Abstract: The present invention provides a photocurable composition prepared using mercapto benzophenone compounds as key raw materials. The present invention aims to solve the problems existing in the prior photo-curing technology that low-molecular photoinitiators are easy to remain and migrate, while macromolecular photoinitiators has low initiation efficiency due to a low content of effective components and also has the problem of certain migration. The photocurable composition in the present invention can be easily prepared and has high addition efficiency with ethylenically unsaturated compounds, and the photocurable composition obtained by addition has no residual mercapto and has features of high initiation activity and zero migration rates when it is used in photocurable coatings, binder and ink formula.

Abstract: A catalyst for hydrodemetalization of heavy oil, especially residuum oil, and a process for preparing the same, wherein said catalyst comprises the metal elements of Groups VIII and/or VIB as active components supported on an alumina carrier having large pores. The total pore volume of said carrier is in the range of 0.80˜1.20 ml/g (by mercury porosimetry method), the specific surface area in the range of 110˜200 m2/g, the peak pore diameter in the range of 15˜20 nm, and the bulk density in the range of 0.50˜0.60 g/ml. In the process of the invention, a physical pore-enlarging agent and a chemical pore-enlarging agent are added simultaneously during the mixing of the pseudoboehmite to a plastic mass, then extruding, drying, calcining, the carrier is obtained, then impregnating with active components by spraying onto the carrier, after drying and calcining, the catalyst is obtained.