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This paper assessed the technical and economic viability of biodiesel production from Second-generation feedstocks native to East Africa, which included Castor, Croton, and Jatropha. Their oils were converted to biodiesel by transesterification and characterizations of B100 and B10 done following ASTM D6751. ASPEN Plus V11 was used in process simulation and profitability analysis. Oil yields obtained ranged from 29.5% to 35.6%. B100 and B10 properties conformed to ASTM D6751. The negative Net Present Values obtained render B100 and B10 production uneconomical unless incentivized. Sensitivity analyses showed that NPV varied with feedstock cost and biodiesel selling prices. This assessment established that though a B10 policy based on second-generation feedstocks is technically viable, interventions are needed to make it profitable in Uganda.

Global energy demand continues to increase owing to advancements in key growth sectors of Economies. Transportation-related emissions resulting from petroleum use account for 23% of total energy-related CO2 emissions. Biofuels including biodiesel are renewable substitutes for transportation fuels that have attracted global interest. This paper reviewed existing literature on technological, economic, and life cycle environmental aspects vital for assessment of the viability of production of second-generation biodiesel including the B10 blend advocated for Uganda. The quantity of biodiesel required to fulfil a B10 blend for Uganda’s downstream petroleum sector is one hundred million litres per annum. To meet this demand, 50,000 ha of land is required for cultivation of biodiesel feedstocks against the available 6,900,000 ha. Jatropha, castor, and croton, offer agronomical advantages. Biodiesel produced from these feedstocks through transesterification, should conform to ASTM D6751/EN14214 standards. Physicochemical, economic, and environmental assessments are vital to confirm its techno-economic viability.

Effects of alkaline surface modification and carbonization on biochemical properties of selected rice and coffee husk varieties in Uganda were studied. Alkali pre-treatment was done by washing the husks in NaOH at a 15:1 liquor ratio. Pre-treatment is used in biomass conversion to overcome chemical and structural difficulties. Carbonization resulted in production of bio-char. Results showed increased cellulose contents for both the husks and their bio-chars after pre-treatment with NaOH solution. Lignin and hemi-cellulose compositions were reduced after pre-treatment in NaOH solution. Bio-chars for all rice husk varieties showed an increase in lignin content after carbonization. Lignin contents for Robusta coffee husks also increased after carbonization. Cellulose content in bio-chars of both rice and coffee husks reduced drastically after carbonization. A simple regression model relating bulk density and biochemical composition was developed at an accuracy of 70%. Alkaline surface modification and carbonization effects on biochemical properties are due to their impact on the non-cellulosic material and hydrophobicity, respectively, on the fibers.