Thermal Decomposition and Kinetic Study of Agricultural Waste Biomass for Biochar Production Using DTG Analysis
Hendrix Yulis Setyawan1*, Tantrisya Bintang Winahara1, Dodyk Pranowo1, Devy Ulandary1, Yang Zhang2, Arpita Roi3, Mingming Zhu4, Zhijian Wan5, Fasa Aditya Hanindipto6, Juwita Ratna Dewi7, Luluk Mamluhah8

1. Department of Agroindustrial Technology, Faculty of Agricultural Technology, Universitas Brawijaya, Malang, 65145 Indonesia
2. 202 Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China
3. Department of Biotechnology, Sharda School of Bioscience & Technology, Sharda University, Greater Noida, 201310, India
4. School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire, MK43 0AL, UK
5. Energy Business Unit, Commonwealth Scientific Industrial Research Organisation (CSIRO), Kensington, Western Australia 6151, Australia
6. Indonesia Fertilizer Research Institute, Gedung Pusri Jl. Taman Anggrek, Kemanggisan Jaya, Jakarta 11480 - Indonesia
7. Postgraduate School, Environmental Sciences, Universitas Brawijaya, Veteran St, Malang, East Java 65145, Indonesia
8. Integrated Laboratory, Universitas Brawijaya Veteran St, Malang, East Java, Indonesia
*Email : hendrix[at]ub.ac.id

Abstract

Pyrolysis is a thermochemical process that converts biomass into gaseous, liquid, and solid products, with biochar as the primary solid fraction. The thermal behavior of biomass varies considerably among feedstocks, necessitating tailored approaches to optimize product yield and quality. This study investigated the thermal degradation and chemical characteristics of rice husk, sugarcane bagasse, and corn cobs using thermogravimetric analysis (TGA) and differential thermal gravimetry (DTG). A randomized block design with two factors, biomass type and pretreatment (drying vs. untreated), was applied, yielding 18 experimental units. Proximate analysis and pH measurements complemented the thermal characterization to provide a comprehensive profile of each feedstock and its resulting biochar. Results showed that drying pretreatment significantly affected moisture, ash, volatile matter, fixed carbon, and pH, thereby improving sample consistency for thermal analysis. Reproducibility across replicates confirmed the reliability of TGA-DTG data. Among the tested biomasses, sugarcane bagasse exhibited the most favorable thermal profile, with the lowest decomposition onset temperature and shortest reaction duration across pyrolysis stages. Kinetic modeling using the Ozawa-Flynn-Wall (OFW) and Kissinger-Akahira-Sunose (KAS) methods revealed that sugarcane bagasse achieved the highest activation energy values, establishing strong correlations between kinetic parameters and thermal decomposition behavior. Overall, this study demonstrates that DTG-based thermal analysis provides a robust framework for identifying suitable biomass feedstocks and optimizing pyrolysis conditions. Sugarcane bagasse, in particular, emerged as a promising material for producing high-quality biochar with efficient thermal conversion characteristics.

Keywords: Biomass- Biochar- Differential Thermal Gravimetry- Pyrolysis- Thermogravimetric Analysis

Topic: Renewable energy and biorefinery