J. Eng. Technol. Sci., Vol. 54, No. 1, 2022, 220108 Received March 11 th , 2021, Revised May 2 nd , 2021, Accepted for publication August 17 th , 2021. Copyright ©2022 Published by ITB Institute for Research and Community Services, ISSN: 2337-5779, DOI: 10.5614/j.eng.technol.sci.2022.54.1.8 Volatile State Mathematical Models for Predicting Components in Biomass Pyrolysis Products Pandit Hernowo 1,2 , Carolus B. Rasrendra 1,3 , Yogi W. Budhi 1 , Jenny Rizkiana 1,3 , Anton Irawan 4 , Septhian Marno 5 , Yana Meliana 5 , Oki Muraza 6 & Yazid Bindar 1,3,* 1 Department of Chemical Engineering, Faculty of Industrial Technology, Institut Teknologi Bandung, Jalan Ganesa No. 10 Bandung 40132, Indonesia 2 Department of Chemical Engineering, Institut Sains dan Teknologi Al-Kamal, Jalan Raya Al-Kamal No. 2, Kedoya, Jakarta Barat 11520, Indonesia 3 Department of Bioenergy Engineering and Chemurgy, Faculty of Industrial Technology, Institut Teknologi Bandung, Jalan Ganesa No. 10 Bandung 40132, Indonesia 4 Department of Chemical Engineering, Engineering Faculty, University of Sultan Ageng Tirtayasa, Banten 42435, Indonesia 5 Research and Technology Centre Pertamina, PT. Pertamina, Jalan Raya Bekasi No. 20, Pulau Gadung, Jakarta Timur, Indonesia 6 Research & Technology Innovation, Pertamina Sopo Del Building, 51 st Fl. Jalan Mega Kuningan Barat III, Jakarta Pusat, Indonesia *E-mail: ybybyb@fti.itb.ac.id Highlights:  New equation models were developed to predict pyrolysis product compositions.  The models introduce biomass type numbers and pseudo activation energy.  The component pseudo activation energy is temperature dependent.  45 components in the biomass pyrolysis products were well predicted using the models. Abstract. Volatile state mathematical models for quantifying the chemical components in volatile biomass pyrolysis products were developed. The component mass yield Yi rate depends linearly on its pseudo kinetic constant and the remaining mass yield. The mass fraction rate of each component was modeled from the derivation of its mass yield rate equation. A new mathematical model equation was successfully developed. The involved variables are: biomass number, temperature, heating rate, pre-exponential factor, and pseudo activation energy related to each component. The component mass fraction yi and the mass yield were predicted using this model within a temperature range. Available experimental pyrolysis data for beechwood and rice husk biomass were used to confirm the developed model. The volatile products were separated into bio- pyrolysis gas (BPG) and a bio-pyrolysis oil (BPO). Five components in the BPG and forty in the BPO were quantified. The pseudo activation energy for each pseudo chemical reaction for a specific component was modeled as a polynomial