The adsorption of cationic polymer, i.e., epicholorohydrin-dimethylamine polyamine (EPI-DMA), on bentonite particles wasinvestigated under various conditions of bulk polymer concentration, pH, inorganic salts, and temperature. The resulting highadsorption rate and alkaline solution (pH=7–11) effect indicated a strong electrostatic interaction between the clay particles and EPIDMAmolecules.Addition of salt can also influence the adsorption of EPI-DMA onto bentonite by affecting the clay particle sizes, thepolymer zeta potential and etc. The Freundlich and Langmuir isotherm models were employed and fit the experimental data well in thelow EPI-DMA concentration range 0.5–5.0 mg L−1. The enthalpy implied by the temperature dependence of adsorption of EPI-DMAon bentonite is 7.93 kJ mol−1, suggesting that neither coordination exchange nor chemical bond forces exit in this system. In addition,at high temperatures, larger amounts of EPI-DMAwere adsorbed by bentonite, which indicated that increased entropy in the dissolvedEPI-DMA molecules contributes to adsorption. The X-ray diffraction (XRD) analysis showed that besides the EPI-DMA moleculesintercalated between the layers of bentonite, excess polymer molecules were adsorbed onto polymer loops protruding from the surfaceof the complex. The TGA and corresponding DSC plots demonstrated that the EPI-DMA polymer had intercalated into the clay layersand thus the EPI-DMA/bentonite was more hydrophobic than natural bentonite. With the addition of EPI-DMA polymer, thenegatively charged clay particles increased to a net positive charge and the capacity for dye removal also went up with increasingpolymer contents in EPI-DMA/bentonite complexes.

The characterization of polyepicholorohydrin-dimethylamine/bentonite and the kinetics of adsorption of four disperse dyes, namely, DisperseYellow Brown S-2RFL (DYB S-2RFL), Disperse Red S-R (DR S-R), Disperse Blue SBL (DB SBL) and Disperse Yellow (DY SE-6GFL) ontoorganophilic bentonite (polyepicholorohydrin-dimethylamine/bentonite) have been studied at various solution concentrations and temperatures.The adsorption kineticswas studied in terms of a two-step first-order kinetic rate equation and intra-particle diffusion model. The adsorption processhas been found to followwith two different rate constants (k1 and k2) for two-step first-order kinetic rate equation and also two different intra-particlediffusion rate constants (kint1 and kint2) for intra-particle diffusion model. For both the kinetic steps, the energies of activation of adsorption (Ea1 andEa2) and other thermodynamic parameters (_H∗1 and _H∗2, _S∗1 and _S∗2, _G∗1 and _G∗2) have been calculated using Arrhenius’s and Eyring’sequation, respectively. It has been found that for both the adsorption kinetic steps, Ea1 and Ea2 are corresponding to the values of k1 and k2 and_H∗1 < −Tav _S∗1 , _H∗2 < −Tav _S∗2 and _G* > 0, which means that the influence of entropy is more remarkable than enthalpy in activationreaction and the adsorption process is not spontaneous.

Polyamine flocculants were synthesized by the polycondensation of dimethylamine and epichlorohydrin, in which organic amines, e.g. 1,2-diaminoethane, were used as modifying agents. Different products were obtained by varying the reaction parameters, such as the molar ratio ofepichlorohydrin to dimethylamine, the amount of 1,2-diaminoethane and reaction temperature. The polyamine flocculants were characterized bytransmission electron microscope (TEM). Their flocculation performance was evaluated with simulated dye liquor and actual printing and dyeingwastewater. The behavior of the flocculantswas compared with that of inorganic coagulant, polyaluminum chloride (PAC). The experimental resultsshow that polyamine with the highest viscosity and cationicity could be prepared under following conditions: an epichlorohydrin to dimethylaminemolar ratio of 1.5, a reaction temperature of 70 ◦C, a 3% content of 1,2-diaminoethane in the total reaction monomers and a reaction time of 7 h.Polyamine polymers can, as flocculants for treating simulated and actual dye wastewater, remove color and COD efficiently. The rate of colorremoval from reactive red liquor, reactive blue liquor and reductive yellow liquor reached as high as 96%, 97% and 96%, respectively. The highestefficiency of color removal and COD removal from polyamine for treating dye wastewater was 90% and 89%, respectively.

Fly ash modification by polydimethydiallylammonium chloride (PDMDAAC) in laboratory scale was explored in this work and the adsorptionperformance of modified fly ash and its application in dyeing wastewater treatment were also studied.The key factors (concentration and temperature) for PDMDAAC to affect the adsorption properties of fly ash (FA) were revealed using theorthogonal test with four factors. The results indicated that the adsorption magnitude of fly ash to PDMDAAC increased due to its favorablespecific surface causing the change of the surface charge nature. Hence, adsorption performance of modified fly ash on organic molecules and itsion exchange capacity are strengthened. The maximum color removal efficiency was obtained as 88.2% by modified fly ash with 2.0 g/100mLdosage in dyeing wastewater, which is much higher than 12.5% color removal efficiency by raw fly ash with the same dosage. And, the usedmodified fly ash could be used for cement production as additive agent. The intensity of cement produced with 15% the modified fly ash in weightreached the Chinese Cement Standard (GB/T17671-1999), blazing a promising novel way in fly ash utilization.

