体系pH值对微波辅助水热合成ZSM-5分子筛结构性质的影响
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摘要
采用微波辅助水热合成法制备了ZSM-5分子筛,借助XRD、SEM、BET、NH3-TPD等表征手段,考察了体系pH值对ZSM-5分子筛结构性质的影响。结果表明,体系pH值对ZSM-5分子筛的微观形貌、比表面积、孔径分布和表面酸强度有较大影响。pH值为11时,制得的ZSM-5分子筛样品的纯度较高,微观形貌为六棱柱状,晶粒分散较好,晶粒尺寸较小且均匀(200nm左右),具有较大的比表面积(313 m~2·g~(-1))和较小的平均孔径(2.39 nm),表面化学性质以弱酸为主。
ZSM-5 molecular sieves were prepared by microwave-assisted hydrothermal synthesis method. The effects of system pH on the structural properties of ZSM-5 zeolite were investigated by characterization means such as XRD, SEM, BET and NH3-TPD.The results showed: the pH had a great influence on the morphology, specific surface area, pore size distribution and the surface acid strength of the synthesized ZSM-5 zeolite. When the pH value was 11, the prepared ZSM-5 zeolite had higher purity, the microscopic shape was a hexagonal prism and performed better dispersibility, it had more smaller and uniform grain size(about 200 nm), larger specific surface(313 m~2/g)and minimum average pore size(2.39 nm), and the surface chemistry was dominated by weak acids.
ZSM-5 molecular sieves were prepared by microwave-assisted hydrothermal synthesis method. The effects of system pH on the structural properties of ZSM-5 zeolite were investigated by characterization means such as XRD, SEM, BET and NH3-TPD.The results showed: the pH had a great influence on the morphology, specific surface area, pore size distribution and the surface acid strength of the synthesized ZSM-5 zeolite. When the pH value was 11, the prepared ZSM-5 zeolite had higher purity, the microscopic shape was a hexagonal prism and performed better dispersibility, it had more smaller and uniform grain size(about 200 nm), larger specific surface(313 m~2/g)and minimum average pore size(2.39 nm), and the surface chemistry was dominated by weak acids.
引文
[1]张宝忠. ZSM-5分子筛的纳米化、核壳化及其催化性能研究[D].北京:北京有色金属研究总院,2015.
[2]徐如人,庞文琴,霍启升.分子筛与多孔材料化学(第2版)[M].北京:科学出版社,2015.
[3]Gao X F, Ding C M, Liu W L, et al. Effect of Shape andModificationoverZSM-5CatalystonMethanol to Gasoline[J]. Advanced Materials Research, 2014,1008/1009:295-299.
[4]谭可心,栾国颜,裴东寒.预晶化液法合成纳米级ZSM-5分子筛[J].化工技术与开发,2016(12):13-15.
[5]潘红艳,田敏,赵敏,等.硅铝比对ZSM-5分子筛催化甲醇制烯烃性能的影响[J].天然气化工(C1化学与化工),2015(1):9-12.
[6]孙书红,王宁生,闫伟建. ZSM-5沸石合成与改性技术进展[J].工业催化,2007,15(6):6-10.
[7]吴伟,苏晓芳,白雪峰.一种两步微波辐射加热的晶种引导法快速合成纳米ZSM-5分子筛的方法:CN,104876240A[P]. 2015.
[8]Thubsuang U, Ishida H, Wongkasemjit S, et al. Novel template confinement derived from polybenzoxazinebased carbon xerogels for synthesis of ZSM-5 nanoparticles via microwave irradiation[J]. Microporous&Mesoporous Materials, 2012, 156(3):7-15.
[9]Mahabole M, Lakhane M, Choudhari A, et al. Dielectric and ethanol sensing studies on synthesized nano-ZSM-5zeolite[J]. Indian Journal of Physics, 2015, 89(2):167-174.
[10]Motuzas J, Julbe A, Noble R D, et al. Rapid synthesis of silicalite-1 seeds by microwave assisted hydrothermal treatment[J]. Microporous&Mesoporous Materials, 2005,80(1/3):73-83.
[11]Brar T, France P, Smirniotis P G. Control of Crystal Size and Distribution of Zeolite A[J]. Industrial&Engineering Chemistry Research, 2001, 40(4):1133-1139.
[2]徐如人,庞文琴,霍启升.分子筛与多孔材料化学(第2版)[M].北京:科学出版社,2015.
[3]Gao X F, Ding C M, Liu W L, et al. Effect of Shape andModificationoverZSM-5CatalystonMethanol to Gasoline[J]. Advanced Materials Research, 2014,1008/1009:295-299.
[4]谭可心,栾国颜,裴东寒.预晶化液法合成纳米级ZSM-5分子筛[J].化工技术与开发,2016(12):13-15.
[5]潘红艳,田敏,赵敏,等.硅铝比对ZSM-5分子筛催化甲醇制烯烃性能的影响[J].天然气化工(C1化学与化工),2015(1):9-12.
[6]孙书红,王宁生,闫伟建. ZSM-5沸石合成与改性技术进展[J].工业催化,2007,15(6):6-10.
[7]吴伟,苏晓芳,白雪峰.一种两步微波辐射加热的晶种引导法快速合成纳米ZSM-5分子筛的方法:CN,104876240A[P]. 2015.
[8]Thubsuang U, Ishida H, Wongkasemjit S, et al. Novel template confinement derived from polybenzoxazinebased carbon xerogels for synthesis of ZSM-5 nanoparticles via microwave irradiation[J]. Microporous&Mesoporous Materials, 2012, 156(3):7-15.
[9]Mahabole M, Lakhane M, Choudhari A, et al. Dielectric and ethanol sensing studies on synthesized nano-ZSM-5zeolite[J]. Indian Journal of Physics, 2015, 89(2):167-174.
[10]Motuzas J, Julbe A, Noble R D, et al. Rapid synthesis of silicalite-1 seeds by microwave assisted hydrothermal treatment[J]. Microporous&Mesoporous Materials, 2005,80(1/3):73-83.
[11]Brar T, France P, Smirniotis P G. Control of Crystal Size and Distribution of Zeolite A[J]. Industrial&Engineering Chemistry Research, 2001, 40(4):1133-1139.