TWO-STAGE PROCESS OF OBTAINING PROPIONIC ACID Russian patent published in 2017 - IPC C07C53/122 C07C51/14 C01B3/16 B01J31/04 B01J21/02 B01J23/46 B01J23/75 

FIELD: chemistry.

SUBSTANCE: two-stage continuous process of preparing propionic acid is provided; it comprises the step of hydrogenating the carbon dioxide in the synthesis gas in the presence of a catalyst comprising cobalt metal on the support as organometallic framework MIL-53 structure (Al), and a step of hydroxycarbonylation of ethylene with carbon monoxide and water in the presence of hydroxycarbonylation catalyst, which is a metallic rhodium on a carrier in the form of organometallic framework MIL-53 structure (Al), and the process is conducted in a flow 2- tray reactor at a pressure of 40-80 atm by contacting the fixed catalyst bed located on the top shelf and the reactor heated to a temperature of 500°C, with a raw material mixture of H₂ and CO₂ at a volumetric feed rate of gas feedstock 500-1000 h^-1, followed by mixing of the produced gas containing CO-H₂-CO-H₂O mixture heated to 500-520°C with cold ethylene fed into the inter-bed space and the resulting gas mixture at a ratio of CO:H₂O:C₂H₄ close to 1:1:1 is fed to the lower shelf of the reactor and is contacted at a temperature of 140-200°C with the hydroxycarbonylation catalyst therein. The process is carried out at a volume ratio of H₂:CO₂ in the gas feedstock of 0.8-1.2, and use catalysts having a size of 2-4 nm metallic particles with a cobalt content of 10 wt % rhodium and 5-15 wt %.

EFFECT: propionic acid increase in the yield and selectivity of its formation, while simplifying the process technology and reducing energy consumption, provides a recycling method of the greenhouse gas.

3 cl, 3 dwg, 1 ex