Patent classifications
C07C2/54
Process and device for continuous flow side-chain alkylation
A process and a device for continuous flow side-chain alkylation which relate to the technical field of organic synthesis. In this process and the device for continuous flow side-chain alkylation, an ibuprofen raw material is prepared with alkylbenzene as a raw material. This raw material alkylbenzene is easily available and has a low cost, and is suitable for scale-up production. Moreover, an entire preparation process adopts continuous chemical synthesis, and a reaction time of each stage can be precisely controlled, which is beneficial to control a total reaction time and reduce an amount of impurities produced. In this way, a purity and a yield of the ibuprofen raw material are improved. In summary, a continuous synthesis method for side-chain alkylation of alkylbenzene provided by the present disclosure shows a low cost and a high yield.
Continuous mixing reactor and method of use
A continuous mixing reactor has an outer shell having a cylindrical portion with a central section and two opposite conical end sections; a circulation tube within the shell so that an annular passage forms between the shell and the circulation tube; an impeller within and positioned adjacent to one end of the circulation tube; and heat exchange means penetrating the outer shell and extending into the end of the circulation tube opposite the impeller. The outer shell has a hydraulic head forming one end of the shell, a heat exchange medium header at the opposite end of the shell. The circulation tube nearer the heat exchange medium header terminates at or downstream from a tangential plane extending through the shell at the intersection of the central section and the conical end section of the cylindrical portion of shell. The reactor is useful in an alkylation process.
Catalyzed Alkylation, Alkylation Catalysts, and Methods of Making Alkylation Catalysts
Improved alkylation catalysts, alkylation methods, and methods of making alkylation catalysts are described. The alkylation method comprises reaction over a solid acid, zeolite-based catalyst and can be conducted for relatively long periods at steady state conditions. The alkylation catalyst comprises a crystalline zeolite structure, a Si/Al molar ratio of 20 or less, less than 0.5 weight percent alkali metals, and further having a characteristic catalyst life property. Some catalysts may contain rare earth elements in the range of 10 to 35 wt %. One method of making a catalyst includes a calcination step following exchange of the rare earth element(s) conducted at a temperature of at least 575 C. to stabilize the resulting structure followed by an deammoniation treatment. An improved method of deammoniation uses low temperature oxidation.
Propylene oligomerization processes with enhanced olefinic yields
In one embodiment the application pertains to a process which provides longer chain and less isomerized (more linear molecules). A propylene-derived olefin mixture is reacted under suitable conditions to form a mixture of oligomers in the presence of a catalyst comprising alkyl aluminum halide complex. A suitable alkyl aluminum halide complex comprises ethyl aluminum dichloride bis(2-chloroethyl) ether complex which may be used with a tert-butyl chloride or other initiator.
Propylene oligomerization processes with enhanced olefinic yields
In one embodiment the application pertains to a process which provides longer chain and less isomerized (more linear molecules). A propylene-derived olefin mixture is reacted under suitable conditions to form a mixture of oligomers in the presence of a catalyst comprising alkyl aluminum halide complex. A suitable alkyl aluminum halide complex comprises ethyl aluminum dichloride bis(2-chloroethyl) ether complex which may be used with a tert-butyl chloride or other initiator.