Studies on the Synthesis, Properties and Preparation Methods of Zeolite ZK-4
Studies on the Synthesis, Properties and Preparation Methods of Zeolite ZK-4作者机构:Hunan Normal Univ Dept Chem Changsha 410081 Peoples R China
出 版 物:《Chemical Research in Chinese Universities》 (高等学校化学研究(英文版))
年 卷 期:2000年第16卷第4期
页 面:306-312页
核心收录:
学科分类:081705[工学-工业催化] 08[工学] 0817[工学-化学工程与技术]
主 题:Zeolite ZK-4 Molecular sieve Zeolite synthesis Property,Tetramethylammonium hydroxide template
摘 要:A zeolite designated as ZK-4 was synthesized hydrothermally in the system (TMA)2ONa2O-Al2O3- SiO2- H2O at 80 - 100℃ with tetramethylammonium hydroxide as an organic templating agent. The pure zeolite ZK-4 could be prepared by using the mother liquor obtained after filtration as the source of templating agent. The effect of some synthetic conditions such as the amount of tetramethylammonium hydroxide used, n [ (TMA)2O + Na2O] /n (Al2O3) ratio, n (SiO2)/n(Al2O3) ratio and crystallization time, etc. on the crystalline phase of the product was investigated. When the following molar ratios of the reaction mixture, n (SiO2)/n (Al2O3) 4-10, n[(TMA)2O+Na2O]/ n (Al2O3 ) 7, n (Na2O)/n (Al2O3)=0. 5-2. 0, n (H2O)/ n(A12O3)=80-450, were used, pure zeolite ZK-4 could be obtained. The synthetic products were characterized by X-ray powder diffraction, atomic absorption spectrophotometry (AAS), adsorption measurement, thermogravimetric analysis(TGA), and 29Si magic angle spinning nuclear magnetic resonance technique. Zeolite ZK-4 has a higher thermal stability than sodium zeolite A due to higher n(Si)/n(Al) ratio of zeolite ZK-4.