In a variety of reactions in the chemical industry, eggshell catalysts with a thin active layer are applied; they are often crushed for laboratory testing. The destruction of the shell can be avoided by a special reactor design. The presented advanced TEMKIN reactor is a further development of the reactor system for testing eggshell catalysts on the laboratory scale published by Temkin and Kul'kova in 1969. It is suitable for kinetic studies and for the detailed investigation of deactivation processes, as shown on the example of selective hydrogenation of acetylene.