Conversion of carbon monoxide in supercritical water and the influence of alkaline potassium salts

DING Qi-zhong; ZHANG Jun; ZHAO Liang; LU Qi-an

Volume 47 Issue 8

Aug. 2019

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Article Navigation > Journal of Fuel Chemistry and Technology > 2019 > 47(8): 980-986

DING Qi-zhong, ZHANG Jun, ZHAO Liang, LU Qi-an. Conversion of carbon monoxide in supercritical water and the influence of alkaline potassium salts[J]. Journal of Fuel Chemistry and Technology, 2019, 47(8): 980-986.

Citation:

DING Qi-zhong, ZHANG Jun, ZHAO Liang, LU Qi-an. Conversion of carbon monoxide in supercritical water and the influence of alkaline potassium salts[J]. Journal of Fuel Chemistry and Technology, 2019, 47(8): 980-986.

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Conversion of carbon monoxide in supercritical water and the influence of alkaline potassium salts

1.
Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, Southeast University, Nanjing 210096, China;
2.
School of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China

Funds:

the National Natural Science Foundation of China 51606103

Open Fund of Key Laboratory of Efficient & Clean Energy Utilization of Hunan Provincial Education Department, China 2017NGQ005

Open Fund of Innovation Platform of Hunan Provincial Education Department, China 17K002

More Information

Corresponding author: ZHANG Jun, E-mail: junzhang@seu.edu.cn
Received Date: 2019-04-22
Rev Recd Date: 2019-06-17

Available Online: 2021-01-23

Publish Date: 2019-08-10

Abstract

Abstract

The conversion of carbon monoxide in supercritical water was investigated in a continuous reaction system which could dissolve carbon monoxide in water at high pressure. Meanwhile, due to the diversity of potassium salts in biomass supercritical water gasification, the influence of various alkaline potassium salts (KHCO₃, K₂CO₃ and KOH) on the water gas shift reaction were investigated at 450-600 ℃, 23-29 MPa and with a residence time of 3-6 s. The results show that under non-catalytic conditions, the increases in reaction temperature and residence time both lead to higher CO conversion. The effect of pressure on CO conversion is distinct at low pressure (23-25 MPa), but rather minor at higher pressure (25-29 MPa). The rate expression for the non-catalytic water gas shift reaction is k=10^3.75×exp(-0.66×10⁵/RT)(s^-1). The potassium salts can promote the CO conversion significantly and the activity of three salts follows the order of KHCO₃ > K₂CO₃ > KOH; the conversion of CO is enhanced at higher temperature and longer reaction time, whereas the effect of pressure on CO conversion is much complicated. The catalytic effect of alkaline potassium salts in the CO conversion may be explained by the formation of oxalate (HC₂O₄^-) and formate (HCOO^-) intermediates.
- alkaline potassium salts,
- water gas shift,
- supercritical water,
- CO conversion

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References(18)

References

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