三氟三氯乙烷加氢脱氯Pd-Cu催化剂失活分析

doi:10.16085/j.issn.1000-6613.2022-0526

摘要/Abstract

摘要：

以活性炭为催化剂载体，采用浸渍法制备Pd、Cu、Pd-Cu三种催化剂，将催化剂应用于三氟三氯乙烷（CFC-113）加氢脱氯制三氟氯乙烯（CTFE）的反应，考察Cu的引入对Pd催化剂性能的影响。对反应前后及再生的Pd-Cu催化剂进行X射线衍射（XRD）、X射线光电子能谱（XPS）、氮气吸附-脱附（BET）、氢气程序升温还原（H₂-TPR）、热重（TG）、氨气程序升温脱附（NH₃-TPD）等表征分析。研究表明，Pd催化剂具有较高的加氢脱氯性能，其主要产物为三氟乙烷，Cu的加入有利于提高CTFE的选择性。这应与Cu、Pd之间存在相互作用并形成合金，抑制了Pd的脱氯性能有关。反应后的催化剂存在表面结焦、反应过程中吸附Cl以及金属Cu价态变化和迁移等现象，其中表面高沸物的形成、卤元素吸附导致的金属迁移和Cu-Pd相互作用的改变是Pd-Cu催化剂失活的主要原因。

关键词: 加氢, 脱氯, 三氟氯乙烯, 催化剂, 失活

Abstract:

Using activated carbon as the catalyst carrier, we prepared three catalysts of Pd/AC, Cu/AC and Cu-Pd/AC by impregnation method. The catalysts were applied to trifluorochloroethane hydrodechlorination to prepare trifluorochloroethylene. The effect of Cu introduction on the performance of the catalysts was studied. The properties of fresh, spent, and regenerated Pd-Cu catalysts were measured using XRD, XPS, BET, H₂-TPR, TG and NH₃-TPD. The results showed that the Pd catalyst had good hydrodechlorination performance, and the main product was trifluoroethane. The addition of Cu was beneficial to improve the selectivity of chlorotrifluoroethylene. This should be related to the interaction between Cu and Pd and the formation of alloys, which inhibited the dechlorination. Surface coking, adsorption of Cl, and the change and migration of the valence state of the metal Cu were observed on the catalyst. The formation of high boiling species on surface, metal migration due to halogen adsorption, and changes in Cu-Pd interaction were the main reasons for the deactivation of Pd-Cu catalysts.

Key words: hydrogenation, dechlorination, chlorotrifluoroethylene, catalyst, deactivation

中图分类号:

O643.36

陆子薇, 廖湘洲, 粟小理, 隋志军. 三氟三氯乙烷加氢脱氯Pd-Cu催化剂失活分析[J]. 化工进展, 2023, 42(1): 282-288.

LU Ziwei, LIAO Xiangzhou, SU Xiaoli, SUI Zhijun. Deactivation of Pd-Cu catalyst for hydrodechlorination of trifluorotrichloroethane[J]. Chemical Industry and Engineering Progress, 2023, 42(1): 282-288.

图/表 11

图1 加氢脱氯活性评价装置1—原料罐；2—原料泵；3—N2质量流量计；4—H2质量流量计；5—预热器；6—固定床反应器；7—碱洗瓶；8—干燥器

图2 三种催化剂催化CFC-113的反应性能影响

图3 反应温度对Pd-Cu催化剂反应性能的影响

图4 Pd-Cu催化剂的稳定性

图5 Pd-Cu催化剂的失活再生性能

表1 载体及Pd-Cu催化剂反应前后的物理性质

样品	S_BET /m²·g^-1	V_P /cm³·g^-1	D_P /nm	Cu晶粒^① /nm	Pd分散度^② /%	Pd粒径^② /nm
载体	908	0.695	3.06	—	—	—
Pd-Cu(F)	798	0.568	2.85	9.1	77.84	1.20
Pd-Cu(U)	637	0.481	3.02	—	61.82	1.51
Pd-Cu(R)	720	0.503	2.79	10.6	72.93	1.28

