Preparation of CaCO3 using mega-crystalline calcite in electrical furnace and batch type microwave kiln

• Published in: Journal of industrial and engineering chemistry (Seoul, Korea) Vol. 19; no. 5; pp. 1507 - 1516
• Main Authors: Hwang, Dae Ju, Ryu, Jae Yong, Park, Jung Ho, Yu, Young Hwan, Choi, Moon Kwan, Cho, Kye Hong, Ahn, Ji Whan, Han, Choon, Lee, Jong Dae
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25-09-2013; 한국공업화학회
• Subjects: Batch type furnaces; Breaking; Calcination; Calcinations; Calcite; Calcium carbonate; Carbonation; Furnaces; Hydration; Kilns; Mega-crystalline calcite; Microwave; Microwave kiln; Microwaves; 화학공학; Microwave; Carbonation; Calcinations; Hydration; Mega-crystalline calcite; Microwave kiln
• ISSN: 1226-086X; 1876-794X
• DOI: 10.1016/j.jiec.2013.01.017

Mega-crystalline calcite (m-CC) breaks apart easily during calcination, and cannot be easily converted to CaO due to its characteristic that requires massive heat consumption. To solve this problem, the calcination characteristics were compared using electrical furnace (EF) and batch type microwave kiln (BM). After hydrating the manufactured CaO, Ca(OH)2 was produced, and through the carbonation process, CaCO3 was synthesized.
The results of the XRD pattern of CaO that was formed through calcinations indicated that decarbonation reaction occurred as 98.2wt.% by EF for 240min, and 97.8wt.% by BM for 30min at the same temperature of 950°C. Hydration results revealed that CaO by EF was high-reactive whereas CaO by BM was medium-reactive. CaCO3 was synthesized through the carbonation process. At 25°C, in both cases, colloidal-shaped CaCO3 was found, and the more spindle-shaped CaCO3 by cubic-shaped self assembly was synthesized at higher temperatures. However, in case of EF, Ca(OH)2 existed in products.