间歇吸附器内活性炭纤维吸附性能的研究—线性吸附系统有效扩…

测定了间歇吸附器内活性炭纤维吸附水中微量三氯甲烷的主体浓度变化曲线以及吸附等温平衡线，根据扩散模型的精确解与近似解，用误差等值图法估算了有效扩散系数以及液膜传质系数，在此基础上，对比了活性炭纤维与颗粒活性炭的传质特征，结果表明，本实验系统中传质过程接近于外扩散控制，近似解与精确解吻合较好；与颗粒活性炭相比，活性炭纤维具有良好的传质性能。     

间歇吸附器内活性炭纤维吸附性能的研究──线性吸附系统有效扩散系数的估算

测定了间歇吸附器内活性炭纤维吸附水中微量三氯甲烷的主体浓度变化曲线以及吸附等温平衡线，根据扩散模型的精确解与近似解，用误差等值图法估算了有效扩散系数以及液膜传质系数。在此基础上，对比了活性炭纤维与颗粒活性炭的传质特征。结果表明：本实验系统中传质过程接近于外扩散控制，近似解与精确解吻合较好；与颗粒活性炭相比，活性炭纤维具有良好的传质性能。     

活性炭纤维对水中镉离子的吸附研究

以活性炭纤维作为去除水中镉离子的吸附剂。考察了振荡时间、活性炭纤维用量、水样pH对吸附效果的影响。并通过等温吸附平衡实验作出了吸附等温线 ,采用有关的等温吸附模式对吸附平衡实验数据作了线性模拟 ,对吸附规律进行了探讨。结果表明 ,振荡时间、活性炭纤维用量、pH是影响镉离子在活性炭纤维上吸附效果的主要因素 ,吸附效率随着振荡时间的延长、活性炭纤维用量的增加、pH的增大而增大。吸附容量随活性炭纤维用量的增加而减小。镉离子在活性炭纤维上的吸附规律可用Langmuir模式和Freundlich模式很好地描述。吸附形式呈单分子层且容易进行。结果表明 ,活性炭纤维对水中镉离子的吸附特性良好 ,可作为去除水中离子态镉的优良吸附剂。     

活性炭纤维对水中镉离子的吸附研究

以活性炭纤维作为去除水中镉离子的吸附剂。考察了振荡时间、活笥炭纤维用量、水样ＰＨ对吸附效果的影响,并通过等温吸附平衡实验作出了吸附等温线,采用有关的等温吸附模式对吸附平衡实验数据作了线性模拟,对吸附规律进行了探讨。结果表明,振荡时间、活发现用量、ＰＨ是影响镉主子在活性炭纤维上吸附效果的主要因素,吸附效率随着振荡时间的延长、活性炭纤维用量的增加,ＰＨ的增大而增大。吸附容量随活性和量的而减小。镉离子在     

巯基中空纤维亲和膜Hg2+动态等温吸附方程的计算机模拟

在测定巯基中空纤维亲和膜对Hg ^2＋动态等温吸附方程的基础上,利用C＋＋语言编程,按Langmuir、Lang- muir-Freundlich和扩展的Langmuir 3个模型对吸附Hg ^2＋实验数据进行拟合,分别检验了实验数据的拟合程度.这3个模型对实验数据都拟合较好;相对其它两个模型,扩展Langmuir模型提供了最好的拟合,从而推断出巯基中空纤维亲和膜对Hg ^2＋的动态等温吸附是非完全的单分子层吸附.     

活性炭纤维填充床脱除水中苯和氯苯及其再生的研究

研究了活性炭纤维填充床脱除水中苯和氯苯的吸附性能，探讨其饱和吸附填充床的再生方法．结果表明：当平衡浓度变化范围为100～300mg／L时，活性炭纤维对水中苯和氯苯的吸附能力分别达280mg／g(吸附剂)和370mg／g(吸附剂)，吸附等温线符合Langmuir型；填充床的突破曲线和突破时间强烈依赖于实验条件；较高的进料浓度、以及较短的床层长度都将使填充床突破较快；用120℃的水蒸气再生被氯苯饱和的活性炭纤维填充床，再生效率达93％以上．在低Reynolds数下，轴向扩散对突破曲线影响最大.     

