Abstract: A mixed-bed catalytic system and its activation for direct synthesis of dimethyl ether from synthesis gas are described, comprising a catalyst for methanol synthesis and the zeolite ferrierite in its acid form as the methanol dehydrating component, the two being mixed physically in the form of powder of defined granulometry or as pellets. Another object of the present invention is a process for production of the acid form of the zeolite ferrierite. Another object of the present invention is a process for direct synthesis of dimethyl ether from a synthesis gas, using the catalytic system of the present invention.

Abstract: A process to reduce acidity of hydrocarbon mixtures (1) is described, that includes sending a hydrocarbon stream to a Microwave Treatment Unit (MTU), with a fixed stream or mud bed of microwave absorbent materials, pure or in mixtures, such as coke fines, spent catalysts that have already been used in FCC units or hydrotreatment (HDT) in a refinery, or even new catalysts which may be sulfided or not, under processing conditions.

Abstract: A modified alumina is useful as metals passivator in fluidizable catalytic cracking catalysts. The modified alumina is prepared from a hydrated alumina, e.g., gibbsite, which is reacted with a low-molecular weight organic acid, e.g., acetic acid, forming aluminum salts. Calcination of the modified alumina results in decomposition of the aluminum salt.

Abstract: A system for separating catalyst particles in the catalytic cracking of reacted hydrocarbons includes an unconfined cyclone device made up of a diplegless cyclone opening directly into a large volume separator vessel downwardly through a mouth and upwardly through the annular space between concentric pipes. The concentric pipes are connected to the other components of the system as well as the hydrocarbon fluid catalytic cracking process carried out in the system.