| Abstract: |
Carbonated soybean oil (CSBO) is a precursor of nonisocyanate polyurethanes (NIPUs). So far, the ruling catalysts for CSBO synthesis through the coupling of epoxidized soybean oil (ESBO) with CO2 are homogeneous ones. In this work, a heterogeneous catalyst, 5 wt % H3PW12O40 (PW)/ZrO2 was investigated for the coupling reaction and proved quite efficient. However, the catalyst showed poor reusability due to the difficult elimination of bulky by–products retained in the spent catalyst. To remedy bulky by–products retained in the spent catalyst. To remedy this deficiency, the 5 wt % PW/ZrO2 was modified with 0.3% Pt. It is found that Pt addition markedly improved the reusability of the 5 wt % PW/ZrO2 without loss in carbonation activity. An ESBO conversion of 78.3% was obtained at the end of third recycle, indicating that Pt species incorporated could promote the removal of the byproducts and hence protect the active centres of 5 wt %PW/ZrO2 catalyst.
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