Stirred contained solids reactor

Table 4-4 summarizes the ratings of the various reactors. The CFSTR and the recirculating transport reactor are the best choices because they are satisfactory in every category except for construction. The stirred batch and contained solid reactors are satisfactory if the catalyst under study does not decay. If the system is not limited by internal diffusion in the catalyst pellet, larger pellets could be used and the stirred-contained solids reactor is the better choice. However,... 

Figure 4-20 shows a typical design of a stirred contained solids reactor. Here, the catalyst particles are mounted in the paddles that... 

Figure 4-20. Stirred contained solids reactor. (Source V. W. Weekman, Laboratory Reactors and Their Limitations, AlChEJ, Vol. 20, p. 833, 1974. Used with permission of the AlChEJ.)...

Stirred contained solids reactors. [Reproduced from V. W. Weekman, Jr., AIChE J.,... 

Figure 5-16 Stirred contained solids reactor. (From V. Weekman, AJChE J. 20, 833, (197 4) with permission of the AIChE, Copyright 1974 AIChE. All rights reserved.]...

P5-14b The ethane hydrogenoiysis over a commercial nickel catalyst was studied in a stirred contained solids reactor. 

The effect of physical processes on reactor performance is more complex than for two-phase systems because both gas-liquid and liquid-solid interphase transport effects may be coupled with the intrinsic rate. The most common types of three-phase reactors are the slurry and trickle-bed reactors. These have found wide applications in the petroleum industry. A slurry reactor is a multi-phase flow reactor in which the reactant gas is bubbled through a solution containing solid catalyst particles. The reactor may operate continuously as a steady flow system with respect to both gas and liquid phases. Alternatively, a fixed charge of liquid is initially added to the stirred vessel, and the gas is continuously added such that the reactor is batch with respect to the liquid phase. This method is used in some hydrogenation reactions such as hydrogenation of oils in a slurry of nickel catalyst particles. Figure 4-15 shows a slurry-type reactor used for polymerization of ethylene in a sluiTy of solid catalyst particles in a solvent of cyclohexane. 

Effect of Acyl Donors. TTie synthesis of glucose fatty acid esters was investigated with continuous by-product removal in a stirred-tank membrane reactor by azeotropic distillation using EMK containing 20% hexane as reaction solvent and different fatty acids as acyl donors. From previous studies on the lipase-catalyzed synthesis of glucose esters in a solid-phase system (17,19,22,23), it was already known that the fatty acid chainlength had a considerable influence on product formation. This was due... 

A well-stirred reactor containing solid catalysts can be modelled as a perfect stirred tank reactor, that is, concentration is the same everywhere inside the reactor. When such catalysts are very small, the diffusional resistance inside the catalyst can be ignored. The catalyst is slowly... 

Processes for precipitation of solid products from dissolved reactants are almost always carried out in stirred tanks. The reactors are operated either semi-batchwise or continuously. In both operation modes, one reactant is added to a stirred solution containing an excess of the other reactant. The functions of the stirrer are mixing of the reactants, suspension of the formed solid particles, and promotion of heat transfer to the wall. 

A reactor containing 5 ml of 95% nitric acid was cooled to between 0 and 5°C in an ice/water bath and then treated with the step 3 product (200 mg) and the mixture stirred for 15 minutes while maintaining the temperature below 5°C. The solution was then added dropwise to 60 ml of water, cooled, and the nitrated product isolated as a white, oily solid precipitate. Water was decanted, the precipitate washed with water, and in vacuo at 50°C for 2-3 hours, and the product isolated as a pale yellow viscous liquid in 80-90% yield. 

A reactor was charged with 1,10-diaminodecane (20 mmol) dissolved in 170 ml of /V, /V - d i m e t h I fo rm amide containing pyromellitic anhydride (20 mmol) and the mixture stirred at ambient temperature for 60 hours. It was then precipitated in 4 liters of acetone/hydrochloric acid, 1 4, respectively, and collected. The solid was washed with aqueous hydrochloric acid solution and acetone and then heated and dried in vacuum at 60°C for 36 hours and 7.65 g of product isolated as a white powder. 

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