MANUFACTURE OF GYPSUM BOARD FROM EGGSHELL …
Natural gypsum mining in Indonesia alone, according to statistics from year to year the number increased as shown in Table-1 [1]. ... 150 ml). Previous sulfuric acid used diluted from concentrations of 97% to a concentration of 15%, ie by mixing sulfuric acid 97% by volume of 23.19 ml with distilled water volume of 126.80