Thermal and hydrolytic stability of grafted ester groups of carboxylic acids on the silica surface

Aliphatic carboxylic acids in the form of triglycerides are promising renewable raw materials for the development of green nanotechnology of biomass catalytic pyrolysis with the use of silica-supported catalysts. Therefore, the research of hydrolytic stability and thermal transformations of carboxylic acids on the silica surface is of practical importance. Since such investigations for carboxylic acid grafted ester groups have not been carried out, the hydrolytic stability of chemisorbed carboxylic acid fragment = Si-O-CO-R was studied using the high-vacuum TPD-MS system. It was found that only ~46 % of grafted ester groups of carboxylic acids are hydrolyzed in saturated water vapors at room temperature during an hour.