CIESC Journal ›› 2021, Vol. 72 ›› Issue (9): 4685-4697.DOI: 10.11949/0438-1157.20201937
• Catalysis, kinetics and reactors • Previous Articles Next Articles
Jiahao LIANG1(),Guoqiang ZHANG1,Yuan GAO2,Jiao YIN1,Huayan ZHENG1,Zhong LI1()
Received:
2020-12-29
Revised:
2021-03-19
Online:
2021-09-05
Published:
2021-09-05
Contact:
Zhong LI
梁家豪1(),张国强1,高源2,尹娇1,郑华艳1,李忠1()
通讯作者:
李忠
作者简介:
梁家豪(1995—),男,硕士,基金资助:
CLC Number:
Jiahao LIANG, Guoqiang ZHANG, Yuan GAO, Jiao YIN, Huayan ZHENG, Zhong LI. Effect of mesoporous construction on catalytic performance of CuY methanol oxidative carbonylation[J]. CIESC Journal, 2021, 72(9): 4685-4697.
梁家豪, 张国强, 高源, 尹娇, 郑华艳, 李忠. 介孔构建对CuY甲醇氧化羰基化反应活性的影响[J]. 化工学报, 2021, 72(9): 4685-4697.
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Sample | SBET①/ (m2/g) | Smicro②/ (m2/g) | Smeso②/ (m2/g) | Vtotal③/ (cm3/g) | Vmicro②/ (cm3/g) | Vmeso④/ (cm3/g) | Dmeso/ nm | Crystallinity⑤/ % |
---|---|---|---|---|---|---|---|---|
NaY | 775 | 758 | 17 | 0.38 | 0.31 | 0.07 | 1.91 | 100 |
E-NaY | 620 | 595 | 25 | 0.36 | 0.27 | 0.09 | 1.93 | 24 |
EW-NaY | 628 | 438 | 190 | 0.39 | 0.21 | 0.18 | 3.45 | 32 |
0.2AT-NaY | 718 | 697 | 20 | 0.42 | 0.33 | 0.09 | 1.93 | 92 |
E0.2AT-NaY | 720 | 627 | 93 | 0.53 | 0.29 | 0.24 | 3.59 | 67 |
EW0.2AT-NaY | 670 | 465 | 205 | 0.66 | 0.21 | 0.45 | 3.59 | 52 |
Table 1 Textural properties and relative crystallinity of NaY zeolites
Sample | SBET①/ (m2/g) | Smicro②/ (m2/g) | Smeso②/ (m2/g) | Vtotal③/ (cm3/g) | Vmicro②/ (cm3/g) | Vmeso④/ (cm3/g) | Dmeso/ nm | Crystallinity⑤/ % |
---|---|---|---|---|---|---|---|---|
NaY | 775 | 758 | 17 | 0.38 | 0.31 | 0.07 | 1.91 | 100 |
E-NaY | 620 | 595 | 25 | 0.36 | 0.27 | 0.09 | 1.93 | 24 |
EW-NaY | 628 | 438 | 190 | 0.39 | 0.21 | 0.18 | 3.45 | 32 |
0.2AT-NaY | 718 | 697 | 20 | 0.42 | 0.33 | 0.09 | 1.93 | 92 |
E0.2AT-NaY | 720 | 627 | 93 | 0.53 | 0.29 | 0.24 | 3.59 | 67 |
EW0.2AT-NaY | 670 | 465 | 205 | 0.66 | 0.21 | 0.45 | 3.59 | 52 |
Sample | Relative content of various Si units/% | n (Si)/ n (Al) | |||||
---|---|---|---|---|---|---|---|
Si(4Al) | Si(3Al) | Si(2Al) | Si(1Al) | Si(0Al) | Amorphous Si | ||
NaY | 3.24 | 10.25 | 32.75 | 43.62 | 10.15 | — | 2.30 |
E-NaY | 2.55 | 8.18 | 18.74 | 47.92 | 15.49 | 7.12 | 2.96 |
EW-NaY | 1.95 | 5.33 | 18.24 | 53.14 | 12.06 | 5.98 | 3.17 |
0.2AT-NaY | 5.05 | 14.44 | 35.14 | 37.49 | 7.88 | — | 2.33 |
E0.2AT-NaY | 4.57 | 16.05 | 38.35 | 30.83 | 10.2 | — | 2.35 |
EW0.2AT-NaY | 4.04 | 13.48 | 28.29 | 45.14 | 9.05 | — | 2.54 |
Table 2 Relative content of various Si units and framwork ratio of Si/Al calculated from 29Si MAS NMR spectra
Sample | Relative content of various Si units/% | n (Si)/ n (Al) | |||||
---|---|---|---|---|---|---|---|
Si(4Al) | Si(3Al) | Si(2Al) | Si(1Al) | Si(0Al) | Amorphous Si | ||
NaY | 3.24 | 10.25 | 32.75 | 43.62 | 10.15 | — | 2.30 |
E-NaY | 2.55 | 8.18 | 18.74 | 47.92 | 15.49 | 7.12 | 2.96 |
