Sustainable Production of Medium-Chain Fatty Acids from Fresh Leachates in the District of Abidjan: Study of the Feasibility of the Process and Environmental Benefits

Leachate management remains a major environmental challenge, especially in rapidly urbanizing cities of developing countries. Traditionally considered toxic and useless, it is a sustainable organic resource with the potential for high-value biochemical production through bioprocessing. This study investigated the characteristics of fresh leachates from three solid waste transfer stations (SWTS) in the Abidjan district, Côte d’Ivoire, and assessed their potential as substrates for medium-chain fatty acid (MCFA) production via microbial chain elongation. The MCFA synthesis was carried out in anaerobic bioreactors operated under methanogenesis inhibition conditions. The leachates from Bingerville, Abobo-Dokui, and Yopougon exhibited acidic and high organic content, particularly volatile fatty acids (VFAs), key precursors for MCFA synthesis. High concentrations of microbial communities associated with chain elongation were observed, including Clostridium (sulphite-reducing), Lactobacillus, Bacillus, and Pseudomonas (greater than 5 log10 CFU/mL). MCFA production ranged from 5 to 10 g/L, mainly C6, C7, and C8, with compositional variation depending on the SWTS. Notably, leachates from higher-income areas demonstrated higher MCFA productivity compared to those from lower-income areas. These findings highlight the potential of fresh SWTS leachates in the Abidjan district for sustainable MCFA production, paving the way for industrial applications.