THE POTENTIAL OF OLIVE POMACE BIOCHAR FOR METAL RETENTION

Abstract

This paper is a review of the potential of olive pomace, a by-product of the olive sector, as a precursor for the production of biochar. In general, it presents a panorama of this sector, which is so important worldwide and particularly in the Mediterranean region, the largest olive and olive oil producing area in the world, representing 90% of global production. We also address the problem of the large amount of waste (around 15 million tons/year), in the form of pomace, generated by this olive oil production industry, which has an impact on the environment and directly on the people living near the plants that process this by-product. Next, we explore the possibility of valorising this by-product, which in the quantities it is produced is even an environmental problem, by transforming it into biochar and revisit the main processes for producing this carbon material. We then focus on the potential for its application in metal retention (e.g. silver, arsenic), through the adsorption process, with a wide range of applications in areas ranging from mining to water treatment and environmental remediation, among others. This section presents the results that show the potential of valorising olive pomace by transforming it into a carbon material, biochar, with a developed porous structure and surface chemistry, which can be adjusted for its specific application in the retention or removal of metals present in liquid phase systems.