Extension of Comparison of the Mopping Ability of Chemically Modified and Unmodified Biological Wastes on Crude Oil and Its Lower Fractions

Abstract

Aim: Is to extend our study on the number of locally available sorbents that can be used in oil/chemical spill clean-up. Study Design: Carbonized and uncarbonized sorbents were separately encased in a sac like booms of 2cm x 2cm x 1cm dimension and used to mop up spills of different hydrocarbons. Place and Duration of Study: Carbonization of sorbents was carried out at Federal Science Equipment Development Institute Enugu in Enugu State, Nigeria while the rest was done at Mechanical Engineering workshop, Nnamdi Azikiwe University Awka, Anambra State Nigeria between March –May 2011. Methodology: Activated and unactivated powders of protein wastes (feather, goat hair) and cellulosic wastes (coco-nut husk, corn-cob), separated into two particles sizes of 325µm and 625µm were used to mop up spilt crude oil, diesel, kerosene and petrol and each were allowed a contact time of 30, 60, 90 and 120 mins contact time before they were hung in air to drain unabsorbed liquids. Recovery was carried by mere pressing, differences in weight were obtained and used for calculation of % absorption, recovery and retention. Results: It was observed that all the sorbents mopped up appreciable quantities of all the sorbates within an average of 90mins contact time. Large volumes of the hydrocarbon liquids were recovered and retained, sorbates were mopped as- crude oil > diesel > kerosene > petrol, proteinous sorbents with oleophilic and aquaphobic properties absorbed more of all the hydrocarbon liquids than cellulosic sorbent at any particle size and contact time, although both showed high sorption capacity for the sorbates. Particle size of sorbents, activation, contact time, molecular chain length and viscosity of sorbates determined the amount of hydrocarbon absorbed/adsorbed, recovered or retained. The amount of residual leachable diesel in the sorbent was below 3%. Conclusion: Sorbents studied showed high sorption capacity for the sorbates.