Solvent batch operations

Pan. Indirect type, batch operation Atmospheric or vacuum. Suitable for small batches. Easily cleaned. Solvents can be recovered. Material agitated while dried See comments under Liquids See comments under Liquids See comments under Liquids Suitable for small batches. Easily cleaned. Material is agitated during drying, causing some degradation Not applicable Not appbcable Not appbcable... 

Consider the case of the production of peroxy esters (e.g. tert-buty] peroxy 2-ethyl hexanoate), based on the reaction between the corresponding acid chloride and the hydroperoxide in the presence of NaOH or KOH. These are highly temperature sensitive and violently unstable, and solvent impurities are detrimental in their applications for polymerization. Batch operations to produce even 1000 tpa will be unsafe. A continuous reactor can overcome most of the problems and claims have been made for producing purer chemicals at lower capital and operation cost the use of solvent can be avoided. Continuous reactors can produce seven to ten times more material per unit volume than batch processes. Since the amount of hazardous product present in the unit at any given time is small, protective barrier walls may be unneccessary (Kohn, 1978). 

An unsteady-state component mass balance, Eq. (20-68), can be written for batch operation by assuming a uniform average retentate concentration c, within the system. Assuming a constant solvent concentration and a 100 percent passage, the solvent balance becomes Eq. (20-69). 

Microautoclave data was also obtained with Wilsonville Batch I solvent utilizing Indiana V coal. Batch I solvent was obtained from Wilsonville in mid-1977. Other batches of recycle solvent were received later. Batch I solvent had inspections most like the Allied 24CA Creosote Oil used for start-up at the Wilsonville Pilot Plant. Succeeding batches of solvent received by CCDC showed substantial differences, presumably due to equilibration at various operating conditions. As the Wilsonville solvent aged and became more coal derived, the solvent aromaticity decreased with an increase in such compounds as indan and related homologs. The decrease in aromaticity has also been verified by NMR. A later solvent (Batch III) also showed an increase in phenolic and a decrease in phenanthrene (anthracene) and hydrogenated phenanthrene (anthracene) type compounds. 

Table III shows the results of operating the SRT unit in the hydrogen donor mode (catalytically hydrogenated solvent) with and without the addition of Light SRC to the distillate solvent Batch I solvent was used in Run 9 A blend of Batch VI solvent and Light SRC, 70/30 weight ratio, were catalytically hydrogenated as the feed to Runs 1 and 3 The hydrogen donor capability of the solvents were measured by the Equilibrium microautoclave tests These bench-scale SRT results are rather extraordinary in respect to increased distillate yields and improvement in unit operability with addition of Light SRC In Table III the integrated yields refer to the combination of liquefaction, CSD, and catalytic hydrogenation of the solvent ...

The solvent method may also be performed either by continuous (in cascades) or by batch operation. Continuous techniques in particular have gained considerable technical importance. A phthalonitrile/copper chloride solution is typically treated at 120 to 140°C in a flow tube furnace and the temperature subsequently increased to 180 to 250°C. The entire process requires approximately 1.5 to 2 hours and affords the pigment in practically quantitative yield. The excellent purity of the product eliminates the need for additional purification with dilute acid or base prior to finishing, a procedure which plays a major role in the baking process. These... 

Extractive distillation is usually more desirable than azeotropic distillation since no large quantities of solvent have to be vaporised. In addition, a greater choice of added component is possible since the process is not dependent upon the accident of azeotrope formation. It cannot, however, be conveniently carried out in batch operations. 

For batch operation (see Sect. 2.3.4), the limiting current density is going to zero for increasing degree of conversion (see reactant 1 in Fig. 1). Here, the galvanostatic operation may only be acceptable if exclusively unproblematic side reactions occur, such as water electrolysis as solvent decomposition. In all other cases, better results can be expected using the potentiostatic operation (see next section). 

An epoxy compound is to be condensed with an amine at 40 °C. The reaction is fast and will be performed in a 4 m3 reactor cooled with water. The process is semi-batch operation, the solvent 800 kg isopropanol, 240 kg of the epoxy compound are initially charged, and 90 kg of amine are added at a constant rate during 45 minutes, while the temperature is not allowed to surpass 40 °C. 

Vacuum shelf. Indirect type, batch operation Not applicable Applicable for small-batch production Suitable for batch operation, small capacities. Useful for heat-sensitive or readily oxidiz-able materials. Solvents can be recovered See comments under Pastes and Sludges Suitable for batch operation, small capacities. Useful for heat-sensitive or readily oxidiz-able materials. Solvents can be recovered. See comments under Granular solids Not applicable See comments under Granular solids... 

Pollution Prevention Technologies Practices Batch operations Equipment parts cleaning Reactor design operation High-value waste Water usage Organic solvents pH control... 

Studies have shown that the type of solvent used has effect on the particle size, morphology and biological activity of the molecule [19, 20]. The principal disadvantage of this process is the lack of control over particle formation. This has been observed to be true in batch operating conditions because the level of saturation is not maintained. 

In a batch operation, an ion exchange resin in the desired ionic form is placed into a stirred reaction vessel containing the solution to be treated. The mixture is stirred until equilibrium is reached (about 0.5 to 3 hours). Then the resin is separated from the liquid phase by rinsing with the eluting solution. An additional step may be required to reconvert the resin to the regenerated form if this is not done by the eluting solvent. The cycle may then be repeated. 

Example 1—Dry 100 lbs. ofwetcake with an/ /fto/ volatiles content ofl5%(wetbasis) dovmXodiflnalvolatilescontent of less than 1 %. This will be achieved in a batch operation for lot identification, GMP and high quality standards. The loose bulk density of the wet cake is 45 lbs../ft. and the loose bulk density of the diy powder is 12 Ibs./ft. The temperature limit of the product is 145°F and the feed material is wet with ethanol. The product is a pharmaceutical which will be a finished product. The solvent is to be recovered for reuse, and its physical properties can be found in a handbook of hydrocarbons. The product is freeflowing in the dry state, but very tacky and pasty in the wet state. 

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