Page 154 - 《精细化工》2022年第9期
P. 154
第 39 卷第 9 期 精 细 化 工 Vol.39, No.9
2022 年 9 月 FINE CHEMICALS Sept. 2022
催化与分离提纯技术
SAPO-34 的改性及其在合成气制
低碳烯烃中的应用
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梁晓彤,王丽娜,李 忠 ,孟凡会
(太原理工大学,省部共建煤基能源清洁高效利用国家重点实验室,山西 太原 030024)
摘要:采用水热法合成不同金属(Ce、Zn、Zr)及不同 Zr 掺杂量改性的 SAPO-34 分子筛,并与 GaZrO x 金属氧
化物物理混合制备 GaZrO x /SAPO-34 双功能催化剂,考察其催化合成气制低碳烯烃(STO)的反应性能。采用
XRD、TEM、SEM-EDS、BET、FTIR、NH 3 -TPD、XPS 对分子筛进行了表征。结果表明,不同金属改性的分子
筛均合成了具有 CHA 结构的 SAPO-34,掺杂 Zr 提高了分子筛的相对结晶度,减小了颗粒尺寸。Zr 掺杂量为 1.0%
〔n(ZrO 2 )∶n(Al 2 O 3 ) = 1∶100〕时合成的 1.0% ZrSP-34 分子筛颗粒尺寸最小,平均粒径为 0.53 μm,且强酸量适
中(1.34 mmol/g);Zr 掺杂量为 2.0%时导致多余的 Zr 以 ZrO 2 形式存在于分子筛表面,覆盖了强酸中心。与未
改性的 SAPO-34 相比,采用 1.0% ZrSP-34 制备的 GaZrO x /1.0% ZrSP-34 双功能催化剂可使 CO 转化率从 14.2%
增加到 21.2%,低碳烯烃选择性从 71.0%提高至 82.4%,且该催化剂反应 60 h 后未出现明显失活。
关键词:合成气;低碳烯烃;分子筛改性;颗粒尺寸;酸性质;催化技术
中图分类号:TQ630 文献标识码:A 文章编号:1003-5214 (2022)09-1872-10
Modification of SAPO-34 and its application in syngas
conversion to light olefins
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LIANG Xiaotong, WANG Lina, LI Zhong , MENG Fanhui
(State Key Laboratory of Clean and Efficient Coal Utilization, Taiyuan University of Technology, Taiyuan 030024,
Shanxi, China)
Abstract: A series of modified SAPO-34 zeolites with different metal (Ce, Zn, Zr) doping and Zr contents
were synthesized via hydrothermal method, and physically mixed with GaZrO x to obtain GaZrO x/SAPO-34
bifunctional catalyst, whose catalytic performance for syngas to light olefins (STO) was further investigated.
Structural characterization by XRD, TEM, SEM-EDS, BET, FTIR, NH 3-TPD and XPS indicated that all the
synthesized SAPO-34 samples displayed CHA structure with metal Zr doping leading to the relative
crystallinity improvement and particle size reduction. The synthesized sample with Zr doping content of
1.0% [n(ZrO 2)∶n(Al 2O 3) = 1∶100] exhibited the smallest particle size with an average particle size of
0.53 μm as well as a moderate amount of strong acid (1.34 mmol/g), while 2.0% ZrSP-34 zeolite led to
particle surface, especially the strong acid center, covered by ZrO 2 formed by excess of Zr. Compared with
the ones prepared from unmodified SAPO-34, GaZrO x/1.0% ZrSP-34 bifunctional catalyst could increase
CO conversion from 14.2% to 21.2% and light olefins selectivity from 71.0% to 82.4% with no significant
deactivation after 60 h of reaction.
Key words: syngas; light olefins; zeolite modification; particle size; acidity; catalysis technology
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低碳烯烃(C 2~4 )是石油化工行业的基本原料, 源不足,且对低碳烯烃的需求不断增长,迫切需要
其传统生产技术强烈依赖于石油资源。中国石油资 开发一种非石油资源生产烯烃的路线。近年来,甲
收稿日期:2022-03-09; 定用日期:2022-05-17; DOI: 10.13550/j.jxhg.20220207
基金项目:国家自然科学基金重点项目(U1510203);山西省自然科学基金(202103021224073);山西省重点研发计划(201803D421011)
作者简介:梁晓彤(1997—),女,硕士生,E-mail:liangxiaotong0507@link.tyut.edu.cn。联系人:李忠(1964—),男,教授,E-mail:
lizhong@tyut.edu.cn;孟凡会(1981—),男,副教授,mengfanhui@tyut.edu.cn。