Surface Phosphorylated Activated Carbons: Preparation and Acidity Studies

Here we report on the phosphorylation of activated carbon (AC) at 500–800 °C. From thermal, titrimetric, and catalytic data, high surface acidity of the prepared solids is attributed to the total concentration of the protogenic groups. Transmission electron microscopy and nitrogen physisorption measurements showed a chemisorption-induced contraction of microporosity. The most active catalysts prepared at 700 °C contain 1.04 mmol g−1 of the phosphonic groups and supports dehydration of isopropanol with about 100% conversion and 100% selectivity to propylene at 170–180 °C.