Pyrolysis of mango seeds in a fixed-bed reactor for production of bio-oil as an alternative fuel

• Pyrolysis of mango seed, shell, and kernel to produce bio-oil. • Low-grade waste biomass replaces electricity for sustainable reactor heating. • Feedstock evaluated in full, half, and quarter sizes for yield optimization. • Maximum bio-oil yield achieved with quarter-sized feed at 250±10 °C. • Produced bio-oils show potential as an alternative fuel or blend for fossil fuels. Exploring new and sustainable energy sources is becoming increasingly essential due to obstacles in oil and gas extraction, rising fuel prices, and the increasing global energy demand driven by population growth. This study investigates the pyrolysis of mango seed, shell, and kernel for producing bio-oil in a fixed-bed external heating reactor utilizing low-grade waste biomass for heating instead of electricity. The study aimed to explore the effects of various operating conditions, such as temperature, feed size, and operating time on product yields to identify optimal conditions and assess the project's economic feasibility. The experiments were conducted at temperatures ranging from 150 to 350 °C using full, half, and quarter-sized feedstock. The maximum production of bio-oil from mango seed, shell, and kernel are 33.84 wt.%, 36.37 wt.%, and 35.06 wt.%, respectively, at an optimum temperature of 250±10 °C with the quarter-sized sample. The resulting bio-oil exhibited densities of 855 to 918 kg/m 3 , viscosities of 2.50 to 3.78 cSt, flash points of 100 to 125 °C, and pour points of – 9 to – 14 °C. However, despite these promising attributes, the energy content was relatively low, with a gross calorific value of 16 to 21 MJ/kg. The FTIR analysis revealed the existence of several functional groups, including alkanes, alkenes, aldehydes, ketones, carboxylic acids, esters, and others. The findings suggest the potential of bio-oil produced from mango seed, shell, and kernel as a low-grade alternative fuel or blend for fossil fuels, contributing to the reduction of environmental pollution.