Optical activity and faraday effect in some mineral and vegetable oils.

Abstract

This Thesis presents results of a study of Optical Activity and Faraday Effect (OAFE) in some mineral and vegetable oils in the temperature range of 6°C to 45°C and magnetic field up to 140mT. Intrinsic birefringences responsible for Optical Activity were found in vegetable oils with impurities and all mineral oils. The results of Optical Activity in both types of oils obeyed the equation (0. 1) where Qw .,, is the angle at which minimum irradiance I min occurs in water and other substances which are optically inactive, </> is the rotation angle in the medium and A is a rotation due to impurity concentration. The results show that, the more the impurity concentration is in the vegetable oil, the greater the rotation angle. The rotation angle is almost directly proportional to impurity concentration. When static magnetic field was applied to mineral oils and vegetable oil with impurities, the rotation angle obeyed the equation </> = Ml<L + VHL (0.2) where M is the intensity of magnetisation of the medium, K the Kundt's constant (rad/m), L path length in metres, V the Verdet's constant in radT-1m- 1 and H is the magnetic field intensity in Am-1 Heavy diesel oils like red diesel, Esso diesel and Fina diesel No.1 rotate more the vibration plane and therefore possess more intrinsic birefringences than light diesel such as Nors Hydro AS diesel and petrol. In vegetable oi ls free from impurities