Slurry reactor immersion

Catalytic hydrogenation is typically carried out in slurry reactors, where finely dispersed catalyst particles (<100 (tm) are immersed in a dispersion of gas and liquid. It has, however, been demonstrated that continuous operation is possible, either by using trickle bed [24] or monoHth technologies [37]. Elevated pressures and temperatures are needed to have a high enough reaction rate. On the other hand, too high a temperature impairs the selectivity of the desired product, as has been demonstrated by Kuusisto et al. [23]. An overview of some feasible processes and catalysts is shown in Table 8.1. 

An example of immersion stabilization is nickel catalysts for the hydrogenation of edible oils. ° The nickel catalyst is a powder that is used in batch slurry reactors. Since nickel is pyrophoric, the material must be stabilized for shipment to end user plants. After reduction in a fluid bed furnace, the catalyst is dropped under a N2 atmosphere into melted, fully hydrogenated edible oil. The thick slurry is then pastillated into droplets and solidified at room temperature. The result is small droplet-shaped solids of reduced nickel catalyst embedded in hardened edible oil. When used at the edible oil facility, the fully hydrogenated oil readily... 

Two semi-batch reactors were used in this study. The slurry reactor was a 0.5-liter jacketed glass reactor. The slurry reactor was operated at atmospheric pressure. The gas-phase reactor was a one-liter stainless steel reactor which was immersed in an oil bath for temperature control. The solids in the gas-reactor were kept in suspension by an AE MagneDrive stirrer. 

C. 1275ml of aq 1 molar Hg (ic) nitrate soln mixed with 22ml of 70% nitric acid soln Procedure Equipment is set up as shown In Fig 1, except that the immersion coil is not used in the reactor. Soln A was prepd in the reactor by adding 80° w to Cuen2(NT)2. Soln B is added over 30 mins. When a green slurry is not... 

Photocatalytic reactions are promoted by solid photocatalyst particles that usually constitute the discrete phase distributed within a continuous fluid phase in the reactor. Therefore, at least two phases, that is, liquid and solid, are present in the reactor. The solid phase could be dispersed (SPD) or stationary (SPS) within the reactor. SPD photoreactors may be operated with the catalyst particles and the fluid phase(s) agitated by mechanical or other means. Depending on the means of agitation, the photoreactor resembles that of slurry or fluidized bed reactors. In numerous investigations, an aqueous suspension of the catalyst particles in immersion or annular-type photo reactors has been used. However, the use of suspensions requires the... 

Two major types of slurry bubble column reactors are illustrated in Figure 12.17, one from Exxon [68] and the other from Sasol [69]. The reactor containing cooling coils immersed in the slurry is the one that is the most frequently encountered. The concept of one type of reactor patented by Exxon [68] has many similarities to the ARGE fixed-bed reactor except the fixed... 

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