Mg改性L分子筛负载Pt重整催化剂的制备及其石脑油芳构化性能

doi:10.16085/j.issn.1000-6613.2018-1258

摘要/Abstract

摘要：

为克服常规氧化铝型重整催化剂氯离子流失及对设备产生腐蚀等问题，通过离子交换法制备了Mg²⁺改性的L分子筛，采用浸渍法制备了不含氯离子的Pt/MgL重整催化剂，对分子筛载体进行了XRD、N₂吸附-脱附、NH₃-TPD和Py-IR等表征，并以硫含量0.50μg/mL工业精制石脑油为原料在固定床微反装置上评价了催化剂重整芳构化性能。结果表明，Mg²⁺离子交换对L分子筛的骨架结构没有破坏，Mg²⁺的存在提高了载体的酸量和酸强度，Mg²⁺改性的Pt/MgL催化剂重整芳构化性能明显提高，适当强酸性对L分子筛重整催化剂芳构化反应起到显著的促进作用。

关键词: 催化重整, L分子筛, 离子交换, 芳构化, 镁

Abstract:

In order to overcome the problems of chlorine loss and equipment corrosion caused by conventional alumina-type catalytic reforming catalyst, the Mg²⁺ modified zeolite L carrier (MgL) was obtained by ion exchange method and then the platinum supported reforming catalyst (Pt/MgL) without any chlorine was prepared by impregnation method. Characterizations by the use of XRD, N₂ adsorption-desorption, NH₃-TPD and Py-IR were carried out to analyze the physical properties of KL and MgL. Catalytic aromatization performance of the prepared reforming catalyst was investigated in a continuous-flow fixed-bed micro-reaction evaluation unit in which the industrial hydrofining naphtha with sulfur content of 0.50μg/mL was used as the feedstock. The results showed that the framework structure of zeolite L was not destroyed by the Mg²⁺ ion exchange. The presence of Mg²⁺ increased obviously the acid content and acid strength of the carrier, and thus the Mg²⁺ modified catalyst Pt/MgL promoted remarkably the aromatization performance. Proper high acidity played a significant role in the aromatization reaction over zeolite L reforming catalyst.

Key words: catalytic reforming, zeolite L, ion exchange, aromatization, magnesium

中图分类号:

O643.3
TE624

张鹏, 刘坚, 喻昊, 王更更, 胡长禄, 杨英, 刘百军. Mg改性L分子筛负载Pt重整催化剂的制备及其石脑油芳构化性能[J]. 化工进展, 2019, 38(04): 1753-1757.

Peng ZHANG, Jian LIU, Hao YU, Genggeng WANG, Changlu HU, Ying YANG, Baijun LIU. Preparation of Mg²⁺ modified zeolite L catalyst supported with Pt and its aromatization performance for naphtha catalytic reforming[J]. Chemical Industry and Engineering Progress, 2019, 38(04): 1753-1757.

图/表 7

参考文献 21

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分子筛	比表面积/m²·g^-1			孔体积/mL·g^-1
分子筛	S _T ^①	S _mic ^②	S _mes ^③	V _T ^④	V _mic ^⑤	V _mes ^⑥
KL	266	220	46	0.26	0.12	0.14
MgL	270	224	46	0.26	0.12	0.14

分子筛	比表面积/m²·g^-1			孔体积/mL·g^-1
分子筛	S _T ^①	S _mic ^②	S _mes ^③	V _T ^④	V _mic ^⑤	V _mes ^⑥
KL	266	220	46	0.26	0.12	0.14
MgL	270	224	46	0.26	0.12	0.14

分子筛	弱酸量^①	中等酸量^②	强酸量^③	总酸量
KL	199.5	130.5	9.6	339.6
MgL	441.6	965.6	269.6	1676.8
Al₂O₃-Cl	333.3	1150.8	203.9	1688.0

分子筛	弱酸量^①	中等酸量^②	强酸量^③	总酸量
KL	199.5	130.5	9.6	339.6
MgL	441.6	965.6	269.6	1676.8
Al₂O₃-Cl	333.3	1150.8	203.9	1688.0

分子筛	总酸量^①/μmol·g^-1				强酸量^②/μmol·g^-1
分子筛	L酸	B酸	B+L	B/L	L酸	B酸	B+L	B/L
KL	93.2	0	93.2	0	8.9	0	8.9	0
MgL	338.1	148.4	486.5	0.08	219.9	38.7	258.6	0.18
Al₂O₃-Cl	340.3	0	340.3	0	196.5	0	196.5	0