In this study, the cationic polyelectrolyte polyepicholorohydrin-dimethylamine (EPI-DMA) was intercalated into bentonite using ultrasonic.The structure of EPI-DMA/bentonite and its adsorption of Reactive Blue K-GL (RB K-GL) dye were investigated. Compared with raw bentonite,the EPI-DMA/bentonite had larger interlayer spacing and was more hydrophobic, providing with better surface properties for adsorption. Theadsorption of RB K-GL on EPI-DMA/bentonite was described by the adsorption models of Langmuir, Freundlich and Dubinin–Radushkevic. Theadsorption kinetics was analyzed using pseudo-first- and second-order kinetic models and intraparticle diffusion model. Results showed that boththe intraparticle diffusion and first-order adsorption occur in the initial period of adsorption, and that pseudo-second-order kinetic model was moresuitable for describing the whole adsorption process. The reaction rates were also calculated. The changes of free energy, enthalpy and entropy ofadsorption were evaluated for the adsorption of RB K-GL onto EPI-DMA/bentonite, suggesting that the adsorption process was spontaneous andexothermic.

以阳离子聚合物聚环氧氯丙烷二甲胺（EPI−DMA）为纳米复合材料插层剂，对膨润土进行改性，系统考察了聚环氧氯丙烷二甲胺在膨润土纳米层间插层过程中反应体系的聚合物用量、反应时间、温度、pH 值等工艺条件对插层效果的影响，并通过比表面积测定、Zeta 电位测定、X 射线衍射和透射电镜分析，对插层复合材料的结构和性能进行了研究，在此基础上初步探讨了其脱色性能。 结果表明，最佳制备工艺为EPI−DMA 的加入浓度7.0%，反应时间2.0h，温度75℃，体系pH 值7.0。 经聚环氧氯丙烷二甲胺插层复合后的膨润土比表面积增大，表面电性由负值变为正值，层间距、层间缔合结构和聚集程度增加，对红色染料废水具有较强的脱色效果。

研究了阳离子膨润土（EPI-DM/Bt，PD/Bt，CTMAB/Bt）对分散染料（分散黄棕S-2RFL，分散大红S-R，分散蓝SBL，分散黄SE-6GFL）的吸附动力学行为结果表明，阳离子膨润土对分散染料的吸附过程符合二阶段吸附速率方程，各阶段具有不同的吸附动力学常数（k1，k2）以及吸附活化能（Ea1，Ea2）、活化焓（△H1*，△H2*）和活化熵（△S1*，△S2*）；在阳离子膨润土对分散染料的吸附过程中，k1随着阳离子插层剂烷烃链的增加而增大，表明较大的晶片层司距，疏水的层司域和表面正电荷增加均有利于吸附速率增大；对于两个吸附动力学阶段，△H 1*<Tav△S1*，△H2*<-Tav△S2*和△G*>0表明整个吸附过程活化熵的影响大于活化焓

采用共聚与复合两种制备工艺，分别制备出具有不同碱化度（B）和不同Al/Si摩尔比系列的商用聚硅氯化铝（PASiC）混凝剂，并分别采用颗粒粒径测定方法和流动电流（SC）测定技术研究比较了PASiC和聚合氯化铝（PAC）混凝剂的颗粒大小电动特性和凝聚絮凝动态过程。结果表明，Al/Si摩尔比B值和制备工艺影响PASiC的聚合和带电特性。Al/Si摩尔比越小和B值越大，PASiC的颗粒就越大；在相同的B值下，PASiC较PAC具有更大的颗粒粒径。PASiC的电中和能力较PAC有所下降，且Al/Si摩尔比越小，PASiC的电中和能力下降越多；与PAC相比，PASiC具有更快的凝聚絮凝速度和形成更大的絮体；且Al/Si摩尔比越小，PASiC形成的絮体就越大。

Adsorption thermodynamic characteristic and kinetics of dissolved chromium from aqueous solutionsonto humic acids (HAs) were studied. The results showed that the Freundlich isotherm model describedthe equilibrium data well. The negative _G◦ confirmed the spontaneity of adsorption process. The positive_H◦ and _S◦ proved the endothermic nature and irreversibility of the sorption. Furthermore, theadsorption process followed the pseudo-second-order equation. With increasing initial concentration ofCr(VI), the adsorption rate constant decreased while the maximum adsorption capacity increased.

Cationic copolymer acrylamide-dimethyldiallylammonium chloride[P(AM/DMDAAC)] wassynthesized from acrylamide (AM) and dimethyldiallylammonium chloride (DMDAAC) by dispersionpolymerization. The structures of polymers synthesized in different systems of dispersion were determinedwith infrared spectroscopy. The results showed that ethanol-H2 O was the best system of dispersion. Thecharacteristics of PDMDAAC-AM were studied by means of various instrumental analysis techniques，including transmission electron microscope(TEM)and Zetasizer 3000HSA. The results showed that theparticle size of cationic PDMDAAC-AM synthesized in the ethanol-H2 O system of dispersion was withinthe range of nanometer，and the dispersion polymerization in the emulsion state was helpful to dissipationof rea ction heat