Abstract
Ground water was collected from a depth of 1,200 m in the Al-Qasim area in mid-Saudi Arabia. This underground water contains minerals, mainly Fe and Mn and radio-nuclides like radium and other ionic materials. This water was filtered through a sand bed, which contains layers of sands of different sizes in order to remove those impurities from water. Mn and Fe were deposited on outer layer of each sand granule during filtration and radium was adsorbed on surfaces of these minerals. Ra was separated from these minerals by dissolving them in various acids such as ascorbic acid, citric acid, tannic acid, salicylic acid, tartaric acid and lactic acid under different experimental conditions like acid concentration, contact time, shaking speed, particle size, temperature and liquid/solid ratio. The effectiveness of these acids on radium removal was found as follows: ascorbic acid a parts per thousand citric acid > tartaric acid > tannic acid > lactic acid > salicylic acid. Various reaction parameters were also optimized. Reaction kinetic and mechanism parameters of dissolution process were studied and compared with other published data.