生物质海绵基活性炭纤维吸附苯酚性能研究

用生物质海绵基活性炭纤维(LSF-ACF)吸附模拟废水中的苯酚,考察了温度、pH、投加量以及苯酚初始浓度对吸附效果的影响,研究了吸附平衡模型和吸附动力学模型。结果表明:酸性或弱碱性(pH≤9)条件下有利于LSF-ACF吸附苯酚;当投加量8 g/L时,LSF-ACF对苯酚的去除率趋于最大值(96.5%),达到动态平衡;由Langmuir和Freundlich吸附等温模型拟合出来的吸附曲线R2都达到0.95以上;LSF-ACF对苯酚溶液的吸附符合拟二级反应动力学,R2为0.999 8。     

强碱性苯乙烯系树脂对水中苯酚的吸附研究

以201×7强碱性苯乙烯系阴离子交换树脂对水中苯酚进行吸附性能研究。详细研究了吸附体系中溶液的pH值、苯酚的起始浓度、树脂的投加量对吸附的影响,并将平衡数据用Langmuir和Freundlich方程进行对比分析。结果表明,吸附量随pH增大而增大,pH≥7时吸附量趋于恒定达到最大值;吸附量随着苯酚起始浓度的增大而降低,苯酚去除率随着树脂投加量的增加而增大;吸附过程更符合Langmuir模型。     

强碱性苯乙烯系树脂对水中笨酚的吸附研究

以201×7强碱性苯乙烯系阴离子交换树脂对水中苯酚进行吸附性能研究.详细研究了吸附体系中溶液的pH值、苯酚的起始浓度、树脂的投加量对吸附的影响,并将平衡数据用Langmuir和Freundlich方程进行对比分析.结果表明,吸附量随pH增大而增大,pH≥7时吸附量趋于恒定达到最大值;吸附量随着苯酚起始浓度的增大而降低,苯酚去除率随着树脂投加量的增加而增大;吸附过程更符合Langmuir模型.     

膨润土负载壳聚糖吸附剂对苯酚的吸附性能研究

将壳聚糖与膨润土复合制得一种固体吸附剂(CCB),并用于水溶液中苯酚的吸附。详细研究了吸附体系中溶液pH值、苯酚起始浓度对吸附的影响,将吸附平衡数据用Langmuir和Freundlich方程进行对比分析。结果表明:温度为25℃的条件下,溶液pH值为4.0时,吸附容量最大,达到63.69 mg/g;吸附量随苯酚起始浓度的增大而增大,吸附过程符合Langmuir和Freundlich模型,其中Langmuir模型更为适合。     

活性炭纤维对Cu2+的吸附性能研究

活性炭纤维(ACF)作为一种新型活性炭吸附材料已引起了化学家们的极大关注。孔结构分析表明:活性炭纤维的孔径分布窄,孔径比较均匀。本文以活性炭纤维作为去除水中重金属离子Cu2+的吸附剂,吸附实验表明,活性炭纤维对Cu2+的最大吸附量为148.50mg.g-1,吸附平衡时间短,当接触时间为50min时,即可达到吸附平衡,吸附过程符合Langmuir和Freundlich模型。动态吸附结果表明,活性炭纤维对Cu2+的吸附量随着流速的增加而降低。     

通过活性炭吸附法处理煤化工废水中苯酚的探究

以活性炭为吸附剂吸附煤化工废水中的苯酚,采用4-氨基抗吡啶吸光度法测定吸附后的废水中的苯酚含量。通过研究活性炭吸附时间、苯酚初始浓度、活性炭投加量、活性炭粒径、溶液pH值等因素对对苯酚去除率的影响,最终确定当酚含量和活性炭中的活性炭量为1:1000时,吸附在900分钟内达到吸附平衡。用200目活性炭在最佳苯酚初始浓度、溶液pH为弱酸性的条件下,静态吸附900 min,于502 nm波长处测定,苯酚的去除率达到97.13%。     

