BIOREMEDIATION OF PETROLEUM HYDROCARBONS IN REFINED OIL GASOLINE-POLLUTED SOIL USING SWEET POTATO PEELS

ABSTRACT Bioremediation of refined oil (gasoline)-polluted soil using sweet potate peels was Investigated. Top soil (0 to 20 cm depth) was randomly collected from four points using a Durch suger, then bulked to farm composite soil sample. Four kilograms (4kg) of each composite soil was weighed and transferred into twelve (12) labeled plastic buckets with drainage holes at the base arranged in triplicate. The soils contained in the buckets were polluted with 500 ml of refined oil (gasoline) each except the natural soil (control 1) and were mixed thoroughly and allowed for 14 days to allow for acclimatization between the soil and gasoline. The gasoline polluted soil was then amended with 400g, 600g and 800g each of ground potato peels except for control 2 which contained only gasoline polluted soil The set-up was allowed to stand for 80 days after which the soil samples were collected and analyzed for physicochemical properties. total petroleum hydrocarbon and total microbial counts. The result of the total petroleum hydrocarbon (TPH) analysis showed that the higher the concentration of the agro-wastes (sweet potato peel), the more the reduction of the hydrocarbon content (400g:751.07±4.01.600g: 640.60± 18.40,800g: 564.00±66.72). The results also indicated a sequential increase in physicochemical parameters with increasing quantities of potato peels (800g: > 600g > 400g) (Table 3). It therefore suggests that the treatment of sweet potato peels should be considered as one of the best options for bioremediation of refined oil (gasoline) polluted NOLT