(339e) In-Situ Transesterification of Chinese Tallow Oil to Biodiesel

Biodiesel is a renewable fuel produced from vegetable oils and animal fats that conforms to the ASTM D6751 standard. In 2006, biodiesel production was approximately 80 million gallons. If the industry continues to grow at the present rate, this biofuel could contribute to a significant reduction of the US dependency on foreign oil. To maintain this rate of growth, other oil feedstocks will have to become available. Several new and innovative feedstocks have captured the interest of biodiesel producers, one of those being Chinese tallow. The Chinese tallow tree (sapium sebiferum) seeds produced contain approximately 40% - 45% extractable material. The oil yield per acre is 10 times higher than soy bean oil.

Conventionally, Chinese tallow oil would be extracted from the seed prior to transesterification using hexane or a press. However, transesterification of the oil through traditional methods has proven to be difficult. Mostly composed of saturated fatty acids, Chinese tallow oil solidifies when exposed to ambient temperatures. Excess heating is required to maintain the oil's liquid phase so that transesterification can be successfully performed. In-situ transesterification of Chinese tallow seeds simultaneously combines the steps of lipid (oil) extraction and transesterification to produce biodiesel. Integration of these stages could reduce the need for excess heating while maintaining a high conversion to biodiesel. The paper will describe results obtained on the in-situ transesterification of Chinese tallow seeds, biodiesel ASTM testing, and processing economics.