活性炭纤维填充床脱除水中苯酚及填充床的再生

采用活性炭纤维吸附法净化水中微量的苯酚。在25℃、30℃和35℃下,实验测定活性炭纤维吸附苯酚的吸附平衡等温线,该吸附等温线符合Langmuir型,最大饱和吸附容量达0．26kg(苯酚)／kg(活性炭纤维)在25℃下;0．25kg(苯酚)／kg(活性炭纤维)在30℃下;0．239kg(苯酚)／kg(活性炭纤维)在35℃下。水溶液的pH值将影响吸附容量,在碱性条件下吸附容量显著下降,这将有利于吸附剂的再生。苯酚在活性炭纤维填充床的穿透曲线被测量,在5％突破点处的动态吸附容量为0．14kg(苯酚)／kg(活性炭纤维)在25℃下。采用40℃、5％NaOH溶液再生被苯酚饱和的活性炭纤维填充床,再生后吸附效率达90％以上。     

活性炭纤维处理含氰废水的研究

本文采用活性炭纤维处理含氰废水,同时利用NaOH再生吸附饱和的活性炭纤维,以达到资源回收利用的目的.通过静态吸附研究,测定了吸附等温线,并且研究了pH值、吸附平衡时间对处理效果的影响.结果表明,活性炭纤维对CN-的吸附容量为2.2~3.6mg·g-1,吸附平衡关系服从Langmuir型吸附等温线;溶液pH值在6~10范围内,吸附效率较好;吸附平衡时间存在最佳值,最佳吸附时间为6h.吸附饱和的活性炭纤维用10%的NaOH溶液再生,重复使用3次,吸附效率无明显变化.     

类人胶原蛋白Ⅱ的离子交换吸附平衡研究

研究重组类人胶原蛋白Ⅱ(RHLCⅡ)在CM52树脂上的吸附平衡,考察pH值、NaCl浓度及温度对吸附平衡的影响。结果表明:当4.0pH≤5.0时,随着pH值增大,吸附容量减小,解离系数Kd增大;当3.0≤pH4.0时,随着pH值增大,吸附容量增大,解离系数Kd减小;随着NaCl浓度增大,吸附容量减小,解离系数Kd增大;温度对Langmuir方程参数的影响较小,温度每升高10℃,吸附容量增加3%左右,解离系数Kd的变化不显著。RHLCⅡ在CM52树脂上的吸附基本符合Langmuir方程,为离子交换法规模制备RHLCⅡ提供了理论依据。     

果壳活性炭对废水中苯酚的吸附特性

研究了果壳活性炭对废水中苯酚的吸附特性,考察了接触时间、温度、pH值对吸附效果的影响,绘制了吸附等温线和动力学曲线。试验结果表明:果壳活性炭对苯酚的吸附约6 h即已趋于平衡,去除率达到96.63%。该吸附过程受温度影响不显著;溶液pH值对吸附量影响较大,酸性至中性条件下苯酚的吸附效果更佳。在给定吸附剂浓度条件下,Langmuir和Freundlich吸附等温式均能较好拟合平衡吸附数据,动力学试验数据则与Lagergren准二级动力学方程的拟合度最佳。     

农业废弃物香芋柄对含Mn2+废水的吸附

以废弃香芋柄作为新型生物吸附剂,通过静态吸附实验,研究了pH、温度、吸附时间、Mn2+初始浓度等因素对香芋柄吸附Mn2+的影响,分析了吸附过程的热力学、动力学和等温吸附规律. 结果表明,溶液初始pH=4,香芋柄用量6 g/L,30℃下吸附60 min,溶液中Mn2+吸附去除率达90.79%以上,吸附容量高达18.16 mg/g. 应用Langmuir和Freundlich模型描述香芋柄对Mn2+的吸附过程,结果显示Freundlich吸附等温线拟合效果更好. 吸附动力学实验数据符合准二级动力学模型. 计算得到热力学参数DG<0, DH>0, DS>0,表明该吸附过程是自发和吸热的过程.     

Copper biosorption by Myriophyllum spicatum: Effects of temperature and pH

Using submerged aquatic plants is a cheap and clean technique to remediate heavy metal water pollution at low concentrations. Biosorption of Cu(II) ions by fresh tissues of Myriophyllum spicatum, a submerged aquatic plant, was characterized in an artificial solution system under different values of contact time, temperature and pH in this paper. Cu(II) biosorption was fast and equilibrium was attained within 20 min. The equilibrium biosorption data were analyzed using three widely applied isotherm models: Langmuir, Freundlich and Redlich-Peterson isotherm. Langmuir isotherm parameters obtained from the three Langmuir linear equations by using linear method were dissimilar, except when the non-linear method was used. Best fits were yielded with Langmuir and Redlich-Peterson isotherms (R²=0.961–0.992 and 0.990–0.998, respectively). The saturated monolayer biosorption capacity of M. spicatum for Cu(II) at 298 K was calculated to be 0.19 mmol/g. The biosorption capacity of M. spicatum for Cu(II) increased with increasing pH, and the resulting isotherms were well described by Langmuir and extended Langmuir models (R²=0.931–0.993 and 0.961, respectively). The comparison of calculated q _e and experimental q _e values showed that the extended Langmuir model had a better simulation for Cu(II) biosorption by M. spicatum than the Langmuir isotherm model. FT-IR was used to characterize the interaction between M. spicatum and Cu(II), with the results indicating that carboxyl groups played an important role in Cu(II) binding.     

