Rhodium Catalyst for Low Pressure Oxo Synthesis and Spent Rhodium Catalyst Liquid Recovery

II Rhodium Catalyst for Low Pressure Oxo Synthesis (ROPAC)

In recent times, basic organic systhesis and the synthesis of plastics, synthetic rubber, and synthetic fiber were based on olefin and alkyne chemistry, and organic metal complex catalysts are extensively used in these syntheses. Among these syntheses, hydrofomylation is an important way for carrying out the synthesis of aldehydes and alcohols in industries. The hydroformylation of olefins is also called oxo synthesis, and means the production of aldehydes by reacting olefins with syngas in the presence of catalyst. The aldehydes and alcohols produced this way are largely used as plasticizers, textile additives, surfactants, solvents, and spices.

The most important element of oxo synthesis is Rhodium complex catalysts. Among these catalysts, oil-soluble acetylacetonatocarbonyltriphenylphosphinerhodium (I) (ROPAC) stands out by featuring weak isomerization, low hydrogenation activity, high selectivity, and fast reaction, and is widely applied in the propylene hydroformylation units domestically and internationally. Currently, most of hydroformylation catalysts used in domestic units are imported. The manufacture of Rhodium catalysts and the recovery technologies for spent Rhodium catalysts are operated and controlled by foreign companies (Umicore and John and Matthey), resulting in high costs for domestic butanol/octanol units.

After long time hardwork and continuing efforts, Beijing Gaoxin Lihua Technology Co., Ltd. successfully developed oil-solulbe Rhodium phosphine catalyst (acetylacetonatocarbonyltriphenylphosphinerhodium (I)) named ROPAC, which pioneers OXO synthesis catalysts in China. The manufacture technology of ROPAC has the advantages of simple and reasonable preparation, good availability of feedstocks, mild reaction conditions, high utility ratio of Rhodium, etc. Beijing Gaoxin Lihua Technology Co., Ltd. developed effective proprietary technologies for the mass production of noble metal organic compounds. The proprietary technology includes mass transfer, product separation, product purification, etc. The commercial applications of ROPAC demonstrate that, in propylene oxo synthesis, the performance of ROPAC is equal to or better than that of imported products in reaction rate and butylaldehyde selectivity. Therefore, ROPAC can substitute for imported products. 

III Rhodium Phosphine Complex Catalyst BC-2-007

Electronic Microscope Photo for Low-Pressure OXO Synthesis Catalyst BC-2-007 (100μm)

IV Operation Conditions for Catalyst ROPAC

IV 1 Operation conditions

IV 1.1 Facility: OXO synthesis unit,

IV 1.2 Working medium: Syngas, propylene,

IV 1.3 Temperature: 80~110℃, 120℃ (max.) at service life end；

IV 1.4 PPh3 concentration: 11%min, and 13%max.

IV 2 Major specifics

IV 2.1 Propylene feedstock composition

IV 2.2 Syngas specifics

Rhodium Metal Recovery

from Spent Rhodium Catalyst Liquid

There are two types of methods for recovering metal Rhodium from spent Rhodium catalysts. One type covers various wet mehods, the other type includes various combustion methods. The wet methods includes extraction, precipitation, oxidation-distillation, ion-exchange/adsorption, chemical activation, etc. Beijing Gaoxin Lihua Technology Co., Ltd. developed several Rhodium recovery methods targeting various spent Rhodium catalysts. The purity of the Rhodium powder recovered through theses methods is no smaller than 99.95%.