METHOD FOR CONTINUOUS TWO-STEP HYDROFORMYLATION OF C3, C4 OLEFINS AND PROCESS APPARATUS THEREFOR Russian patent published in 2015 - IPC C07C47/02 C07C45/50 B01J19/24 

FIELD: chemistry.

SUBSTANCE: method includes feeding into a first stage reactor fresh olefin and synthesis gas, a recirculating catalyst solution containing a rhodium complex, organophosphorus ligands, product aldehydes and heavy by-products; performing a hydroformylation chemical reaction; separating from the gas-liquid outlet of the first stage reactor unreacted synthesis gas, followed by dividing the remaining part into product aldehydes, a hydrocarbon fraction containing an unreacted olefin and a catalyst solution and recirculating the latter into the first and second stage reactors; feeding the hydrocarbon fraction and unreacted synthesis gas into the second stage reactor; the method characterised by that conversion in reactors of both stages is kept in the range of 75…92% with respect to the fed olefin, and the ratio of the amount of the catalyst solution fed into the first stage reactor to the amount of the catalyst solution fed into the second stage reactor is kept in the range of 3…10; wherein during the hydroformylation process, conversion of heavy products in the recirculating catalyst solution is kept in the range of 80-95% by removing part of the catalyst solution, thereby providing constant concentration of rhodium by feeding a fresh rhodium precursor, and regioselectivity of the process on linear aldehydes is kept higher than 90% by constantly feeding a diphosphite ligand. Inert gases and gaseous by-products are removed from the outlet of the second stage hydroformylation reactor, and all of the remaining catalyst-containing liquid phase is fed into the first stage reactor, wherein separation of product aldehydes from the catalyst solution contained in the outlet of first stage reactor is carried out in a film evaporator, which is blown with a synthesis gas stream separated from the outlet of the first stage reactor. The catalyst solution separated in the evaporator, when removing from the blowing area with synthesis gas, is cooled immediately. The invention also relates to a process apparatus for realising the disclosed method.

EFFECT: invention reduces loss of the feed stock, increases specific output of the end product and increases specific capacity of the reaction volume.

2 cl, 1 dwg, 2 tbl, 5 ex