(600af) Chicken Manure As Heterogeneous CaO Catalysts for Biodiesel Production from Transesterification of Waste Cooking Oil

Due to diminishing of fossil fuel and environmental problems, biodiesel has become one of the environmentally benign and renewable energy fuels due to its raw material being in abundance, its potential for large scale production, and its better physical and chemical properties as compared to the petroleum-based diesel e.g. better lubricating efficiency, lower sulphur contamination, and very few pollutants produced. Calcium oxide (CaO) has been intensively used as a heterogeneous base catalyst for biodiesel production via transesterification due to its high basicity and strong basic strength, and non-toxicity. Recently, the discovery of inexpensive catalysts with high catalytic activity from the abandoned waste materials (e.g. eggshell, animal bone, crab and oyster shells, fly ash and etc.) makes the biodiesel production process highly capable of competing on a cost and quality basis with the diesel fuel produced from petroleum.

In this work, new application of chicken manure, which is usually as a fertilizer, has been explored. Interestingly, chicken manure contains large amount of calcium compounds (over 60 wt. %) which can be used as a new source of CaO catalyst. Calcination process was used to convert the calcium compounds in chicken manure into the active CaO catalyst. Hammett indicator test showed that the basic strength of the CaO catalysts obtained after calcination of chicken manure lie in the range of 15 < H_< 18.4, indicating that the surface basicity of these catalysts could be attributed to the strong basicity of the metal–O groups (Lewis base) which is considered as a strong base for transesterification reaction. Waste cooking oil was then used as a feedstock for biodiesel production by using the CaO catalyst derived from chicken manure. Transesterification was carried out and the oil conversion and FAME (or biodiesel) yield were optimized by varying the molar ratio of alcohol to oil , catalyst concentration, temperature, and time. The chicken manure-derived CaO catalyst exhibits high catalytic performance for the transesterification of waste cooking oil with over 85% of FAME (or biodiesel) yield. The utilization of chicken manure as a source of catalyst not only addresses environmental problem of waste, but also economic aspects of biodiesel production by using waste as catalyst and feedstock.