苯酚的吸附与扩散研究

首先确定了水溶液中苯酚在活性炭上的吸附等温式，然后根据平衡接近率与时间的关系，应用Ｐａｔｅｒｓｏｎ热传导近似公式，用计算机超越方程，得到了苯酚在活性炭粒内有有效扩散系数。     

嫩黄染料在活性炭纤维上的吸附研究

研究嫩黄染料水溶液于20℃及25℃在活性炭纤维上的吸附平衡关系.根据嫩黄染料在20℃和25℃的表观吸附量求出相应的真实吸附量:t=20℃时的真实吸附量为150 mg/g,t=25℃时的真实吸附量为144mg/g.嫩黄染料水溶液吸附平衡符合Freundlich吸附等温关系,拟合计算结果为:20℃时qe=105ρe0.203 51,25℃时qe=95ρe0.227 57.并研究嫩黄染料水溶液的初始浓度和活性炭纤维质量对间歇吸附动力学曲线的影响.最后对嫩黄染料水溶液在固定床上的吸附动力学特性进行研究.     

粉煤灰处理生活污水

以火电厂贮灰场粉煤灰为吸咐剂，以生活污水为吸附处理对象，通过间歇吸附实验研究了粉煤灰对生活污水中化学耗氧物质（ＣＯＤ）的吸附规律，并与活性炭的吸附性能进行了比较。结果表明，粉煤灰对生活污水中的ＣＯＤ有较强的吸附作用，当灰水比为１：１０时，粉煤灰和活性炭的平衡去除率分别为８６．０％和９５．１％。粉煤灰对ＣＯＤ的吸附行为符合氟兰德利希等温方程式。低ｐＨ值、高灰水比、粗粒径粉煤灰有利于ＣＯＤ的去除。     

活性炭纤维处理染料废水的实验研究

用活性炭纤维处理含有多种直接染料的模拟废水进行正交试验,分析了影响活性炭纤维处理染料废水的因素,初步确定了活性炭纤维处理直接染料废水的运行条件．通过对酸性铬蓝K的吸附实验,作出活性炭纤维对酸性染料的吸附等温线．实验结果表明,活性炭纤维对酸性染料的吸附符合弗兰德里希吸附．     

Biosorption of methylene blue by chemically modified cellulose waste

Citric acid modifi ed cellulose waste（CMCW） was prepared via esterifi cation and used as a low-cost biosorbent for the removal of methylene blue（MB） from aqueous solutions. The effects of biosorbent concentration, initial pH of MB solution, biosorption temperature, contact time, and initial MB concentration on the biosorption of MB were investigated using batch biosorption technique under static conditions. The experimental results showed that CMCW exhibited excellent biosorption characteristics for MB. The maximum biosorption capacity of MB was up to 214.5 mg/g at an adsorption temperature of 293 K. The removal rate of MB onto CMCW reached the maximum at pH〉4 and the biosorption reached an equilibrium at about 50 min. The kinetic data can be described well with the pseudo-second-order model and the isotherm data was found to fi t the Langmuir isotherm with a monolayer adsorption capacity of 211.42 mg/g. The biosorption appears to be controlled by chemisorption and may be involved in surface adsorption and pore diffusion during the whole biosorption process.     

