Catalytic Pyrolysis of Naomaohu Coal Using Combined CaO and Ni/Olivine Catalysts for Simultaneously Improving the Tar and Gas Quality

Yalkunjan Tursun (), Ke Wang, Runxiao Yi, Hairat Abduhani, Zhenghua Dai, Mei Zhong, Lijun Jin, Jian Li and Yang Liu
Additional contact information
Yalkunjan Tursun: State Key Laboratory of Chemistry and Utilization of Carbon-Based Energy Resource, Xinjiang University, Urumqi 830017, China
Ke Wang: State Key Laboratory of Chemistry and Utilization of Carbon-Based Energy Resource, Xinjiang University, Urumqi 830017, China
Runxiao Yi: State Key Laboratory of Chemistry and Utilization of Carbon-Based Energy Resource, Xinjiang University, Urumqi 830017, China
Hairat Abduhani: State Key Laboratory of Chemistry and Utilization of Carbon-Based Energy Resource, Xinjiang University, Urumqi 830017, China
Zhenghua Dai: State Key Laboratory of Chemistry and Utilization of Carbon-Based Energy Resource, Xinjiang University, Urumqi 830017, China
Mei Zhong: State Key Laboratory of Chemistry and Utilization of Carbon-Based Energy Resource, Xinjiang University, Urumqi 830017, China
Lijun Jin: State Key Laboratory of Chemistry and Utilization of Carbon-Based Energy Resource, Xinjiang University, Urumqi 830017, China
Jian Li: State Key Laboratory of Chemistry and Utilization of Carbon-Based Energy Resource, Xinjiang University, Urumqi 830017, China
Yang Liu: State Key Laboratory of Chemistry and Utilization of Carbon-Based Energy Resource, Xinjiang University, Urumqi 830017, China

Energies, 2024, vol. 17, issue 7, 1-14

Abstract: Catalytic pyrolysis of low-rank coal is currently an effective method for producing high-quality tar and gas. In this study, catalytic upgrading of volatiles from Naomaohu (NMH) coal pyrolysis has been conducted in a two-stage fixed-bed reactor using combined CaO and Ni/olivine (Ni-loaded olivine) catalysts. The effect of catalyst distribution modes and catalytic temperature on the tar and gas quality has been investigated. Simulated distillation and GC-MS analysis have been used to investigate the distribution of tar components. The results indicated that the light oil fraction in tar dramatically increased due to the combination of CaO and Ni/olivine. The CaO-Ni/olivine mode is especially better compared to the layouts of the Ni/olivine-CaO mode and the mixed mode. The CaO-Ni/olivine mode ensures a higher light fraction in tar at 69.3% and a light oil fraction at 29.8% at a catalytic temperature of 450 °C, while the heavy tar fraction decreased to 30.7%. Meanwhile, the contents of benzene (heteroatomic substituents) in tar significantly increased from 2.55% to 6.45% compared with the blank test. In this scenario, CaO breaks down macromolecular compounds in tar and cleaves long-chain esters to produce aliphatic hydrocarbons. These hydrocarbons are then dehydrogenated to produce lighter aromatic hydrocarbons over the CaO surface. Subsequently, the volatiles pass through the Ni/olivine catalysis, where ether compounds are produced by means of dehydration reactions. In addition, the CaO absorbs the CO 2 in the pyrolysis gas, leading to an elevation of CH 4 and H 2 concentration. Particularly, the concentration of H 2 significantly increased from 16.2% to 30.37%, while the concentration of CO 2 significantly decreased from 37.9% to 10.57%. These findings suggest that the usage of combined CaO and Ni/olivine catalysts is beneficial for improving both the tar and gas quality.

Keywords: CaO; Naomaohu coal pyrolysis; volatile upgrading; Ni/olivine (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2024
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/17/7/1613/pdf (application/pdf)
https://www.mdpi.com/1996-1073/17/7/1613/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:17:y:2024:i:7:p:1613-:d:1365589

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().