The hydrophobisation of activated carbon surfaces by organic functional groups

A technique of hydrophobic surface design with a high degree of structural homogeneity has been developed for catalytic materials. Mesoporous activate d carbons and silica gel were modified by (A) treatment with vinyltrimethox ysilane (vtms) or (B) chlorination with carbon tetrachloride followed by re action with a Grignard reagent. Evidence for silica gel modification was ob tained from FT-IR and C-13 NMR spectroscopy and from elemental analysis. Ca rbons chemically modified with alkanes and olefins were studied using therm ogravimetry (TG) and the results compared with those for the modified silic a gel. TG and differential scanning calorimetry (DSC) revealed that the pol ymerisation of vinyl groups occurred on the carbon surface. The participati on of the carrier surface in the initiation of radical processes has been d iscussed.