Adsorption characteristics of carbon tetrachloride from aqueous solution onto polyacrylonitrile-based activated carbon fiber

The isotherm, mechanism and kinetics of carbon tetrachloride (CT) adsorption by polyacrylonitrile-based activated carbon fiber (PAN-ACF) were investigated in batch reactors and a continuous flow reactor, and the regeneration of PAN-ACF was also studied. Freundlich and Dubinin-Radushkevich (D-R) adsorption equations can well describe the adsorption isotherm. CT is mainly adsorbed on the exterior surface of PAN-ACF with low boundary layer effect and rate-controlling step of intra-particle diffusion. The adsorption dynamics in the batch reactor well fits with the pseudo-first-order model, and the breakthrough curves in the continuous flow reactor can be well described by the Yoon-Nelson model. The ACF can be recycled through thermal regeneration, whereas the adsorption capacity decreases from 7.87 to 4.98 mg/g after the fourth regeneration. 78%–94% of CT can be removed from the wastewater of a fluorine chemical plant on a pilot scale, which confirms the efficacy of ACF under industrial conditions. The results indicate that PAN-ACF is applicable to CT removal from wastewater.     

Kinetics and mechanism of the adsorption of methylene blue onto ACFs

The kinetics and mechanism of methylene blue (MB) adsorption onto activated carbon fibers (ACFs) have been studied.The effects of various experimental parameters, such as the initial MB concentration and the ACF mass, on the adsorption rate were investigated. Equilibrium data were fit well by a Freundlich isotherm equation. Adsorption measurements show that the process is very fast. The adsorption data were modeled using first- and second-order kinetic equations and intra-particle diffusion models. It was found that the first-order kinetic equation could best describe the adsorption kinetics. The adsorption process was found to be complex and controlled by both surface and pore diffusion with surface diffusion at the earlier stages, followed by pore diffusion at the later stages. The thermodynamic parameters △G0, △S0 and △H0, have been calculated. The thermodynamics of the MB-ACF system indicate that the adsorption process is spontaneous.     

改性MCM⁃41孔内水分子吸附扩散行为的模拟研究

通过构建多种官能团负载的MCM?41骨架模型，使用GCMC与MD模拟方法计算了水分子在不同亲疏水性质的MCM?41孔内的吸附及扩散性质。结果表明，MCM?41材料的水吸附等温线主要为Ⅱ型；负载到MCM?41孔表面的亲水官能团能够与水分子形成氢键，因此对水分子的相互作用力较疏水官能团高约114.27%；MCM?41孔内水分子的扩散能力与表面官能团的亲水性呈正相关，亲水表面的材料内水分子的扩散系数相较于疏水表面扩散系数高约58.82%；证明了亲水表面的MCM?41材料在含水环境中对孔内水分子的吸附扩散行为具有一定促进作用。     

Ammonia nitrogen removal from aqueous solution using zeolite modified by microwave-sodium acetate

The characteristics of the zeolite modified by microwave and sodium acetate and its sorption of ammonia-nitrogen from simulated water sample were investigated.The results show that the modified zeolite by microwave-sodium acetate(SMMZ)has a high sorption efficiency and removal performance.The ammonia-nitrogen removal rate of SMMZ reaches 92.90%.The surface of SMMZ becomes loose and some pores appear,the specific surface area,total pore volume and average pore diameter increase after modification.Compared to the natural zeolite,SMMZ has a more concentrated pore size distribution in the range of 0-10 nm.The cation exchange capacity(CEC)of SMMZ is higher than that of the natural zeolite.And the ammonia nitrogen removal rate is consistent with the change of CEC.The SMMZ possesses rapid sorption and slow balance characteristics and ammonia-nitrogen sorption is consistent with both Langmuir adsorption isotherm model and Freundlich adsorption isotherm model.The adsorption kinetics of ammonia-nitrogen follows the pseudo-second order kinetic model.     

