Preparation of Calcium Magnesium Mixed Hydroxide Nanoparticles from Zeolitic Tuff

摘要

The present invention relates to a method for preparation of calcium magnesium mixed hydroxide nanoparticles from zeolitic tuff. In the method of this invention, zeoltic tuff was rolled crushed and ground in small grains and then sieved to obtain 44 µm sized fractions. The pulverized zeolitic tuff is mixed with concentrated hydrochloric acid and agitated from time to time and left 24 hours at ambient temperature. An aqueous acid colored solution formed is separated by decantation and filtration. The aqueous acid colored solution is treated sodium hydroxide solution and adjusting the pH at 5.0 to obtain red-brown particles. Red-brown particles removed from the mixture by filtration, and the filtrate is treated with sodium hydroxide to form white milky particles by adjusting the pH at 13 - 14. Milky white particles treated by water-ethanol mixture with agitation for 60 min and then filtered and dried to give ultrafine white powder.