EW-NaY | 1.95 | 5.33 | 18.24 | 53.14 | 12.06 | 5.98 | 3.17 |
0.2AT-NaY | 5.05 | 14.44 | 35.14 | 37.49 | 7.88 | — | 2.33 |
E0.2AT-NaY | 4.57 | 16.05 | 38.35 | 30.83 | 10.2 | — | 2.35 |
EW0.2AT-NaY | 4.04 | 13.48 | 28.29 | 45.14 | 9.05 | — | 2.54 |
Sample | Acidity/(mmol/g) ① | Acidity/(μmol/g) ② | ||
---|---|---|---|---|
Total | Br?nsted | Lewis | ||
HY | 2.429 | 96 | 71 | |
E-HY | 0.749 | 47 | 65 | |
EW-HY | 0.510 | 54 | 61 | |
0.2AT-HY | 1.946 | 191 | 103 | |
E0.2AT-HY | 1.864 | 176 | 124 | |
EW0.2AT-HY | 1.072 | 66 | 97 |
Table 3 Acidity of HY zeolites
Sample | Acidity/(mmol/g) ① | Acidity/(μmol/g) ② | ||
---|---|---|---|---|
Total | Br?nsted | Lewis | ||
HY | 2.429 | 96 | 71 | |
E-HY | 0.749 | 47 | 65 | |
EW-HY | 0.510 | 54 | 61 | |
0.2AT-HY | 1.946 | 191 | 103 | |
E0.2AT-HY | 1.864 | 176 | 124 | |
EW0.2AT-HY | 1.072 | 66 | 97 |
Catalyst | Peak area | (Cu+/Cusum)/% | |
---|---|---|---|
Cu+ | Cu2+ | ||
CuY | 38508.2 | 14516.7 | 72.6 |
E-CuY | 22944.8 | 7801.4 | 74.6 |
EW-CuY | 27367.8 | 8287.9 | 76.7 |
0.2AT-CuY | 36988.2 | 13005.5 | 73.9 |
E0.2AT-CuY | 42272.8 | 9049.7 | 82.3 |
EW0.2AT-CuY | 45612.5 | 8050.7 | 84.9 |
Table 4 Quantitative analysis of the Cu 2p3/2 XPS curve fitting of CuY catalysts
Catalyst | Peak area | (Cu+/Cusum)/% | |
---|---|---|---|
Cu+ | Cu2+ | ||
CuY | 38508.2 | 14516.7 | 72.6 |
E-CuY | 22944.8 | 7801.4 | 74.6 |
EW-CuY | 27367.8 | 8287.9 | 76.7 |
0.2AT-CuY | 36988.2 | 13005.5 | 73.9 |
E0.2AT-CuY | 42272.8 | 9049.7 | 82.3 |
EW0.2AT-CuY | 45612.5 | 8050.7 | 84.9 |
Catalyst | wCu①/% | CO-Cu+ peak area② | CO-Cu+ peak area/ Br?nsted③ | STYDMC/(mg/(g·h)) | XCH | Selectivity of products/% | |||
---|---|---|---|---|---|---|---|---|---|
DMC | DME | DMM | MF | ||||||
CuY | 5.4 | 2.6 | 0.027 | 75.3 | 2.8 | 49.1 | 3.7 | 39.4 | 7.8 |
E-CuY | 5.8 | 3.9 | 0.082 | 101.7 | 3.2 | 59.4 | 1.3 | 27.2 | 12.1 |
EW-CuY | 5.9 | 4.6 | 0.085 | 131.1 | 4.2 | 61.4 | 1.1 | 23.2 | 14.3 |
0.2AT-CuY | 6.0 | 3.4 | 0.018 | 93.0 | 3.1 | 54.8 | 1.7 | 31.5 | 11.9 |
E0.2AT-CuY | 5.8 | 6.8 | 0.039 | 172.7 | 5.7 | 65.3 | 1.0 | 28.1 | 6.2 |
EW0.2AT-CuY | 5.0 | 5.9 | 0.089 | 166.2 | 5.3 | 65.2 | 1.1 | 27.1 | 6.5 |
Table 5 Catalytic performance of CuY catalysts for oxidative carbonylation of methanol
Catalyst | wCu①/% | CO-Cu+ peak area② | CO-Cu+ peak area/ Br?nsted③ | STYDMC/(mg/(g·h)) | XCH | Selectivity of products/% | |||
---|---|---|---|---|---|---|---|---|---|
DMC | DME | DMM | MF | ||||||
CuY | 5.4 | 2.6 | 0.027 | 75.3 | 2.8 | 49.1 | 3.7 | 39.4 | 7.8 |
E-CuY | 5.8 | 3.9 | 0.082 | 101.7 | 3.2 | 59.4 | 1.3 | 27.2 | 12.1 |
EW-CuY | 5.9 | 4.6 | 0.085 | 131.1 | 4.2 | 61.4 | 1.1 | 23.2 | 14.3 |
0.2AT-CuY | 6.0 | 3.4 | 0.018 | 93.0 | 3.1 | 54.8 | 1.7 | 31.5 | 11.9 |
E0.2AT-CuY | 5.8 | 6.8 | 0.039 | 172.7 | 5.7 | 65.3 | 1.0 | 28.1 | 6.2 |
EW0.2AT-CuY | 5.0 | 5.9 | 0.089 | 166.2 | 5.3 | 65.2 | 1.1 | 27.1 | 6.5 |
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