Continuous preparation

Volume VI. Preparation and Assay of Enzymes (Continued) Preparation and Assay of Substrates Special Techniques... 

Figure 1. Aerosol process configuration for the continuous preparation of metal oxides by the High Temperature Aerosol Decomposition (HTAD) Process.

Fig. 1.1.2 Schematic presentation of the plug-flow type of a reactor for the continuous preparation of monodispersed colloids by precipitation from homogeneous solutions. (From Ref. 31.)...

In some cases a second (or further) reaction step(s) can be added in order to adjust the particle size, to increase the mass fraction, or to modify the surface of the silica particles prepared in the first step. The process proceeds in a similar way as already described for the first continuous preparation step however, mixture A is now substituted by the previously prepared silica dispersion, and mixture B is replaced either by a further amount of TEOS or by various organotrialkoxysilanes (mixture C). 

The continuous preparation of lead styphnate can be carried out in the same equipment as for the manufacture of lead azide (Fig. 50) after previous cleaning of the apparatus and exchanging the flowmeters. 

An important advantage of two-dimensional methods is the solitary migration of each fraction on its own path. In contrast with unidimensional or zone electrophoresis where each fraction migrates its own distance but over a common path, no contamination of fractions is possible (Fig. 40). If the substrate is sufficiently long and wide and a high intensity electrical field is applied, it becomes possible to separate fractions reasonably completely from each other. If the physical forces involved are deployed skillfully, the electrical field can be driven up so that rapid and wide separations are obtained. This point is especially important in star electrophoresis, whereas in collecting electrophoresis mastery of the physical forces provides an excellent continuous preparative tool. 

For technical purposes a partial conversion with an easy to perform workup is feasible. Therefore, a series of electrolyses were performed to a specific conversion (Fig. 5.11). During electrochemical conversion the amount of 13 increases in a linear fashion up to 0.3 F mol-1 1. Subsequently, side reactions appear and limit the amount of isolated 13. For an efficient process and high-quality product, a partial conversion of about 30% is reasonable. Since excess of 12 is easily recovered, virtually no loss of material occurs, creating a good basis for a continuous preparation of 13. 

Pentane-1,2-diol is an important intermediate for the production of fungicides125 and can be continuously prepared by reacting pent-l-ene with a solution of perpropionic acid in benzene, and subsequent hydrolysis of the epoxide.126 The diol yield of 92% from the alkene is much higher than with performic acid (Figure 3.26).116... 

Other future FFF developments may address the highly desired continuous preparative FFF fractionation apart from SPLITT channels. This requires the following experimental conditions ... 

Welzel T, Meyer-Zaika W, Epple M (2004) Continuous preparation of functionalised calcium phosphate nanoparticles with adjustable crystallinity. Chem Commun 10 1204-1205... 

H. J. Kwak, Method and system for continuously preparing gasoline, kerosene and diesel oil from waste plastics, US Patent 6866830, 2005. 

Korean Patent 0191075 Method and System for Continuously Preparing Gasoline, Kerosene and Diesel Oil From Waste Plastics Patent issued January 1999. 

HI-TEK POLYMERS Textile Industry Products(Continued) Preparation, Scouring and Bleaching Assistants(Continued) PROGASOL 1 ... 

Hydroxy ketones—Continued preparation, from acetylenic cat-binols, 341... 

Imino esters—Continued preparation, 483, 634 preparations listed in table 76, 637 pyrolysis to amides, 376 Imino ethers, see Imino esters Imino ketones, preparation, 730 jS-Iminonitriles, hydrolysis, 351 preparation, 730 Indoles, alkylation, 836... 

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