Multifunctional Adsorbent: Oleophobic Latex Sponge for Removing Dyes and Cu2+ from Sewage Waste

A latex sponge is modified by chitosan, tannic acid, and silane coupling agent KH550 to prepare an oleophobic sponge adsorbent, which can adsorb different kinds of charged dyes and Cu²⁺. The static adsorption capacity of the latex sponge before and after modification to methyl orange (MO) (negative charge), rhodamine B (RB) (neutral), methylene blue (MB) (positive charge), and Cu²⁺ under different initial concentration, pH, and reaction temperature are investigated, and simulations of adsorption kinetics and isotherms are performed. The modified latex sponge improves the overall adsorption capacity along with the initial concentration and increases reaction temperature. The adsorption capacity of the adsorbent expands; when the pH is low, it is beneficial to adsorb MO and RB, and when the pH is high, it is favorable for the adsorption of MB and Cu²⁺. Adsorption kinetics and isotherm data show that the isotherm dates of pure latex sponge conform to the Langmuir isotherm model, while the isotherm dates of modified latex sponge conform to the Freundich isotherm model; however both of them are more fitted with the pseudo-second-order adsorption model, and the chemical adsorption is the main one.     

H-103树脂处理含酚废水的实验研究

研究了H-103大孔吸附树脂对600~1000 mg/L苯酚水溶液中酚的吸附,考察了初始酚浓度、溶液pH值及温度对吸附性能的影响. 结果表明,在20 min内吸附达到平衡,吸附动力学可用拟二级动力学模型描述. 苯酚在大孔树脂上的吸附等温线很好地符合Langmuir吸附等温方程,在25℃下其饱和吸附量和Langmuir常数分别为86.00 mg/g和0.2719 L/mg.     

EFFECT OF TEMPERATURE ON THE ADSORPTION OF METHYLENE BLUE DYE ONTO SULFURIC ACID–TREATED ORANGE PEEL

The present study explains the preparation and application of sulfuric acid–treated orange peel (STOP) as a new low-cost adsorbent in the removal of methylene blue (MB) dye from its aqueous solution. The effects of temperature on the operating parameters such as solution pH, adsorbent dose, initial MB dye concentration, and contact time were investigated for the removal of MB dye using STOP. The maximum adsorption of MB dye onto STOP took place in the following experimental conditions: pH of 8.0, adsorbent dose of 0.4 g, contact time of 45 min, and temperature of 30°C. The adsorption equilibrium data were tested by applying both the Langmuir and Freundlich isotherm models. It is observed that the Freundlich isotherm model fitted better than the Langmuir isotherm model, indicating multilayer adsorption, at all studied temperatures. The adsorption kinetic results showed that the pseudo-second-order model was more suitable to explain the adsorption of MB dye onto STOP. The adsorption mechanism results showed that the adsorption process was controlled by both the internal and external diffusion of MB dye molecules. The values of free energy change (ΔG ^o) and enthalpy change (ΔH ^o) indicated the spontaneous, feasible, and exothermic nature of the adsorption process. The maximum monolayer adsorption capacity of STOP was also compared with other low-cost adsorbents, and it was found that STOP was a better adsorbent for MB dye removal.     

Adsorption of trivalent chromium from aqueous solutions onto activated carbon

The adsorption of chromium (III) onto activated carbon was investigated as a possible alternative method for its removal from aqueous solutions. The adsorption data were obtained in a batch adsorber and fitted the Langmuir adsorption isotherm well. The effect of pH on the adsorption isotherm was investigated at pH values of 2, 4, 5 and 6. It was found that at pH values below 2 the Cr(III) was not adsorbed and at pH values above 6.4 the Cr(III) was precipitated as Cr(OH)₃. Maximum adsorption occurred at pH 5. The pH plays a very important role in the adsorption of Cr(III) since Cr(III) can form different complexes in aqueous solutions. The adsorption capacity was increased by about 20% as the temperature was raised from 25 to 40°C. It was concluded that Cr(III) is adsorbed to an appreciable extent on activated carbon and that the adsorption is highly dependent upon pH.     

