关键词: 模板剂;疏水性;MCM-41-dry;U(VI);吸附

Abstract: Using hydrothermal synthesis prepared mesoporous silica material MCM-41 before and after calcination.The adsorption of MCM-41-dry and MCM-41-cal for uranium(VI) are studied with static experiment.The influence factors on the uranium(VI) removal rate such as pH, adsorption time, dosage and initial concentration were researched, at the same time the removal mechanism was analyzed with SEM, EDS, BET and FTIR.The results indicate that MCM-41-dry for uranium(VI) is better than MCM-41-cal because of having an organic templating agent.The optimum values of the parameters determined were 0.2 g/L for the dosage, 5 for the initial pH value, 180 min for the adsorption time, 30 ℃ for the temperature, 10 mg/L for the initial concentration of MCM-41-dry, the removal rate reaches 99.2%.It can be seen that the behavior of uranium(VI) adsorption onto MCM-41-dry is a Langmuir type isotherm and pseudo second-order kinetic model.When T=303 K, the theory adsorption capacity is 241.935 mg/g and adsorption is monolayer adsorption, basing on chemical adsorption.Through BET, FTIR characterization, the results indicate that MCM-41-dry can adsorb uranium(VI) with a hexagonal mesoporous structure, hydroxyl and amino functional groups play a significant role in adsorption.

Key words: templating agent;hydrophobic;MCM-41-dry;uranium(VI);adsorption