| 141 | 1 | 45 |
| 下载次数 | 被引频次 | 阅读次数 |
不添加有机模板剂,采用较廉价的硅酸钠和铝酸钠分别作为硅源和铝源,经由两步法合成粒度分布均匀且晶型较好的亚微米A型沸石。研究了经不同陈化时间后硅铝凝胶结构发生的变化及经过晶化后产物的粒径变化。结果表明:陈化时间为0~85h时,主要表现为诱导成核,在这段时期硅铝凝胶中对A型沸石成核过程有重要影响的四元环、双四元环数量显著增加,而陈化时间为85~139h主要表现为晶核的生长;随着陈化时间的延长硅铝凝胶中SiO2/Al2O3逐渐减小,且尺寸也逐渐变小;在0~85h区间,合成最终产物的平均粒径随着陈化时间延长而减小,在85h时最小,可达500nm左右;继续延长陈化时间至139h将导致小颗粒A型沸石发生团聚,且形貌也变的不规整。
Abstract：Submicron zeolite A was synthesized by a two-step method with organic template-free aluminosilicate gel system.The aluminosilicate gel was prepared with Na2SiO3·9H2O and NaAlO2 as silica and alumina source,respectively.The solid phase of aluminosilicate gel in the aging stage and the crystal size of the final products after crystallization at 100℃for 4h were investigated.The results indicate that in the nucleation period,the number of intermediate species of four-ring(4R)and double four-ring(D4R)increases when the aging time is 0--85 h.The nucleus grow when the aging time increases from85 hto 139h.The SiO2/Al2O3 ratio and the crystal size of the solid phase of aluminosilicate gel decrease with increasing the aging time.The crystal size of final products decreases with the increase of aging time,and it becomes the minimum size of ca.500 nm when the aging time is 85 h.The products become the aggregates of small particles with the irregular morphology when the aging time is 139 h.
[1]MERCEILLE A,WEINZAEPFEL E,BARRY,et al.The sorption behaviour of synthetic sodium nonatitanate and zeolite A for removing radioactive strontium from aqueous wastes[J].Sep Purif Technol,2012,96:81-88.
[2]张敏,肖质文,何红运.Cu-β沸石的合成、表征及催化性能[J].无机化学学报,2011,27(3):427-433.ZHANG Min,XIAO Zhiwen,HE Hongyun.Chin J Inorg Chem(in Chinese),2011,27(3):427-433.
[3]WHITE J C,DUTTA P K,SHQAU K,et al.Synthesis of ultrathin zeolite Y membranes and their application for separation of carbon dioxide and nitrogen gases[J].Langmuir,2010,26(12):10287-10293.
[4]TOSHEVA L,VALTCHEV V P.Nanozeolites:synthesis,crystallization mechanism,and applications[J].Chem Mater,2005,17(10):2494-2513.
[5]MINTOVA S,OLSON N H,VALTCHEV V P,et al.Mechanism of zeolite A nanocrystal growth from colloids at room tem-perature[J].Science,1999,283(5404):958-960.
[6]VALTCHEV V P,TOSHEVA L,BOZHILOV K N.Synthesis of zeolite nanocrystals at room temperature[J].Langmuir,2005,21(23):10724-10729.
[7]ALFARO S,RODRIGUEZ C,VALENZUELA M A,et al.Aging time effect on the synthesis of small crystal LTA zeolites in the absence of organic template[J].Mater Lett,2007,61(24):4655-4658.
[8]FAN W,OGURA M,SANKAR G,et al.In situ small-angle and wide-angle X-ray scattering investigation on nucleation and crystal growth of nanosized zeolite A[J].Chem Mater,2007,19(8):1906-1917.
[9]CUNDY C S,COX C A.The hydrothermal synthesis of zeolites:Precursors,intermediates and reaction mechanism[J].Microporous Mesoporous Mater,2005,82(1):1-78.
