Inducing hour-level humification of Enteromorpha prolifera to fabricate fulvic-like acid fertilizer with Fenton’s reagent
Dongqing Cai, Yezhen Lu, Yanping Zhu, Dongfang Wang, Jiping Shi, Li Liu, Jianyong Li, Xiuping Zhan, Weijian Zhang, He Xu
Abstract
The phenomenon of Enteromorpha prolifera (EP) flooding caused by marine eutrophication has resulted in serious environmental impact. Here, we demonstrate an application of Fenton’s reagent in the rapid recovery and utilization of EP. The humification of EP with water content of 80–90% is accelerated by adding H2O2 and FeSO4·7H2O. A notable self-heating phenomenon (from 22 to 86 °C) is observed within 10 min, and the sample is dried to obtain the EP fertilizer (EPF) after 60 min, which contained 25.5 ± 4.3% (wt%) of fulvic-like acid (FLA). Aromatization, amidation and carboxylation reactions induced by free radicals (mainly •OH) play a key role in EP (mainly polysaccharides and proteins) humification through degradation-polymerization pathway. A scale-up experiment is also carried out to confirm the feasibility of this technology. EPF increases the fresh weight of chickweeds (pot experiment) and cabbage (field plot experiment) by 27.1% and 609.7% compared with blank, respectively. This study opens a promising avenue for application of Fenton reaction in biowaste humification, which is beneficial for efficient EP recycling and agriculture sustainable development. The phenomenon of Enteromorpha prolifera (EP) flooding caused by marine eutrophication has resulted in serious environmental impact. Here, the authors demonstrate an application of Fenton’s reagent in the rapid recovery and utilization of EP.