KULTIVASI Botryococcus Braunii MEMANFAATKAN AIR DADIH (WHEY) TAHU SEBAGAI POTENSI BIODIESEL

Abstract

Production of biodiesel comes from trans-esterification reaction of fatty acid which produces methyl ester. Vegetables, animals and microalgae can be used for fatty acid sources by their oil, but microalgae have a more beneficial prospect compared to vegetables and animals. Microalgae have fast grow-rate, high oil productivity, low production cost and not having a competition with food industries. Among microalgae, Botryococcus braunii is the one with high oil quantity inside their cells (25 – 75 %). The wastewater of tofu industries is liquid residual from soybean processing becomes tofu which having a nuisance for the environment. This wastewater, usually called whey, is still containing organic materials such as water (99,34 %), protein (1,73 %), fat (0,63 %), nitrogen content (0,05%) and ash (0,11 %) and COD. Organic materials have effect to stimulate microalgae’s growing. Objectives of this experiment are the influence of tofu whey addition at different concentrations toward biomass and lipid produced. This experiment provided the result which optimal cultivation of Botryococcus braunii reaches when using 10% concentration tofu whey with optimal optical density (OD) at day 9 (0,802), 2,4101 gram/litre of gained biomass and 0,8716 gram/litre of lipid production.,better than cultivation of Botryoccus braunii using syntetic nutrient. Maximum COD reduction was gained at 15% tofu whey addition with 88,51% efficiency. COD reduction at optimal tofu whey addition (10%) is 83,33%.