| In the 21 st century, one of the most important problems facing human beings is environment problem. The environmental protection has become the topics actively researched by many scientific researchers. Organic pollutants, especially poisonous organic pollutants, has been seriously harmed the health of ecosystems and the sustainable development of human society. The organic compounds containing in the wastewaters are difficult to be removed by biological treatment, because they are difficult to biodegrade. The usual physico-chemical or chemical treatment methods are cost, complicate and difficult to operation. Adsorption is a well-established technique for treating industrial effluents.This method is convenient, efficient and low cost, so attract widespread attention and study.In the first section, we summarized the methods for the treatment of organic compound, the basic knowledge of adsorption, the types of adsorbent and their application.Molecular imprinting technology which arises from molecular recognition is now a well established technique for developing artificial receptors possessing strong affinity for specific target molecules. In the presence of a template, monomers are arranged and co-polymerized to form a cross linked polymer. After removal of the template, a cavity complementary with the template in shape, size, and interaction is left. Based on a sol-gel procedure, a molecularly imprinted polymer (MIP) for 2, 4-dichlorophenoxyacetic acid (2,4-D) was synthesized, using tetraethoxysilane (TEOS), phenyltrimethoxysilane (PTMOS), aminopropyltriethoxysilane (APTES) as monomers. Both PTMOS and APTES were involved in the gelation process in addition to immobilize the template molecule 2,4-D. It is believed that PTMOS interacts with the template 2,4-D through hydrophobility andπ-πstaking, but APTES interacts with 2,4-D through electrostatic interaction and hydrogen bond. In addition to the amount of the template, some factors in the sol-gel process: TEOS/APTES/PTMOS molar ratio, H2O/Si molar ratio, CH3CH2OH/Si molar ratio, etc. were investigated in detail with the optimum conditions for the preparation of the MIPs being 20:1.5:1 (TEOS:APTES:PTMOS), ca.4 (H2O/Si), ca.4 (CH3CH2OH/Si), respectively. Effects of various parameters involved in the adsorption process of 2, 4-D on MIP such as incubation time, pH, ions strength, etc. were also evaluated. It is found that the adsorption attained equilibrium within 3 h, the optimum pH for adsorption was about 7, and adsorption capacities decreased with the increase of ions strength and the adsorption obeyed Langmuir and Freundlich models. Test results also demonstrated that the present MIP for 2,4-D had large adsorption capacity (the maximum adsorption concluded from Langmuir model reached 243.3 mg/g) and good selectivity.Congo red is anion state in general waste water, and adsorption capacity on the zeolite is very small. Surfactant modified zeolite can increase the absorption capacity. In the third chapter, hexadecyl trimethyl ammonium Bromide-modified zeolite was prepared and used as an adsorbent for Congo red in aqueous solution. By comparing the IR spectras of modified zeolite and unmodified zeolite, it is found that surfactant was successfully modified to the zeolite surface; and by comparing the adsorption capacities of modified zeolite and non-modified zeolite for Congo red, it is found the former is much larger than the latter. The effect of various adsorption parameters was investigated, etc. contact time, pH of solution, ions strength and the adsorbent amount. Results indicated that the adsorption equilibrium was reached in 70 min; adsorption capacity decreased with the increase of pH within 5-10; ions strength and the adsorbent amount also influenced adsorption. Finally, we applied Langmuir and Freundlich adsorption model to this adsorption and the experimental data perfectly obeyed Langmuir adsorption isotherm.
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