Kamrun Nahar and Sanwar A. Sunny Pages 18 - 31 ( 14 )
Vertical expansion of Jatropha curcas L by roof-top gardening with pot experimental studies were carried out to produce feedstock of Jatropha for production of biofuel and related byproducts. The plant can grow on eroded land and needs comparatively limited amounts of natural resource and capital inputs and garners much interest from developing nations based on an agrarian societal ecosystem. The experiment also focused in evaluating the physiochemical parameters of resulting Jatropha oil, biodiesel, glycerin and seed cake characteristics after extraction. The seeds of the plants after two years of germination were collected from the earthen pot to extract fuel. After maturity, the plant provided about 250 ml of crude oil per plant and the characteristics of fuel responded better (Flash point of 254°C, Ignition point 323.6°C, Specific gravity of 0.922, Densi- ty 0.919, high Cetane number, or Ignition Quality, of 56.7, Sulfur % of 0.125, Iodine (103.67 mg/g) and Saponifi- cation value of 196.85 mg/g) in comparison to fossil fuel. Higher nutrient content were found in seed cake residue obtained after oil extraction, which could potentially be used as an excellent organic fertilizer, with nutrients value, N = 3.48%, P2O5 = 1.78% and K2O = 1.57%. Also the oil contains a comparatively high percentage of unsaturated fatty acid (79.34%) resulting in characteristically low levels of free fatty acids, which improves storability. The crude oil without any modification could easily be used in lamp for illumination. The high iodine value and the presence of unsaturated fatty acids enables it to remain fluid at lower temperatures. The low sulfur content equates to less harmful sulfur dioxide (SO2) emitted when the fuel is burnt. The crude oil then converted to biodiesel by transesterification process with the byproduct glycerin. 250 ml crude oil could produce about 243 ml of biodiesel. Biodiesel could be used in farming machineries, irrigation pumps, building generator and transporta- tions with greater environmental benefits than conventional carbon-based fossil fuels. Roof-top gardening of plants in this setting also allows for a cooling effect in direct response to urban heat-island effects.
Biodiesel, glycerin, jatropha curcas, nutrient uptake, physiochemical properties, seed cake.
Department of Environmental Science and Management, North South University, Dhaka, Bangladesh.