Calcium Hydroxyapatite: A Highly Stable and Selective Solid Catalyst for Glycerol Polymerization
نویسندگان
چکیده
Calcium-based catalysts are of high interest for glycerol polymerization due to their catalytic activity and large availability. However, poor stability under reaction conditions is an issue. In the present study, we investigated Ca-hydroxyapatites (HAps) as one most abundant Ca-source in nature. A stochiometric, Ca-deficient Ca-rich HAps were synthesized tested reaction. Deficient stochiometric exhibited a remarkable 100% selectivity triglycerol at 15% conversion 245 °C after 8 h presence 0.5 mol.% catalyst. Moreover, same conditions, HAp showed (88%) di- 27%. Most importantly, these unexpectedly stable towards leaching based on ICP-OES results. tests characterization analysis performed by XRD, XPS, IR, TGA-DSC ICP-OES, found that can be deactivated products themselves, i.e., water polymers.
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ژورنال
عنوان ژورنال: Catalysts
سال: 2021
ISSN: ['2073-4344']
DOI: https://doi.org/10.3390/catal11101247