Physical, Mechanical Properties and Oil Content of Selected Indigenous Seeds Available for Biodiesel Production in Bangladesh
This study identifies the physical and mechanical properties and oil contents of seeds of four indigenous plants in Bangladesh, namely the Jatropha, Karanj, Castor, and Rubber. Physical properties such as length, width, thickness, slender ratio, weight and bulk density were measured to find out the size, shape and space required by the seeds. Mechanical properties like hardness and crushing strength of the seeds were determined as well. All these properties are necessary for processing and storage of the seeds for oil extraction. Hardness and crushing strength of the seeds were measured by a Manual Hardness Tester. Oil content was measured by chemical method (Cold percolation method). Among the four types of seeds, Rubber seed was the largest with a length of 21.15 mm followed by Karanj 17.88 mm, Jatropha 17.05 mm and Castor 11.76 mm. The slender ratio of Jatropha, Karanj, Castor and Rubber seeds were found to be 1.78, 1.24, 1.87 and 1.13 respectively. Jatropha and Castor seeds had similar cylindrical shape with rounded tips. Karanj seed was found to be circular and flat. Shape of the Rubber seed was rectangular, inflated but slightly flattened in thickness. Rubber seed was the heaviest (4.31 g), as its size was also biggest followed by Karanj (1.19 g), Jatropha (0.76 g) and Castor (0.19 g), respectively. Hardness were found to be 2.69, 1.87, 1.70 and 8.56 kg for Jatropha, Castor, Karanj and Rubber seeds while crushing strength were 38.08, 26.56, 24.06 and 121.16 kg/cm2, respectively. The oil contents of Jatropha, Karanj, Castor and Rubber seeds were 32.36%, 31.75%, 67.67%, 38.96% by weight respectively. All the four types of seeds contain satisfactory amount of oil which can be extracted commercially and checked for their suitability for the production of biodiesel.