Hydrogen-rich syngas production by gasification of Urea-formaldehyde plastics in supercritical water. (14th October 2021)

• Record Type: Journal Article
• Authors: Wang, Weizuo; Bai, Bin; Wei, Wenwen; Cao, Changqing; Jin, Hui
• Is Part Of: International journal of hydrogen energy. Volume 46:Number 71(2021)
• Page Start: 35121
• Page End: 35129
• Publication Date: 2021-10-14
• Subjects: Supercritical water gasification -- Hydrogen production -- Urea-formaldehyde plastics -- Kinetic; UF urea-formaldehyde -- PS polystyrene -- CFP catalytic fast pyrolysis -- CCP catalytic co-pyrolysis -- SCWG supercritical water gasification -- CE carbon gasification efficiency -- HE hydrogen gasification efficiency -- WGS water gas shift reaction; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2021.08.072
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Supercritical water is a promising medium to convert plastics into hydrogen and other recyclable products efficiently. In previous research, supercritical water gasification characteristics investigations focus on thermoplastics instead of thermoset plastics due to its chemical, thermal and mechanical stability. Urea-formaldehyde (UF) plastics were selected as a typical kind of thermoset plastics for investigation in this paper and quartz tubes were used as the reactor in order to avoid the potential catalytic effect of metal reactor wall. Conversion characteristic were studied and the influence of different operating parameters such as temperature, reaction time, feedstock mass fraction and pressure were investigated respectively. The molar fraction of hydrogen could reach about 70% in 700 °C. Products in gas phase and solid phase were analyzed, and properties, chemical structures and inhibition mechanism of thermoset plastics was analyzed after comparing with polystyrene (PS) plastics. The result showed that increase of high temperature and long reaction time could promote gasification process, meanwhile the increase in the feedstock mass fraction would result in suppression of the gasification process. Finally, kinetic study of UF was carried out and the activation energy and pre-exponential factor of the Arrhenius equation were calculated as 30.09 ± 1.62 kJ/mol and 0.1199 ± 0.0049 min −1, respectively. Highlights: Thermoset plastics were firstly gasified in supercritical water. Kinetic was studied and the third-order model was used. Factors affecting gasification efficiency were investigated. Activation energy and pre-exponential factor were 30.09 kJ/mol and 0.1199 min −1 .