Anonymous
It is not possible to collect physical samples at different heights in the riser in an industrial unit. The riser in a commercial unit does not have any sample collectors. Products are collected after fractionation, both in the main fractionator or in the gas concentration unit.
The only way in which you could simulate what you want to study is through rigurous process modelling or at small scale, in an FCC pilot plant with a riser specially designed to collect samples at different heights or using several reactors of different heights