The effect of pyrolysis temperature and ball-milling duration on characteristics of micro bio-char derived from oil palm empty fruit bunches

Abstract

Oil palm empty fruit bunch is a solid waste that accounts for 22% of palm oil production, but its utilization is still limited, so it needs further processing. One alternative for processing oil palm empty fruit bunch waste is using pyrolysis to produce biochar and syngas. The present research worked on producing micro biochar to increase the surface area by making smaller particles. Oil palm empty fruit can be converted into micro biochar with a ball mill. This study aimed to determine the effect of pyrolysis temperature and ball mill duration on the proximate characteristics and particle size distribution of oil palm empty fruit bunch micro-biochar. The research design was arranged using a Randomised Block Design with two factors: pyrolysis temperature (400°C, 500°C, and 600°C) and ball mill time (24 hours, 48 hours, and 72 hours). The micro biochar characterisation includes moisture content, ash content, bound carbon content (bound carbon), volatile matter, calorific value, and particle size distribution. The results showed that pyrolysis temperature and ball mill duration had an insignificant effect on water content. The heating value increased with increasing pyrolysis temperature. The carbon content slightly increased with pyrolysis temperature and ball mill duration. The temperature and duration of the ball milling influenced the particle size distribution. The higher the pyrolysis temperature and the ball mill duration, the smaller the average particle size distribution. The smallest particle size was 3.04 µm, pyrolyzed at 600°C and had a ball milling duration of 72 hours.