Microwave Assisted Pyrolysis of Moringa Seed and Karanja for Bio-Oil Production

Abstract

Microwave-assisted pyrolysis is an alternative technique of conventional heating which undergo thermochemical process to convert biomass to bio oil, bio char and biogas. Microwave-assisted pyrolysis is more rapid and efficient to produce product compared to conventional heating. A modified household microwave oven with 800W was used to pyrolyze Moringa seed and Karanja to become bio oil and bio char. This experiment was repeated in different parameters such as time, temperature and power to obtain maximum bio oil yield. Bio oil yield of Moringa seed increased from 7.2 wt% at 300°C in 5 minutes to 10.6 wt% at 450°C in 13 minutes. Bio oil of both raw materials showed maximum yield when pyrolysis time is 13 minutes in 800W but after 13 minutes, the bio oil yield of Moringa decrease of 2.4% and bio oil yield of Karanja decrease of 4.7%. The calorific value of Moringa bio oil is 25.08MJ/kg whereas Karanja bio oil is 20.36 MJ/kg. Functional group of both bio oil mainly include alcohol, ketones, aldehydes and carboxylic acid. The pH value of Moringa bio oil and Karanja bio oil are 4.38 and 5.86 respectively.

Keywords: Microwave-assisted pyrolysis, bio-oil, bio char, moringa seed, karanja.