Hydrochar production from watermelon peel by hydrothermal carbonization

Xuejiao Chen; Qimei Lin; Ruidong He; Xiaorong Zhao; Guitong Li

doi:10.1016/j.biortech.2017.04.012

Hydrochar production from watermelon peel by hydrothermal carbonization

Bioresour Technol. 2017 Oct:241:236-243. doi: 10.1016/j.biortech.2017.04.012. Epub 2017 Apr 8.

Authors

Xuejiao Chen¹, Qimei Lin², Ruidong He¹, Xiaorong Zhao¹, Guitong Li¹

Affiliations

¹ Department of Soil and Water Science, College of Resources and Environment, China Agricultural University, Beijing 100193, China.
² Department of Soil and Water Science, College of Resources and Environment, China Agricultural University, Beijing 100193, China. Electronic address: linqm@cau.edu.cn.

PMID: 28570889
DOI: 10.1016/j.biortech.2017.04.012

Abstract

Watermelon peel waste was hydrothermally carbonized under 190°C and 260°C for 1h, 6h, and 12h, respectively. The hydrochar and spent liquor were collected and assayed for their properties. The results indicated that hydrochar yield was 2-5% and 46-95% on fresh and dry matter, respectively. Low temperature (190°C) was conducive to high conversion efficiency. The hydrochar had higher C/N ratio (22.19-26.86), more alkyl C, aryl C, and carbonyl C, but lower H/C (0.98-1.22) and O/C ratios (0.13-0.38), and less O-alky C, carboxylic C, compared with feedstock. So the aliphaticity decreased, whereas aromaticity increased significantly, especially under severe conditions. It should be watchful for that the toxic compounds in hydrochar may induce environmental risk while it is amended into soil. The spent liquor with abundant nutrients could be used as a fertilizer. Further work is required for testing the application in soil.

Keywords: Hydrochar; Hydrothermal carbonization; Spent liquor; Watermelon peel.

MeSH terms

Biofuels
Carbon*
Citrullus*
Soil

Substances

Biofuels
Soil
Carbon