The present invention relates to a gas-solid separation device specially adapted to the external risers of catalytic cracking units. The device comprises a pipe (19) forming substantially an angle of 90° with respect to a riser (2), said pipe (19) dividing into two tubular sections (4) forming between them an angle 2*γ, γ being between 5° and 85°. This device simultaneously makes it possible to channel the stripping gases and improves the overall efficiency of the separation by virtue of better control of the contact time. The present invention also relates to a catalytic cracking process using said gas-solid separation device.