Valorization of Restaurant Waste Oil Over Cow-bone Doped Siliceous Termite Hills Catalysts Towards Biodiesel Production

Treated termite hill is a potent heterogeneous catalyst in the synthesis of biodiesel from restaurant waste oil (RWO). Two catalysts (raw cow-bone supported on silica; R-SC1.5 and calcined cow bone supported on silica; K-SC1.5) were developed and used in biodiesel production. The maximum conversion of RWO was 95.12 % using K-SC1.5 at reaction time 2.5 h, methanol to oil ratio 9:1, temperature 65°C and catalyst loading of 2 %w/w. The prepared catalysts were characterized using SEM, EDAX, FTIR, XRD and BET analysis. The kinetics of the RWO with R-SC1.5 and K-SC1.5 was further studied. The Ea and A were found to be 41.4 kJ mol− 1, 53.41 kJ mol− 1 and 2.24 ×104 min− 1, 2.29×106 min− 1 respectively. The transesterification reaction adhered to first order law, while physicochemical properties were within ASTM limits. Reusability of K-SC1.5 was also examined, which revealed effectiveness up to 5 reuses without significant reduction in biodiesel yield.

Seasonal changes in populations of phlebotomine sandflies (Dipt., Psychodidae) in Kenya

An account is given of seasonal changes in the incidence and relative abundance of a number of Phlebotomine sandflies which rest in termite hills in two widely separated areas of Kenya.The annual pattern of rainfall distribution is shown to be of greater importance than the total precipitation in influencing the gross distribution and local abundance of many sandflies.Kenya sandflies fall readily into ‘ perennial ’ and ‘ rainy-season ’ groups: the former have a wide distribution and appear to breed throughout the year. The distribution of the ‘ rainy-season ’ sandflies is relatively restricted, since these species are found almost exclusively in areas with a bimodal pattern of annual rainfall; it is suggested that they may survive the intervening dry periods in larval diapause. The length rather than the severity of the dry seasons is thought to be the limiting factor in the distribution of ‘ rainy-season ’ species.Examples are given of the seasonal changes in structure of populations made up of several species sharing, in the adult form, the same termite-hill habitat.