摘要 |
<p>A method is described for extraction of silica and magnesium compounds, by chemical and thermal treatment of the mineral olivine. The method comprises sulphating of olivine, where olivine is mixed with concentrated sulphuric acid at a weight ratio olivine/sulphuric acid of approx. 0.5-0.67, and by heating the mixture to approx. 250 DEG C and giving the mixture a reaction time of approx. 8 hours, and thereafter dissolve the mixture in water, whereby silica percipitates to a solid and where the silica after filtration is purified in a weak solution of soda, and eventually with a weak aqueous solution of an acid or a mixture of acids. This method provides manufacturing of a purified silica solid, leaving a filtrate consisting mainly of dissolved magnesium which after further processing is transformed to magnesium compounds.</p> |