Al-MCM-41Synthesized By Kaolin And Study On Desorption Of Pollutants

Air and water are the natural resource for the survival of the people. With therapid development of industry, people’s living standard has been improved. At thesame time, environmental problems become increasingly serious, such as haze andeutrophication. So oil desulfurization and wastewater phosphorous removal becomeimperative.First, we get some acid soil with different Si/Al ratio after acid treatment andsynthesize mesoporous with different Si/Al ratio by hydrothermal method. It isdescribed that we synthesize the mesoporous with aluminum content of32.5%successfully characterized by XRD, BET and TEM. And we found that mesoporouscrystalinity and degree of order are increasing highly with the increasing Si/Al ratio,pore size distributes more and pore structure becomes more regular. Preparation ofAl-MCM-41using coal kaolin as silicon source is not only low cost but high aluminacontent can be synthesized. In addition, the pore of Al-MCM-41is regular andhydrothermal is stability. So it is feasible to prepare mesoporous molecular sieve bykaolin.Then, mesoporous molecular sieve prepared by coal measures kaolin is used forpollutant removal, including oil desulfurization and wastewater phosphorous.Molecular shows good performance on removal of thiophene. Al50-MCM-41showssignificant effect on removal of thiophene and sulfur capacity can reach7.2mg/g. Thedesulfurization performance of Al50-MCM-41is significantly increased after loadingthe metal component. It is a result of the σ-π bond synergy between metal andthiophene. Al50-MCM-41loading La2O3shows good performance in desulfurizationand it’s sulfurization capacity can reach17.86mg/g. Characterized byBET and TEM,the specific surface area and acid are major factors affecting the adsorption capacityof thiophene on zeolite. The more aluminum content, the better adsorption when as anadsorbent for removing phosphate. The adsorption performance of loading La2O3improved significantly. The larger the specific surface area of support, the better theadsorption. The adsorption capacity can reach52.8mg/g and phosphorus removal ratereaches83.2%when Al50-MCM-41loaded10%lanthanum. Finally, the sample adsorbed shows good regeneration performance byregeneration. The sulfur contents fell9.7%than freshly Al50-MCM-41, while theamount of phosphate recover over70%of the original.