Kinetics and Mechanisms of Metal Chlorides Catalysis for Coal Char Gasification with CO<sub>2</sub>
The gasification experiments of coal chars with CO<sub>2</sub> were carried out isothermally, with K, Ca, Ni, and Zn chloride catalysts, adopting a thermal gravimetric analyzer (TGA) from 800 to 1100 °C. The kinetic characteristic of the samples were described using the volumetric model...
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MDPI AG
2020-06-01
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| Series: | Catalysts |
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| Online Access: | https://www.mdpi.com/2073-4344/10/6/715 |
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| author | Yong He Ye Yuan Zhihua Wang Longlong Liu Jiaxin Tan Jiahao Chen Kefa Cen |
| author_facet | Yong He Ye Yuan Zhihua Wang Longlong Liu Jiaxin Tan Jiahao Chen Kefa Cen |
| author_sort | Yong He |
| collection | DOAJ |
| description | The gasification experiments of coal chars with CO<sub>2</sub> were carried out isothermally, with K, Ca, Ni, and Zn chloride catalysts, adopting a thermal gravimetric analyzer (TGA) from 800 to 1100 °C. The kinetic characteristic of the samples were described using the volumetric model (VM), the grain model (GM), and the random pore model (PRM). The morphology patterns of the samples were tested applying X-ray diffraction (XRD) and the catalytic mechanisms concerning the phase changes were proposed. The results confirm that the gasification rate and char reactivities are enhanced by K, Ca and Ni chlorides, while ZnCl<sub>2</sub> inhibited the process. The catalysis ability shows the following cation order: Ca > K > Ni > Zn. Among the models described above, PRM was proven to give the best fitting value and hence adopted to kinetics parameters calculation. The activation energies in promoting conditions were lower than that of the uncatalyzed cases. In view of the catalytic mechanism, the K metals tend to form intermediate complexes and repeatedly connect with coal char, while the Ca species may follow the oxidation-reduction mechanism and the Ni metals catalyze the gasification process. |
| first_indexed | 2024-03-10T18:52:28Z |
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| id | doaj.art-88dc450d94624ab0bcbbc9378c787343 |
| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-10T18:52:28Z |
| publishDate | 2020-06-01 |
| publisher | MDPI AG |
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| series | Catalysts |
| spelling | doaj.art-88dc450d94624ab0bcbbc9378c7873432023-11-20T05:02:44ZengMDPI AGCatalysts2073-43442020-06-0110671510.3390/catal10060715Kinetics and Mechanisms of Metal Chlorides Catalysis for Coal Char Gasification with CO<sub>2</sub>Yong He0Ye Yuan1Zhihua Wang2Longlong Liu3Jiaxin Tan4Jiahao Chen5Kefa Cen6State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, ChinaState Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, ChinaState Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, ChinaState Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, ChinaState Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, ChinaState Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, ChinaState Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, ChinaThe gasification experiments of coal chars with CO<sub>2</sub> were carried out isothermally, with K, Ca, Ni, and Zn chloride catalysts, adopting a thermal gravimetric analyzer (TGA) from 800 to 1100 °C. The kinetic characteristic of the samples were described using the volumetric model (VM), the grain model (GM), and the random pore model (PRM). The morphology patterns of the samples were tested applying X-ray diffraction (XRD) and the catalytic mechanisms concerning the phase changes were proposed. The results confirm that the gasification rate and char reactivities are enhanced by K, Ca and Ni chlorides, while ZnCl<sub>2</sub> inhibited the process. The catalysis ability shows the following cation order: Ca > K > Ni > Zn. Among the models described above, PRM was proven to give the best fitting value and hence adopted to kinetics parameters calculation. The activation energies in promoting conditions were lower than that of the uncatalyzed cases. In view of the catalytic mechanism, the K metals tend to form intermediate complexes and repeatedly connect with coal char, while the Ca species may follow the oxidation-reduction mechanism and the Ni metals catalyze the gasification process.https://www.mdpi.com/2073-4344/10/6/715char gasificationcatalytic kineticscatalytic mechanismsmetal chlorides |
| spellingShingle | Yong He Ye Yuan Zhihua Wang Longlong Liu Jiaxin Tan Jiahao Chen Kefa Cen Kinetics and Mechanisms of Metal Chlorides Catalysis for Coal Char Gasification with CO<sub>2</sub> Catalysts char gasification catalytic kinetics catalytic mechanisms metal chlorides |
| title | Kinetics and Mechanisms of Metal Chlorides Catalysis for Coal Char Gasification with CO<sub>2</sub> |
| title_full | Kinetics and Mechanisms of Metal Chlorides Catalysis for Coal Char Gasification with CO<sub>2</sub> |
| title_fullStr | Kinetics and Mechanisms of Metal Chlorides Catalysis for Coal Char Gasification with CO<sub>2</sub> |
| title_full_unstemmed | Kinetics and Mechanisms of Metal Chlorides Catalysis for Coal Char Gasification with CO<sub>2</sub> |
| title_short | Kinetics and Mechanisms of Metal Chlorides Catalysis for Coal Char Gasification with CO<sub>2</sub> |
| title_sort | kinetics and mechanisms of metal chlorides catalysis for coal char gasification with co sub 2 sub |
| topic | char gasification catalytic kinetics catalytic mechanisms metal chlorides |
| url | https://www.mdpi.com/2073-4344/10/6/715 |
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