Novel attempts for the synthesis of calcium sulfate hydrates in calcium chloride solutions under atmospheric conditions

作者：Yang Jen Chang; Wu Hong Da; Teng Nai Chia; Ji Dian Yu; Lee Sheng Yang^*

来源：Ceramics International, 2012, 38(1): 381-387.

DOI：10.1016/j.ceramint.2011.07.017

• Calcium sulfate
• Calcium chloride
• Dehydration
• Processing window

The medical grade calcium sulfate is widely used in clinical applications for treating bone defects. A high-purity and predictable calcium sulfate (CS) synthesis process is desirable in the medical industry. The objective of this study was to develop a one-pot method for the direct preparation of calcium sulfate hemihydrates (CSHs; such as the alpha- and beta-forms) in a CaCl(2) solution. CS was synthesized by mixing K(2)SO(4) and Ca(NO(3))(2)center dot 4H(2)O under various CaCl(2(qa)) concentrations and reaction temperatures under atmospheric pressure. The calcium sulfate dihydrate (CSD) was found to be an intermediate phase that converts to CSH during the synthesis process, and alpha-CSH was gradually transformed from beta-CSH over time. Moreover, the kinetic of CSD conversion to CSH was strongly accelerated by increasing the CaCl(2) concentration. As the reaction temperature was fixed in 90 degrees C, the form of the CS reactant with an increase in the CaCl(2) concentration was in the following sequence: CSD -%26gt; CSD + beta-CSH -%26gt; CSD + beta-CSH + alpha-CSH -%26gt; alpha-CSH. In this study, the synthesis processing window of the CS reactant was established according the test results, and it

• 出版日期2012-1