Adsorption of zinc onto anionic ion-exchange resin from cyanide barren solution☆

Removal of zinc from cyanide barren solution is obligatory for its reuse in leach process. Batch experiments were carried out to evaluate the adsorption capacity of resins under different experimental conditions, including con-centration, resin amount, initial pH, contact time and temperature. More than 99%of adsorption was achieved under the optimal condition. High adsorption rates on the resin were observed at the beginning and plateau values were obtalned in 60 min. The thermodynamic parameters (free energy changeΔG, enthalpy changeΔS and entropy changeΔH) for the adsorption were evaluated. The adsorption kinetic mechanism was studied with four models. The experimental results show that the adsorption follows the Langmuir isotherm and the kinetics follows the pseudo-second-order model.     

Nickel and cobalt sorption on anaerobic granular sludges: kinetic and equilibrium studies

The kinetics and equilibria of sorption of the divalent metal ions cobalt and nickel onto anaerobic granular sludge are described. Single component and binary equimolar systems were studied at different pH values (pH 6, 7 and 8). The kinetic modelling of metal sorption by anaerobic granular sludge has been carried out using Lagergren equations. On fitting the experimental kinetic data both in first‐ and pseudo‐second‐order equations, the regression analysis of a pseudo‐second‐order equation gave a higher r² value, indicating that both external mass transfer and intra‐particle diffusion are involved in the sorption process. The experimental isotherm data were analysed using the Langmuir, Freundlich and Redlich–Peterson equations. The Redlich isotherm, a combination of the Langmuir and Freundlich equations, was found to have the highest regression correlation coefficients at pH 7. At pH 8, the Langmuir mechanism dominated for cobalt and nickel adsorption. In contrast, at pH 6, the Freundlich equation gave a better correlation coefficient which suggests a more heterogeneous adsorption at that pH. The maximal adsorption capacity of the granular sludge, as determined by the Langmuir equation, for cobalt or nickel in single systems (8.92 mg g^?1 Co TSS; 9.41 mg g^?1 Ni TSS, pH 7) compared with binary systems (8.06 mg g^?1 Co TSS; 8.43 mg g^?1 Ni TSS, pH 7) showed no great difference in the accumulation of these metals onto granular sludge. Copyright © 2004 Society of Chemical Industry     

Removal of Acid Violet 17 from Aqueous Solutions by Adsorption onto Activated Carbon Prepared from Pistachio Nut Shell

Adsorbents prepared from pistachio nut shell, an agricultural waste biomass, were successfully used to remove Acid Violet 17 from an aqueous solution. The activated carbons PNS1, PNS2, and PNS3 were characterized by scanning electron microscope (SEM), Fourier Transform – Infra Red spectroscopy (FTIR) and (BET). The effect of pH, adsorbent dosage, and temperature on dye removal was studied. Maximum color removal was observed at pH 2. The adsorption increased with the increase in adsorbent dosage. As the adsorption capacity increased with the increase in temperature, the process was concluded to be endothermic. The experimental data were analyzed by the Langmuir and Freundlich isotherm models of adsorption. Equilibrium data fitted well with the Langmuir model. The rates of adsorption confirmed the pseudo-second order kinetics with good correlation values. The results indicated that the activated carbon prepared from pistachio nut shell can be effectively used for the removal of Acid Violet 17 from aqueous solution.     

Study on adsorption characteristic of macroporous resin to phenol in wastewater

The removal of phenol from solution was investigated using macroporous resin. The effects of initial concentration, pH, and temperature on phenol removal were studied. The experimental results indicated that the adsorption capacity reached equilibrium state within 20 min and adsorption followed pseudo‐second‐order kinetic model. Langmuir isotherm model could be better to describe the isothermal adsorption of phenol, the maximum adsorption capacity (Q_m) and Langmuir constant (K_L) were 103.64 mg/g and 0.2719. Macroporous resin after reached to saturation has a high desorption percentage, indicating that H‐103 is an excellent reusing adsorption material. It provided theoretical references for practical application in phenolic wastewater treatment.