Biochar-assisted purification of wood vinegar derived from coconut shell pyrolysis

Abstract

Wood vinegar, also known as pyroligneous acid, is a liquid byproduct obtained from the process of slow pyrolysis of biomass [1]. Slow pyrolysis involves the thermal decomposition of organic materials at temperatures typically ranging between 300°C and 800°C in the absence of oxygen, which results in the production of biochar, syngas and wood vinegar [2]. The primary feedstocks for wood vinegar production include various types of biomasses such as hardwood, softwood and agricultural residues [3]. During slow pyrolysis, biomass undergoes a series of complex chemical reactions, leading to the formation of condensable vapors and non-condensable gases. The condensable vapors, when cooled, form a liquid mixture comprising water, acetic acid, methanol, acetone, and a variety of phenolic compounds [2]. This liquid mixture is known as wood vinegar. The composition of wood vinegar can vary significantly depending on the type of feedstock, pyrolysis temperature, and pyrolysis duration [4].