Energy Reports (Nov 2022)
Valuation of cashew nut shell for the production of biofuel
Abstract
The valuation of CNSL (cashew nut shell liquid), a by-product of the cashew nut sector, could be a solution to improve access to energy in sub-Saharan Africa. This work aimed by studying the valuation of CNSL for its use in a generator mixing with diesel. With this in mind, the CNSL was initially purified by filtration at 25μmafter solubilization in an organic solvent, subsequently eliminated by evaporation. CNSL purified with ethanol presented the most interesting physicochemical characteristics. Blends containing 10% to 60% (vol.) of purified CNSL in diesel fuel were then produced and characterized in terms of lower calorific value, water content, acidity, density, and viscosity. Diesel engine combustion tests of these blends were carried out and the influence of the purified CNSL content on the combustion behaviour of the blend was studied. Observations of the piston head and the valve after 10 h of operation reveal the onset of fouling but which remains comparable to that observed for pure diesel. These first very promising results show that the use of CNSL as a fuel up to 60% in a stationary diesel engine is possible and efforts are still needed to improve the purification technique.