In brief
Benin’s AMAVI has recycled more than 150,000 litres of used cooking oil into soap and biodiesel, partnering with over a hundred restaurants and a Chinese technology alliance. The company plans to produce over three tonnes of biodiesel per day by 2030, boosting environmental protection and rural energy independence.
Up on a humid plateau just north of Benin’s capital, Cotonou, the local enterprise AMAVI is turning a daily environmental nuisance into a clean‑energy resource. The company collects and processes the liquid remnants of fried dishes and sautéed vegetables that would otherwise find their way into streets, rivers, or landfills, and re‑purposes them as soap and biodiesel. This effort not only diverts waste from the landscape but also creates renewable products that can replace diesel in rural transport and power generation.
When kitchens finish a meal, the residual fat and oils known as used cooking oil are typically discarded with the trash. The chemical composition of this liquid—rich in phospholipids and free fatty acids—gives it a high potential for environmental harm. If it seeps into groundwater, it can alter soil chemistry, while flames from open‑air burning generate particulate matter that weakens air quality and can provoke respiratory distress. Long‑term exposure to these contaminants has been linked, according to scientific literature, to higher rates of respiratory disease and certain cancers.
Carmel Djiha, founder of AMAVI, says:
Consuming used cooking oil is harmful to human health and can cause cancer and respiratory problems in the long term.He warned that improper disposal can contaminate soil and disrupt aquatic ecosystems, underscoring the need for systematic collection and re‑use.
AMAVI’s collection network is anchored in the Oued‑Kpossidja locality, about 40 km from the city center, where the majority of the country’s hotels and restaurants cluster. By partnering with more than 100 food‑service operators, the firm receives a steady stream of leaking oil that would otherwise be discarded improperly. Weekly pick‑ups are coordinated by trained staff who transport the fluid to a central facility under temperature‑controlled conditions to preserve its quality during transit.
At the processing plant, the extracted oil first undergoes mechanical filtration that removes coarse solids and separates water through settling tanks. Once clarified, the liquid is split into two separate streams. The portion destined for soap production is reacted with a lye solution in a controlled caustic environment that yields a high‑purity soap base suitable for local markets. The second stream feeds a transesterification unit where the oil is chemically transformed into biodiesel, producing a renewable diesel analogue that can be directly pumped into engines designed for agricultural machinery and standby generators.
By supplying biodiesel to remote farms and energy‑constrained villages, AMAVI provides a cleaner alternative to animal‑fat diesel and kerosene, which are currently the mainstay of rural transport in the region. The substitution of conventional fuel with biodiesel cuts sulfur emissions, reduces particulate pollution, and lowers overall greenhouse‑gas outputs. In addition, the soaps generated from waste oil contribute to the local economy, offering a biodegradable and climate‑friendly cleaning product for households and businesses.
Policy enforcement in Benin dates back to 2003, when the government enacted regulations that forbid the release of used oil into soil, surface water, groundwater, or sewage systems, and outlawed its unauthorized combustion. The restrictions aim to curb the environmental degradation that accompanies uncontrolled disposal. By channeling the waste into lawful conversion processes, AMAVI not only complies with these statutes but also demonstrates a viable model for regulatory compliance that protects both ecosystems and public health.
Recognizing the need for advanced technology, AMAVI entered a joint venture with China’s Henan Hengyong in 2024. The partnership brings state‑of‑the‑art oil‑processing equipment to Benin, while Henan Hengyong provides ongoing technical training for AMAVI’s workforce. The transfer of knowledge includes operating the transesterification reactors safely, monitoring quality standards, and scaling up the filtration infrastructure, thereby positioning AMAVI to handle larger volumes of used oil with improved efficiency.
Since its initiation in 2023, AMAVI has treated more than 150,000 litres of used cooking oil, a volume that represents the equivalent of an average household’s annual consumption of fried foods. The founder, Djiha, revealed plans to industrialise biodiesel production by 2030, targeting a daily output exceeding three tonnes. Such an expansion would not only meet growing local demand for renewable fuel but also significantly reduce the country’s reliance on fossil importation, thereby reinforcing energy security and environmental stewardship.
AMAVI’s experience illustrates how a single resource—discarded cooking fat—can be re‑imagined as a dual‑benefit product that mitigates pollution and supplies renewable energy. The company’s demonstration of conversion technology, coupled with international collaboration and solid regulatory support, offers a replicable framework for other African nations grappling with informal waste disposal. As Benin strides toward its 2030 biodiesel goal, AMAVI’s model underscores how science‑driven waste management can accelerate sustainable development and public‑health protection.
