. Bagane 不详

The removal of heavy metals from industrial waste streams has become one of the most important applications in wastewater treatment in terms of protecting public health and environment. The recovery of metals present in the industrial effluents by adsorption onto natural materials constitutes a technological option increasingly studied throughout the world. However, the implementation of such process on an industrial scale requires the use of adsorbents easily available and inexpensive. Clay in these two forms natural and activated answers very well to these two requirements. The present research aimed the study of the capacity of fixing of cadmium present in aqueous solution, by two types of clay: natural and activated. The adsorption capacity of adsorbent was investigated using batch experiments. The influence of pH, temperature and adsorbent dose were investigated and the experimental data obtained were evaluated and fitted using adsorbent equilibrium isotherms. Adsorption isotherms of cadmium onto natural and activated clay were determined and correlated with common isotherm equations such as the Langmuir and freundlich models. The Langmuir model agrees very well with experimental data. The thermodynamic parameters obtained indicated that the adsorption of cadmium ions onto natural clay was a spontaneous and an endothermic process.

关键词： Adsorption Isotherms Cadmium Naturel Clay Activated Clay modeling

Hydrothermal Synthesis and Characterization of a Novel Zirconium Oxide and Its Application as an Ion Exchanger

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Advances in Chemical Engineering and Science 2011年第1期1卷 20-25页

作者： mamdouh m. Abou-mesalam 不详

A novel hydrothermal zirconium oxide (ZrO2) ion exchange material was successfully synthesized by hydrothermal technique. The material has been characterized using different tools such as thermal analysis (DTA-TGA), FT-IR and X-ray diffraction studies. The results show that the prepared ZrO2 is pure and with a unique shape and it belongs to the hexagonal system. Chemical resistively of the material for various media such as, water, acids and bases have been assessed. The capacity of ZrO2 ion exchanger for Na+, Cu2+, Ni2+ and Zn2+ ions at natural pH has been determined. The effect of heating treatment for ZrO2 on ion exchange capacity was studied. The sorption/ion exchange behaviour of Cu2+, Ni2+ and Zn2+ ions towards ZrO2 in dif-ferent pH media has been investigated. The distribution coefficients and separation factors were determined. Finally, freundlich isotherms for Cu2+, Zn2+ and Ni2+ ions on hydrothermal ZrO2 ion exchanger were inves-tigated and the freundlich isotherm constants were conduced.

关键词： Hydrothermal Synthesis Zirconium Oxide Ion Exchanger

Adsorption of malachite Green from Aqueous Solutions onto Rice Husks: Kinetic and Equilibrium Studies

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Journal of Environmental Protection 2017年第3期8卷 215-230页

作者： V. m. muinde J. m. Onyari B. Wamalwa J. Wabomba R. m. Nthumbi Department of Chemistry College of Biological & Physical Sciences University of Nairobi Nairobi Kenya Department of Chemistry University of Johannesburg Johannesburg South Africa

A study was done to evaluate the removal of a cationic dye from simulated waste water onto rice husks (RH). Spectroscopic methods such as FTIR and SEm/EDX were used for adsorbent characterization. Experimental dependency on solution pH, initial dye concentration, agitation speed, adsorbentparticle size, temperature of the solution and contact time was evaluated. The adsorption data was tested using both Langmuir and freundlich isotherms. The data fitted well into Langmuir isotherm model with a monolayer adsorption capacity of 6.5 mg/g. Further, the separation factor (RL) value was less than unity indicating a favorable adsorption process. Adsorption kinetics was determined using pseudo-first-order, pseudo-second-order and intra-particle diffusion models. The results showed that the adsorption of malachite green onto rice husks followed pseudo-second-order model with a determination coefficient of 0.986. This work has revealed that rice husks have a great potential to sequester cationic dyes from aqueous solutions and therefore it can be utilized to clean contaminated effluents.

关键词： Adsorption malachite Green Rice Husks Isotherm Cationic Dye