[10]熊晓云,范峰滔,马军,等.用高效NaY沸石导向剂快速合成A型沸石[J].高等学校化学学报,2007,28(1):21-25.XIONG Xiaoyun,FAN Fengtao,MA Jun,et al.Chem J Chin Univ(in Chinese),2007,28(1):21-25.
[11]李守贵,李锡凯,徐如人.L沸石导向剂陈化机制的研究[J].高等学校化学学报,1992,13(2):145-148.LI Shougui,LI Xikai,XU Ruren.Chem J Chin Univ(in Chinese),1992,13(2):145-148.
[12]YUSOF A M,NIZAM N A,RASHID N A A.Hydrothermal conversion of rice husk ash to faujasite-types and NaAtype of zeolites[J].J Porous Mater,2010,17(1):39-47.
[13]张敏,高丙莹,何红运.新型V-Ni-β沸石的合成、表征及催化性能[J].无机化学学报,2012,28(11):2355-2362.ZHANG Min,GAO Bingying,HE Hongyun.Chin J Inorg Chem(in Chinese),2012,28(11):2355-2362.
[14]YAO J F,YU L,ZHANG L X,et al.Influence of glycerol cosolvent on the synthesis of size controllable zeolite A[J].Mater Lett,2011,65(14):2304-2306.
[15]REN L M,LI C J,FAN F T,et al.UV-raman and NMR spectroscopic studies on the crystallization of zeolite Aand a new synthetic route[J].Chem Eur J,2011,17(22):6162-6169.
[16]DUTTA P K,SHIEH D C.Crystallization of Zeolite A:A spectroscopic study[J].J Phys Chem,1986,90(11):2331-2334.
[17]FAN F T,FENG Z C,LI G N,et al.In situ UV raman spectroscopic studies on the synthesis mechanism of zeolite X[J].Chem Eur J,2008,14(17):5125-5129.
[18]马淑杰,刘孔凡,崔美珍,等.A型沸石的生成机理[J].高等学校化学学报,1984,5(2):158-162.MA Shujie,LIU Kongfan,CUI Meizhen,et al.Chem J Chin Univ(in Chinese),1984,5(2):158-162.
[19]王仰东,刘杨,董家禄,等.小晶粒A型分子筛的合成及其晶貌[J].催化学报,1998,19(6):610-612.WANG Yangdong,LIU Yang,Dong Jialu,et al.Chin J Catal(in Chinese),1998,19(6):610-612.
[20]王建,董家禄,刘杨,等.偏高岭土合成4A沸石机理的研究[J].无机化学学报,2000,16(1):31-36.WANG Jian,DONG Jialu,LIU Yang,et al.Chin J Inorg Chem(in Chinese),2000,16(1):31-36).
[21]黄先亮,王正宝,无模板剂两步法合成小颗粒ZSM-5沸石团聚体[J].催化学报,2011,32(11):1702-1711.HUANG Xianliang,WANG Zhengbao.Chin J Catal(in Chinese),2011,32(11):1702-1711.
[22]张铨昌.沸石分子筛的合成与应用[J].硅酸盐学报,1992,20(6):544-550.ZHANG Quanchang.J Chin Ceram Soc,1992,20(6):544-550.
[23]ADNADJEVIC B,VUKICEVIC J,FILIPOVIC-ROJKA Z,et al.The influence of NaX zeolite particle size on crystallinity measured by the XRD method[J].Zeolites,1990,10(7):699-702.
基本信息:
中图分类号:TB383.4
引用信息:
[1]刘艳娜,白璞,龙丽,等.无模板两步法合成亚微米A型沸石[J].硅酸盐学报,2014,42(10):1325-1331.
基金信息:
国家自然科学基金项目(21301079);; 昆明理工大学科学研究基金项目(kkz3201205022);; 昆明理工大学大学生创新创业训练计划(201310674222);; 昆明理工大学分析测试基金项目(20140438)
2014-03-19
2014
2014-08-12
2014-08-11
2014
1
2014-09-22
2014-09-22
2014-09-22