Hydrolysis of sucrose by dealuminated Y-zeolites

Hydrolysis of surcose by protonated Y-zeolites was shown to be strongly accelerate by delumination. Two or less protons per unit cell provide a maximal rate constant per acid site. The rate constant is the same compared to diluted homogenous acid solution. Hydrophobic interactions essentially contribute to the adsorption of the sucrose molecule but not to the energy of the activated transition state. It was proved that the zeolite pores are able to include a sucrose molecule in addition to at least one water molecule. Because of the limited space inside the zeolite pore, a change of conformation compared with the state in solution is reqired.