Two-step hydrothermal conversion of biomass waste to humic acid using hydrochar as intermediate  

作　　者：Yuchao Shao Jun Zhao Yuyang Long Wenjing Lu 

机构地区：[1]School of Environment,Tsinghua University,Beijing 100084,China [2]Department of Biology,Institute of Bioresource and Agriculture,Hong Kong Baptist University,Hong Kong 999077,China [3]Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling,Instrumental Analysis Center,School of Environmental Science and Engineering,Zhejiang Gongshang University,Hangzhou 310012,China

出　　处：《Frontiers of Environmental Science & Engineering》2023年第10期17-26,共10页环境科学与工程前沿（英文）

基　　金：supported by the Key R&D Program of Ningxia Hui Autonomous Region(China)(No.2020BFG02001);The authors are thankful to Hong Kong Environment Conversion Fund(China)(No.46/2020).

摘　　要：Converting biomass materials to humic acid is a sustainable method for humic acid production and achieve biomass valorization. A two-step hydrothermal treatment method was adopted in this study to produce humic acid from corn stalks. In the first step of the process, hydrochar was prepared at different hydrothermal temperatures and pH values. Their chemical properties were then analyzed, and the hydrochar-derived humic acids were produced under alkaline hydrothermal conditions (denoted as HHAalk). The hydrochar, prepared under high temperature (200 °C) and strong acidic (pH 0) conditions, achieved high HHAalk yields (i.e., 67.9 wt% and 68.8 wt% calculated based on weight of hydrochar). The sources of HHAalk formation were as follows: 1) production in the hydrochar preparation stage, and 2) increment under the alkaline hydrothermal treatment of hydrochar. The degree of hydrochar unsaturation was suggested as an indicator for evaluating the hydrochar humification potential under alkaline hydrothermal conditions. This study provides an important reference for the preparation of suitable hydrochar with high hydrothermal humification potential.

关 键 词：BIOWASTE Hydrochar Humic acid Hydrothermal parameter UNSATURATION 

分 类 号：O62[理学—有机化学]