Leaching of phase-separated glasses in the Na2O-B2O3-SiO2-Fe2O3 system
Keywords:system Na2O-B2O3-SiO2-Fe2O3, phase-separated glasses, chemical durability, magnetite
The leaching behavior of heat-treated phase-separated iron-containing sodium borosilicate glasses within the range of compositions of 8Na2O·(22 – х)B2O3·70SiO2·хFe2O3, where х varies from 0.3 to 10 mol.%, and (8 – x)Na2O∙22B2O3∙70SiO2· xFe2O3, where х varies from 2 to 6 mol.%, in the 3M aqueous HCl solution at boiling, was studied. It has been shown that the introduction of Fe2O3 in these phase-separated glasses increases their chemical durability, the values of porosity and the average pore diameter, but reduces the specific surface area in the porous glasses based on them, compared with glass without Fe2O3. The compositions suitable for producing porous glasses were determined.