METHOD OF HYDROGENATION REACTION

Disclosed is a heterogeneous catalytic hydrogenation process comprising hydrogenating a substance to be hydrogenated under trickle flow condition using a reaction tower charged with a solid catalyst, in which hydrogen gas and a liquid phase containing the substance to be hydrogenated are made to flow co-currently downward from above, wherein dynamic liquid phase holdup amount per unit catalyst exterior surface area of the catalyst charged in the reaction tower is 0.005 x 10 to 0.14 x 10 m /m and the catalyst has a catalyst strength of 1.0 Kg or more, as determined by the following formula catalyst strength = A-2 sigma wherein A represents a mean value of minimum strengths of 100 catalyst samples measured according to the method described in "Test method for crushing strength" of JIS Z-8841-1993" and sigma represents a mean standard deviation.