Preparation of Calcium Cyanate by the Solvent Method

کد مقاله : 1021-ICOC

نویسندگان

غزل آشوری *، محمد علی ذرعی، فاطمه ابریشمی 1381157758

چکیده مقاله

Despite the long-standing industrial importance of calcium cyanamide (CaCN₂), the scientific literature has been conspicuously silent on the preparation and intentional isolation of its immediate precursor, calcium cyanate (Ca (OCN)₂), mainly due to the extremely high aqueous solubility of this compound [1]. Here, we report the first successful synthesis of anhydrous calcium cyanate via a precision-optimized condensation-dehydration protocol using urea and calcium carbonate as inexpensive starting materials in a DMF-toluene mixture under an inert atmosphere. After refluxing at 140 °C for 15 h and drying at 120 °C, calcium cyanate was obtained in 99% isolation yield with an optimized urea: calcium carbonate molar ratio of 1:5. Controlled thermal decomposition of the resulting calcium cyanate at 800 °C for 1 h under programmed atmospheric conditions provided calcium cyanamide in 67% overall yield [2]. The structural identity and phase purity of both the intermediate and the final product were clearly confirmed by FT-IR, DSC, and powder XRD analyses, showing complete agreement with reference patterns. This method is notable for its operational simplicity, avoidance of expensive or hazardous reagents, and significant reduction in energy consumption compared to classical carbide-based routes [3]. This work not only fills a century-old gap in cyanate chemistry but also provides a scalable and cost-effective platform for the production of next-generation calcium cyanamide suitable for the agrochemical and pharmaceutical supply chains.

کلیدواژه ها

Calcium cyanamide, calcium cyanate, urea, calcium carbonate

وضعیت: پذیرفته شده