Improved analytic methods for coal surface area and pore size distribution determination using 77 K nitrogen adsorption experiment

77 K nitrogen adsorption was the most widely used technique for determining surface area and pore size distribution of coal. Brunauer–Emmett–Teller (BET) and Barrett–Joyner–Halenda (BJH) model are commonly used analytic methods for adsorption/desorption isotherm. A Chinese anthracite coal is tested in this study using an improved experimental method and adsorption isotherm analyzed by three adsorption mechanisms at different relative pressure stages. The result shows that the micropore filling adsorption predominates at the relative pressure stage from 6.8E−7 to 9E−3. Theoretically, BET and BJH model are not appropriate for analyzing coal samples which contain micropores. Two new analytic procedures for coal surface area and pore size distribution calculation are developed in this work. The results show that BET model underestimates surface area, and micropores smaller than 1.751 nm account for 35.5% of the total pore volume and 74.2% of the total surface area. The investigation of surface area and pore size distribution by incorporating the influence of micropore is significant for understanding adsorption mechanism of methane and carbon dioxide in coal.     

热处理对多孔玻璃孔径的影响

采用Na2O-B2O3-SiO2系统制备基体玻璃.经分相和酸浸析等处理方法.制得多孔玻璃.采用氮吸附静态容量法,测得多孔玻璃的氮吸附等温线、比表面积和孔分布曲线.讨论分相时间和温度对多孔玻璃的孔径和孔隙率分布的影响.总结了多孔玻璃的孔径随着热处理的温度和时间的变化规律.     

Adsorption of K+ from an aqueous phase onto an activated carbon used as an electric double-layer capacitor electrode

The adsorption capacity and absorption rate for electrolyte onto activated carbon are important parameters used to characterize activated carbon electric double-layer capacitor electrodes. In this paper the pore structure of typical commercial activated carbons, and various Mn-doped activated carbons prepared on a laboratory scale, are described. The pore structure was characterized by N2 adsorption/desorption isotherms. Isotherms for K+ adsorption onto these activated carbons from the aqueous phase were also obtained. The experimental, equilibrium K+ adsorption data were fitted to the Langmuir, Freundlich or Temkin equations. Adsorption of K+ onto the activated carbons was measured and plotted as a function of time. The adsorption kinetic data were modeled by either pseudo-first or pseudo-second order equations. The Elvoich equation, a liquid film diffusion and an intra-particle diffusion model were used to fit the kinetic data. The results indicate that the adsorption of K+ onto activated carbon is influenced by many factors including pore size distribution, specific surface area and the surface chemistry of the activated carbons. The Temkin equation best describes the equilibrium adsorption data. The pseudo-second order model exactly describes the whole adsorption process, which is controlled by both liquid film and intra-particle diffusion.     

再生混凝土中的水分扩散机理与模型

对再生混凝土处在干燥环境中的水分扩散机理进行了研究 ,并建立了相应的水分扩散模型。为了确定水分扩散的有关参数 ,对再生混凝土的水分扩散实验结果采取了回归分析方法 ,实验结果与诸多文献报道具有很好的一致性。结果显示混凝土内部孔隙湿度 R随环境相对湿度 H的增加而增加 ,随环境温度 T的增加而减少 ;在外部环境相同的条件下 ,再生混凝土内部孔隙湿度 R随混凝土 W/ C的增加而增加 ;再生混凝土中的水分扩散系数 Dwd较普通混凝土的水分扩散系数大     

金属离子-腐植酸复合凝胶的制备及其对氟吸附研究

为提高水中F-的吸附去除效率,以腐植酸（HA）为原料,用铝盐和钙盐通过凝胶聚合法对其改性,制备了金属离子-腐植酸复合凝胶吸附剂（标记为SPMA）.用SEM、XRD、IR 及N2吸附–脱附实验表征吸附剂的结构和形貌,通过静态吸附实验探讨了SPMA对水中F-的吸附性能.研究结果表明,SPMA对水中F-的等温吸附结果与Langmuir方程能较好地拟合,其饱和吸附容量为147.28mg/g;吸附过程遵循准2级动力学方程,其速率控制步骤包括边界层扩散和内部扩散两个过程;在pH值为5-9时SPMA对水中F-具有较高的吸附率,SO42-, NO3- 和 Cl- 对 F- 的吸附率没有影响,在相同浓度的HCO3-或PO43-存在下,SPMA对 F-的吸附率仍达到80%,表现出了一定的抗干扰能力.