가압수열 수용액중에서 인산석고로부터 $\alpha$형 반수석고의 생성에 미치는 염류의 영향

Effects of Salts on the Formation of $\alpha$-Calcium Sulfate Hemihydrated from by-Product Gypsum of Phosphoric Acid Process at Hydrothermal Condition

  • 이구종 (한양대학교 무기재료공학과) ;
  • 최상흘 (공업시험원 요업과)
  • 발행 : 1987.04.01

초록

The effects of salts such as aluminum sulfate as inorganic salt(2-4%), and sodium salts of citrate, tartrate, succinate, potassium tartrate and gelatin as organic salts(0.1%) on the formation of ${\alpha}$-calcium sulfate hemihydrate from by-product gypsum of phosphoric acid process under hydrothermal condition at 123$^{\circ}C$ and 133$^{\circ}C$ were investigated. Aluminum sulfate solution exhibited the catalystic effected on the crystallization of ${\alpha}$-calcium sulfate hemihydrate of which was assumed in the prismatic form, and organic salts solution exhibited little effect on the catalystic action to the crystallization, than inorganic salts. In the acidic solution with sulfuric acid(pH=2), needle like crystal of calcium sulfate hemihydrate was obtained. Hydrothermal process with aluminum sulfate solution also showed certain amounts of impurity removal such as phosphorus penataoxide from calcium sulfate hemihydrate.

키워드

참고문헌

  1. Gypsum and Lime no.149 Manufacture of High Strength Hardened Gypsum from Powdery Gypsum S.Sukimoto;O. Matsuda
  2. Gypsum and Lime no.51 The Catalitic Effect of Salts and its Mechanism in Crystallization of α-Calcium Sulfate Hemihydrate M.Sekiya
  3. Gypsum and Lime no.199 Effects of Salts on the Formation of α-Calcium Sulfate Hemihydrates in Aqueous Salts Solution under the Atmospheric Pressure S.Sukimoto;N.Hara;H.Mukaiyama
  4. Gypsum and Lime no.200 Formation of α-Calcium Sulfate Hemihydrates in Aqueous Salt Solutions under the Atmospheric Pressure and Their Physical Properties ibid
  5. Gypsum and Lime no.193 Production of α-Hemihydrate under the Pressure of Water Vapor at Atmospheric Pressure S.Sukimoto;H.Mukaiyama
  6. Reports of the Industrial Research Institute no.35 Formation of α-Calcium Hemihydrate under the Pressure of Water Vapor at Atmospheric Pressure and their Physical Properties S.Sukimoto;H.Mukaiyama