Optimization of reaction of ulexite ore with sulphur dioxide in aqueous medium in sodium pentaborate production

In this study, it has been determined optimum conditions of dissolution of ulexite, produced in huge amounts in our country, with sulphur dioxide in aqueous media and production of sodium pentaborate has been investigation from solutions obtained at the optimum conditions. Sulphur dioxide is a gas being by-product from firing of fossil fuels or roasting sulphurous ores. Emission of this gas to atmospher is dengerous for animate and inanimate beings. Thus, both a harmfull gas is caught and a valuable product is obtained. In the study, ulexite ore obtained from Eti Maden Works was ground with a laboratory grinders. Ground ores are seperated with ASTM standard sieves to -45µ, -75µ, -150µ, -250µ fractions. After preliminary experiments, tempereature, particle size, time and solid/liquid ratio were selected as parameters. Taguchi L16 and L9 orthagonal arrays used for experiment design in order to determine optimum parameter levels. After determining the optimum conditions, solution obtained under optimum conditions was evaporated and sodium pentaborate was obtained with crystallization.