| The season amino as functional group was introduced onto the sawdust cellulose through by 3-chlorine-2-hydroxypropyl chloride (CTA) as etherizing agent to get a series of hydrogen bonding polymeric adsorbents.The newly sawdust cellulose were characterized by IR spectrometer and surface area measurement instrument and scanning electron microscope. The results indicated that after the treatmen, the physical structure and morphology had certain changes, such as, removed some of the impurities attached to the fiber surface, enhanced the degree of ordering structure of sawdust cellulose, formed along the longitudinal cellulose significantly within the hollow shape and decreased the surface area. In addition, the chemical structure of sawdust cellulose was no significant changes, indicating modification did not cause major structural damage to sawdust cellulose. The modified sawdust cellulose appeared a characteristic absorption peak at 1380 cm-1 in infra-red spectra, charactering for the CN bond vibration, indicating functional group has been introduced into skeleton.Accoding to the study on the absorption of phenol and 2,4-DCP in aqueous solutions, the adsorption capacity of modified sawdust cellulose had significant increase for phenol and 2,4-DCP, which could reach 2.6mg·g-1 and 0.681 mg·g-1 at the temperature of 293K, Co dosage of 20 mg·L-1. The effect of adsorptiont was not only due to quaternary ammonium salt groups on the surface and skeleton of modified sawdust cellulose result of joint action, but to closely relating to the physical and chemical properties of phonel and 2,4-DCP. The adsoption isotherm curves of phonel and 2,4-DCP on modfied sawdust cellulose can be described by Langmuir and Freundlich equation at the same time, but the Freundlich equation had better correlation, which showed that the adsorption of them were combining effect of monolayer adsorption with multilayer adsorption.The study had shown that phenol was more easily adsorbed by modified sawdust cellulose, and the force of reverse electric ions couldn't be the only factor in aqueous solution, resin surface area and pore structure were also important to the adsorption. In other words, the ablilities of adsorption were caused by both tertiary amine group and resin skeleton.The value of pH had a greater impact on the adsorption percentage. The optimal pH value for phenol and 2,4-DCP were 8.0 and 6.0 which also proved that the adsorption of sawdust cellulose adsorbent to phenolic compounds was due to the attraction of opposite charge. The adsorption enthalpy of phenol and 2,4-DCP were negative and their absolute values were less than 40 kJ·mol-1. These datas of adsorption thermodynamics indicated the adsorption process was exothermic and conformed to isothermal line. The adsorption reactions were spontaneous exothermic process which reduced the degree of confusion and enhanced the ordering of entire aqueous solution.The data of adsorption kinetics showed that the adsorption of modified sawdust cellulose from aqueous solutions were in good agreement with the pseudo-second rate equation. The activation energy and the adsorption heat calculated was relatively low, implying the adsorption of 2,4-DCP on sawdust cellulose was a typical physical adsorption process. The adsorptive performance of binary solutes including tannin and 2,4-DCP onto modified sawdust cellulose from simultaneous competing adsorptive environment were investigated and the adsorptive selectivity was simultaneously discussed which indicated that the sawdust was greater suitable to treating phenolic compounds with small molecular weight.New polymeric adsorbents oxidized by oxydol (XR-01) or nitric acid (XR-02) group from hypercrosslinked polystyrene-divinylbenzene copolymer were prepared in water. The total content of acidic groups oxidized by oxydol (XR-01) were much more than that oxidized by nitric acid (XR-02), and their chemisoption would be in existence in the adsorption process of 2,4-dichlorophenol in aqueous solutions. The adsorption datas obtained from isotherm experiments could be well described using Freundlich and Langmuir adsorption isotherm model, respectively.It was founded that the adsorption rate could reach about 97% when the practical treatments were studied by using modified sawdust cellulose to dispose of chemical wastewater containing 2,4-DCP. By using extraction-adsorption combined process to deeply treat the wastewater containing fluorobenzene, the recovery rate of phenol was greater than 93.4%. The economic benefits will be approximately 147,300 yuan based on 7500 tons of fluorobenzene wastewater per year and the process can reduce the emissions of phenol by 22.5 tons to the environment which can realize good environmental and economic benefits.
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