Persulfate assisted hydrothermal processing of spirulina for enhanced deoxidation carbonization

Tengfei Wang; Xiangmin Liu; Dongmei Wang; Zhengjun Gong; Buchun Si; Yunbo Zhai

doi:10.1016/j.biortech.2020.124543

Persulfate assisted hydrothermal processing of spirulina for enhanced deoxidation carbonization

Bioresour Technol. 2021 Feb:322:124543. doi: 10.1016/j.biortech.2020.124543. Epub 2020 Dec 15.

Authors

Tengfei Wang¹, Xiangmin Liu², Dongmei Wang³, Zhengjun Gong⁴, Buchun Si⁵, Yunbo Zhai²

Affiliations

¹ Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 611756, China. Electronic address: wtfgxp@163.com.
² College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
³ Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 611756, China.
⁴ Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 611756, China. Electronic address: gongzhengjun@126.com.
⁵ Laboratory of Environment-Enhancing Energy (E2E), Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture, College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China.

PMID: 33348116
DOI: 10.1016/j.biortech.2020.124543

Abstract

The influence of persulfate assisted hydrothermal carbonization (HTC) (160 °C-220 °C) of spirulina and hydrochar properties was assessed. The elementary composition and proximate analysis of hydrochar were investigated on the carbonization degree and basic fuel properties, and the surface functional groups and morphological characteristics of hydrochar were analyzed as well as thermal stability. Results suggested that persulfate assisted process enhanced the carbonization degree of hydrochar by oxygen reduction (1.53%-2.74%) and increase of C ratio, and HHVs increased 0.81-1.39 MJ/kg at temperature above 180 °C. The -OH and CO on hydrochar surface were significantly reduced, and C-(C, H) and C-(O, N) were weakened by persulfate addition and more C-H peaks was formed. Additionally, the persulfate addition enhanced the thermal stability of hydrochar by lowing the maximum mass loss rate. The result suggested that HTC can be conducted with persulfate at lower temperature for hydrochar biofuel production.

Keywords: Carbon; Carbonization; Hydrochar; Hydrothermal processing; Persulfate; Spirulina.

MeSH terms

Biofuels
Carbon
Spirulina*
Temperature

Substances

Biofuels
Carbon