Iranian Research Organization for Science and Technology Advances in Environmental Technology 2476-6674 8 1 2022 02 01 Ammonium-nitrogen removal from aqueous solution using municipal green waste wood biochars 15 29 1131 10.22104/aet.2022.5087.1379 EN Wilson E. Ndibize Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing, China National Center for International Research of Low-carbon and Green Buildings (Ministry of Science and Technology), Chongqing University, Chongqing, China School of Environment and Ecology, Chongqing University, Chongqing, China Md Nuralam Hossain Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing, China National Center for International Research of Low-carbon and Green Buildings (Ministry of Science and Technology), Chongqing University, Chongqing, China School of Environment and Ecology, Chongqing University, Chongqing, China 0000-0003-0029-9367 Nan Hongyan Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing, China School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China Muhammad Salam Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing, China National Center for International Research of Low-carbon and Green Buildings (Ministry of Science and Technology), Chongqing University, Chongqing, China School of Environment and Ecology, Chongqing University, Chongqing, China Md. Manik Mian CAS Key Laboratory of Crust-Mantle Materials and the Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, China 0000-0002-1947-6872 Md. Eusuf Sarker Department of Environmental Science and Resource Management, Mawlana Bhashani Science and Technology University, Santosh, Tangail, Bangladesh Md. Rokebul Islam Shojib Department of Mechanical Engineering, Chongqing University, Chongqing, China Journal Article 2021 11 13 Ammonium (NH₄⁺), one of the most common types of reactive form of nitrogen in wastewater, can cause eutrophication and other environmental problems if released into waterways. This study was conducted to understand NH₄⁺ adsorption mechanism of wood biochar from municipal green waste in an aqueous environment and the factors affecting NH₄⁺ removal. The biochars were produced by pyrolyzing green wood waste at 300°C (WB300), 450°C (WB400), and 600°C (WB600), respectively. Biochar dosage, pH, and contact duration were studied during NH₄⁺ adsorption studies to see how these variables affected the adsorption process. The adsorption process was studied using isotherms and kinetic adsorption models. The batch equilibrium and kinetic studies at 25°C, pH 7, and a contact duration of 240 minutes showed that the WB450 dosage of 0.2 g/L removed the most (NH₄⁺-N) compared to WB600 and WB300. WB450 had higher affinity values and a maximum adsorption capacity of 2.34 mg/g; the ‘Freundlich isotherm’ model had a better fit to the equilibrium experimental data, indicating that heterogeneous sorption was preferable to monolayer sorption. Chemisorption was the dominant (NH₄⁺) adsorption method, as demonstrated by the ‘pseudo-second-order’ kinetic model with an R² of 0.99. The study concludes that municipal green wood waste-based biochar can be efficient absorbents for NH₄⁺ removal from wastewater. Also, the removal efficiency can be optimized by selecting different feedstocks or the pyrolysis condition for biochar production. https://aet.irost.ir/article_1131_fe709c654eac84d5239d1a12a4f71877.pdf