Chemical Technology February 2015

Petrochemicals WASTE MANAGEMENT

Figure 1: Impact assessment results using the Eco-indicator 99 (E) V2.08 method/ characterisation- comparing methanol to ethanol using KOH as a catalyst

Figure 2: Impact assessment results - comparison between the catalysts, KOH and NaOH, using methanol, Eco-indicator 99 (E) V2.08/ Europe EI 99 E/E method/ characterisation

will evaporate and the remaining is washed out with other impurities during the washing process. The Life Cycle Assess- ment (LCA) was performed on a mass ratio allocation basis because of the useful by-product glycerol that is obtained during the experiments. ECO-Indicator 99 gave back the contribution of the dif- ferent biodiesel production routes in 11 impact categories namely eutrophication/acidification, climate change, carcino- gens, respiratory organics, respiratory inorganics, ecotoxicity, radiation, land use, minerals, fossil fuels and depletion of the ozone layer. The transportation distance of 5 kmwas chosen on the basis that the production facility will be placed nearby selling points in order to reduce the environmental impact of the transportation of biodiesel.

400 ml of waste cooking oil was used, however, the volume of alcohol used varied from experiment to experiment. The chosen system boundary included the production process (experiment), assembly, transportation to the selling point and burning of biodiesel in an engine, however, the initial process of growing and harvesting the oil crop was excluded because the use of waste cooking oil for the production of biodiesel is considered a waste treatment process. The system boundary remained when performing Life Cycle As- sessments for different biodiesel production routes in order to obtain a good comparison. The conducted lab scale experiments were not continuous (batch process) and the alcohol was not recovered from the process; it was assumed that 94% of the unreacted alcohol

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Chemical Technology • February 2015