Determination of Nitrogen and Sulphur Oxides Produced During Combustion of the Jatropha Cake as a Measure of the Level of Pollution When the Cake is Used as a Fuel
S. Mbera *
Department of Chemistry, University of Zimbabwe, P.O. Box MP167, Mt Pleasant, Harare, Zimbabwe
L. R. M. Nhamo
Department of Chemistry, University of Zimbabwe, P.O. Box MP167, Mt Pleasant, Harare, Zimbabwe
T. Nyakungu
Department of Chemistry, University of Zimbabwe, P.O. Box MP167, Mt Pleasant, Harare, Zimbabwe
*Author to whom correspondence should be addressed.
Abstract
Jatropha cake is a promising renewable energy source after proving difficult to be used as feedstock. Its possible use as a combustible fuel makes the Jatropha cake pellet important as a source of potentially harmful gases to the users and the environment. This makes it imperative to determine the level of pollution caused by the Jatropha cake bio-pellet so as to take the necessary precautions to prevent the hazards that may be associated with its use as fuel if necessary. Jatropha cake samples were burned in a furnace to determine the amount of nitrogen oxides (NOx) and sulphur dioxide (SO2) produced during complete combustion. The effect of temperature on the production of these gases was investigated by altering the furnace temperature from 300°C to 1200°C. NOx and SO2 were collected in a mixture of aqueous ammonia and hydrogen peroxide and quantified as nitrates and sulphates respectively. The results showed that the production of NOx and SO2 generally increased with increasing temperature with the highest amount of NOx at 1200°C and that of SO2 at 800°C. The amounts of NOx and SO2 were 0.02mg/kg and 0.15mg/kg respectively. It was observed that the Jatropha cake pellet is a more environmentally friendly source of energy than the fossil fuels.
Keywords: Jatropha cake, nitrogen oxides, sulphur dioxide, renewable energy, pollution