Abstract: A catalyst element is described which is intended for use in a reactor for a chemical reaction where a lyophobic fluid is contacted with a lyophilic fluid for a reaction in the presence of catalyst in said element. The essential feature of the elements is that it is in the form of a porous lyophobic, e.g. hydrophobic, body which has a pore size essentially below 20 .mu.m, and is provided with a surface layer having a thickness of at most 100 .mu.m of lyophilic, e.g. hydrophilic, catalyst particles with a size essentially below 50 .mu.m, across part of its periphery only, said catalyst layer having been formed by sintering and/or pressing the catalyst particles into the porous lyophobic body.Preferable shapes of said catalyst element are a plate or a so-called packing element.Furthermore, a process for the preparation of said element is disclosed, which comprises adhering a surface layer of lyophilic catalyst to part of the periphery of a porous lyophobic body by sintering and/or pressing.