Physical and mechanical properties of rice straw treated with solution of potassium hydroxidefrom wood ash

Abstract

The use of agricultural waste as alternate building material has had great deal of interest in recent years. Therefore, these wastes have often bad physical properties that need to be improved. This experimental research investigation aims to explain the influence of potassium hydroxide on the rice straw properties. The potassium hydroxide was obtained by crystallizing wood ash solution. Five solutions containing different ratio of potassium hydroxide were made and used to treat rice straw. Water absorption, direct tensile test and density were performed on straw to determine the influence of treatments on their physical and mechanical properties. Modifications in rice straw structure were investigated by dissecting microscope and scanning electron microscopy (SEM). All applied solutions resulted in a reduction of the water absorption capacity and increament in tensile strength. For improved physical and mechanical properties of vegetal straw, treatment with solution pH 9.92 (containing 8 kg/l) of potassium hydroxide was recommended.