The Preparation Of Mesoporous Alumina By Lyotropic Liquid Crystal

Mesoporous alumina is a kind of emerging material that better than the traditional alumina. Because of its large specific surface area, pore size distribution, high thermal stability, easy to get many metals and other characteristics,it has been more and more used in catalysis, adsorption and separation, bio medicine and so on.Lyotropic liquid crystal is easy to control the structure and has the characteristics of anisotropy. Lyotropic liquid crystal template method was introduced into the synthesis of nanomaterials, which exhibits the unique ability to control particles size, morphology and surface area.In this study, the mesoporous alumina were synthesized by using lyotropic liquid crystal template. Built ternary system of SDS/C5H11OH/H2 O and CTAB/C10H21OH/H2 O,Inspect the effects of surfactant concentration, solvent concentration and water content on lyotropic liquid crystal. When SDS:C5H11OH=8:2, water content is 50%,SDS/C5H11OH/H2 O is the most ideal lyotropic liquid crystalline;When CTAB:C10H21OH=5:5, water content is 60%, CTAB/C10H21OH/H2 O is the most ideal lyotropic liquid crystalline, Because of the lyotropic liquid crystalline is uniform distribution in the SDS/C5H11OH/H2 O,so we chose SDS/C5H11OH/H2 O system.Using aluminum chloride as aluminum source, ammonia as precipitant, instead of water.Inspect the effects of concentration of precipitation agent, the aluminum source for mesoporous alumina particle size distribution as well as the calcination temperature on the crystalline.Using TG, XRD and FTIR techniques,etc.Results show that sample was obtained from the concentration of 0.5mol/L aluminum chloride solution as the source of aluminum, with the mass fraction of 25%ammonia as precipitator, and the temperature was 700.The sample is alumina, the average pore diameter of the sample was about 6.5 nm, the specific surface area is about400 m2/g, the alumina is mesoporous,reach the goal.