The Preparation Of Functionalized Mesoporous/microporous Materials And The Application On The Adsorption Performance Of The Heavy Metal Ions

Due to the rapid development of the modern industry, the pollution of the heavy metal ions is getting worse in the soil and water. The emission of the heavy metal ions into the environment what was difficult to be degraded,easy to be enriched and high toxicity.So it is a great threat to the people’s health and the environment.Now,there are various ways to deal with the heavy metal ions:chemical precipitation.electrochemical method,ion exchange and adsorption.Among those methods,adsorption is widely used to handle with the polluted water, due to it is easier to operation,low cost and high efficiency.In recent year,researchers continue to explore novel and efficient adsorbent to replace traditional adsorbent.Mesoporous materials are attracting people’s attention especially SBA-15, due to the large specific surface area, uniform pore size and stable structure.When the SBA-15is modified by chemical method,its hydrothermal stability and chemical activity have been greatly improved.Organic microporous materials own a bigger BET surface area than mesoporous materials and easy to introduce various functional groups to the carbon chain.The final functional organic materials have a better physical/chemical stability and thermal stability. This thesis involves four aspects of studies:1.The bifunctional SBA-15with different contents of amino and thiol groups is synthesized through condensation method,and the obtained materials are characterized by the FT-IR,SAXRD,BET and EA(elemental analysis).Then the materials are used to adsorb the Cr(VI) in the water and explore the optimal conditions among the adsorption process.In order to further study the adsorption mechanism,the adsorption kinetics.adsorption isothermal and thermodynamic parameters were used to analyze the experimental datas.2.For investigating the influence of the proportion of NH2and SH during the the synthesis process and the influence of the functional groups on the adsorption properties.So through change the ratios of NH2/SH,prepares the SBA-NH2-SH which contains different ratios of NH2/SH.The obtained materials also measured by amount ways.Based on the EA datas,there is a competitive relationship between amino and thiol groups and the thiol group is more easy to graft onto the surface of the SBA-15.Using the samples to adsorb Cr(VI),the result show that the thiol group plays a leading role in the process of the bifunctional SBA-15adsorbs Cr(VI). While adding the amino group not only increase the number of the thiol group that is grafted onto the surface of SBA-15,but also can help increase the adsorption capacity of Cr(VI).3. The functional organic polymers with different contents of amino group is made using the simple Friedel-Crafts alkylation reaction,the samples is tested by FT-IR,BET and EA.Using simple dynamic adsorption unit to study the adsorbent dynamic adsorption to the Cr(Ⅵ) and discussing the optimum dynamic adsorption conditions,next use the Thomas model to investigate the experimental datas.The results demonstrate30%MOPs-NH2(30%represent the molar percent of p-Toluidine/30mmol)has a large adsorption capacity and Thomas model could better describ the process of the dynamic adsorption.At last the reusability of the sample was studied,finding after three desorption,the30%MOPS-NH2also remove above50%Cr(VI) in the solution.4.The NH2/SH bifunctional organic polymer(MOPs-NH2-SH) is synthesized by Friedel-Crafts alkylation reaction,the FT-IR、BET and other testing methods are used to examine the adsorbent,then they are used to deal with the Cr(VI) in the solution.The results indicate:when the contents of the groups are between10%and40%,the MOPS-NH2-SH exhibits an excellent adsorption properties,while once the contents over40%,the adsorption properties is getting worse.Among the experiment process,we found the hydrophobicity of the material is more high duo to the material floats on the solution surface after6h stirring.So the60%MOPs-NH2-SH is picked up to oxidized to60%MOPs-NH2-SO3H,then make a comparison of the adsorption capacity between the two materials,finding the MOPS-NH2-SO3H have a high adsorption capacity than MOPs-NH2-SH,so the hydrophobicity indeed affect the MOPs-NH2-SH adsorption properties.And the adsorption kinetics,adsorption thermodynamics and reusability also are systematic studied.