图6 Cu催化剂和Pd-Cu催化剂反应前后XRD图

图7 三种催化剂焙烧后的H2-TPR图

图8 Pd-Cu催化剂反应前后及再生后的TG图

图9 Pd-Cu催化剂反应前后的XPS谱图

图10 Pd-Cu催化剂反应前后及再生的NH3-TPD谱图

参考文献 22

1	陈淼, 李玲, 刘武灿. CFC-113气固相加氢脱氯制备三氟氯乙烯的研究进展[J]. 有机氟工业, 2013(1): 26-29.
	CHEN Miao, LI Ling, LIU Wucan. Research progress on the preparation of trifluorochloroethylene by gas-solid phase hydrodechlorination of CFC-113[J]. Organo-Fluorine Industry, 2013(1): 26-29.
2	赵洋, 蔚辰刚, 周强, 等. Y-Mg-Al-F催化剂用于1, 1, 1, 2-四氟乙烷裂解制备三氟乙烯[J]. 应用化学, 2014, 31(4): 400-405.
	ZHAO Yang, YU Chengang, ZHOU Qiang, et al. Performance of Y-Mg-Al-F catalysts for catalytic pyrolysis of 1, 1, 1, 2-tetrafluoroethane to trifluoroethylene[J]. Chinese Journal of Applied Chemistry, 2014, 31(4): 400-405.
3	李玲, 刘武灿, 石能富, 等. 三氟氯乙烯的合成及性质[J]. 浙江化工, 2015, 46(3): 7-11.
	LI Ling, LIU Wucan, SHI Nengfu, et al. Preparation and properties of trifluorochloroethylene[J]. Zhejiang Chemical Industry, 2015, 46(3): 7-11.
4	BELMORE E, EWALT W, WOJCIK B. Production of polyperfluorovinyl chloride [J]. Industrial & Engineering Chemistry, 1947, 39(3): 338-342.
5	MORI Tohru, YASUOKA Tae, MORIKAWA Yutaka. Hydrodechlorination of 1, 1, 2-trichloro-1, 2, 2-trifluoroethane (CFC-113) over supported ruthenium and other noble metal catalysts[J]. Catalysis Today, 2004, 88(3/4): 111-120.
6	OHNISHI Ryuichiro, WANG Wenliang, ICHIKAWA Masaru. Selective hydrodechlorination of CFC-113 on Bi- and Tl-modified palladium catalysts[J]. Applied Catalysis A: General, 1994, 113(1): 29-41.
7	LEROT L, WILMET V, PIROTTON J. Process for preparation of chlorotrifluoroethylene and of trifluoroethylene from 1,1,2-trichloro-trifluoroethane and catalytic composition used in this process: EP 0747337B[P]. 2000-12-27.
8	蔡光宇, 李文双. 催化加氢脱氯制取三氟氯乙烯和三氟乙烯所用催化剂: CN1351903A[P]. 2002-06-05.
	CAI Guangyu, LI Wenshuang. Catalystic hydrogenation and dechlorination catalyst for preparing trifluorochloroethylene and trichloroethylene: CN1351903A[P]. 2002-06-05.
9	蔡光宇, 李文双, 马振彦. CFC-113催化剂加氢脱氯制取三氟氯乙烯的催化剂及其制备方法: CN1460549A [P]. 2003-12-10.
	CAI Guangyu, LI Wenshuang, MA Zhenyan. Catalyst for preparing trifluorochloroethylene by using CFC-113 catalytic hydro-dechlorination and its preparation method: CN1460549A [P]. 2003-12-10.
10	李猷, 曹育才. 氯氟烃加氢脱氯催化剂的研究进展[J]. 化工进展, 2004, 23(1): 47-50.
	LI You, CAO Yucai. Advance in catalytic hydrodechlorination of chlorofluorocarbons[J]. Chemical Industry and Engineering Progress, 2004, 23(1): 47-50.
11	THOMPSON C D, RIOUX R M, CHEN N, et al. Turnover rate, reaction order, and elementary steps for the hydrodechlorination of chlorofluorocarbon compounds on palladium catalysts[J]. The Journal of Physical Chemistry B, 2000, 104(14): 3067-3077.
12	AGARWAL Shirish, AL-ABED Souhail R, DIONYSIOU Dionysios D. Enhanced corrosion-based Pd/Mg bimetallic systems for dechlorination of PCBs[J]. Environmental Science & Technology, 2007, 41(10): 3722-3727.
13	WANG Zhiqin. Catalytic hydrodecorination of 1,2-dicoroehtane over Pd-Cu/γ-Al₂O₃ catalysts[J]. Environmental Chemistry, 2012, (2): 144-149.
14	FANG Deren, LI Wanjun, ZHAO Jinbo, et al. Catalytic hydrodechlorination of 4-chlorophenol over a series of Pd-Cu/γ-Al₂O₃ bimetallic catalysts[J]. RSC Advances, 2014, 4(103): 59204-59210.
15	MUKHERJEE Parthasarathi, ROY Partha Sarathi, MANDAL Kaustab, et al. Improved catalysis of room temperature synthesized Pd-Cu alloy nanoparticles for anodic oxidation of ethanol in alkaline media[J]. Electrochimica Acta, 2015, 154: 447-455.
16	SOARES O S G P, ÓRFÃO J J M, RUIZ-MARTÍNEZ J, et al. Pd-Cu/AC and Pt-Cu/AC catalysts for nitrate reduction with hydrogen: influence of calcination and reduction temperatures[J]. Chemical Engineering Journal, 2010, 165(1): 78-88.
17	刘文栋, 张成会, 陈传霞, 等. 超薄钯铜纳米片组装纳米花的构建及其氧还原性能[J]. 化工进展, 2021, 40(11): 6246-6253.
	LIU Wendong, ZHANG Chenghui, CHEN Chuanxia, et al. Engineering ultrathin PdCu nanosheets-composed nanoflowers with high catalytic activity for oxygen reduction reaction[J]. Chemical Industry and Engineering Progress, 2021, 40(11): 6246-6253.
18	WIERSMA Andre, VAN DE SANDT Emile J A X, DEN HOLLANDER Marion A, et al. Comparison of the performance of activated carbon-supported noble metal catalysts in the hydrogenolysis of CCl₂F₂ [J]. Journal of Catalysis, 1998, 177(1): 29-39.
19	FENG Yafen, WANG Li, ZHANG Yanhui, et al. Deactivation mechanism of PdCl₂-CuCl₂/Al₂O₃ catalysts for CO oxidation at low temperatures[J]. Chinese Journal of Catalysis, 2013, 34(5): 923-931.
20	JIANG Zhao, GONG Xiang, GUO Shuyi, et al. Engineering PdCu and PdNi bimetallic catalysts with adjustable alloying degree for the dehydrogenation reaction of dodecahydro-N-ethylcarbazole[J]. International Journal of Hydrogen Energy, 2021, 46(2): 2376-2389.
21	WEN Chao, YIN Anyuan, CUI Yuanyuan, et al. Enhanced catalytic performance for SiO₂-TiO₂ binary oxide supported Cu-based catalyst in the hydrogenation of dimethyloxalate[J]. Applied Catalysis A: General, 2013, 458: 82-89.
22	PLATZMAN Ilia, BRENER Reuven, HAICK Hossam, et al. Oxidation of polycrystalline copper thin films at ambient conditions[J]. The Journal of Physical Chemistry C, 2008, 112(4): 1101-1108.

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