APPARATUS AND REACTION PROCEDURES

APPARATUS AND REACTION PROCEDURES 2.4 INTERCHANGEABLE GROUND GLASS JOINTS... 

Apparatus and Procedure. The kinetic studies of the catalysts were carried out by means of the transient response method (7) and the apparatus and the procedure were the same as had been used previously (8). A flow system was employed in all the experiments and the total flow rate of the gas stream was always kept constant at 160 ml STP/min. In applying the transient response method, the concentration of a component in the inlet gas stream was changed stepwise by using helium as a balancing gas. A Pyrex glass tube microreactor having 5 mm i.d. was used in a differential mode, i.e. in no case the conversion of N2O exceeded 7 X. The reactor was immersed in a fluidized bed of sand and the reaction temperature was controlled within + 1°C. 

Apparatus. The apparatus and experimental procedure have been described (9). A static system was used with catalyst samples (normally 0.1 gram of hydrated material) in the bottom of the reaction vessel (volume 1 X 10" m ). The reaction was followed by periodically sampling the gas phase above the catalyst and analyzing by GLC techniques. 

An excess of molten SO3 is allowed to react with pure, finely powdered Te at room temperature. The reaction must be protected from moisture. The apparatus and the procedure are the same as for the analogous synthesis of S3O3 (p. 380). The product is dark-red a-TeSOg in order to obtain the light brown /3-modlflcatlon, this product is heated for a short time to about 80°C. 

One of the main tasks in the studies of solid-state reactions is the determination of the kinetics of the corresponding reactions. The technology of TA is often used to reveal the thermal behavior and thermal character of solid-state reactions, the primary aim is to establish the values of the apparent activation energy E and pre-exponential factor A in the Arrhenius equation, and to choose the most probable mechanism function f(a) of the reaction. The used mathematical apparatus and calculation procedures are quite varied, but they all are related to the mathematical analysis of thermogravimetric curves [6-8]. The analysis of these curves allows determining the mechanism of rate-controlled stage of the conversion, and the values of the kinetic parameters that characterizing it. 

Apparatus and procedure Closely similar to the preparation of tert.-Ci,H3MgCl, cyclohexyl-MgCl and cyclopentyl-MgCl (see Exp. 2). The yield (estimated from the results obtained from reactions with this reagent) is at least 90%. Here, too, it is essential to use M-butyl chloride which is free from butyl alcohol. 

The general reaction procedure and apparatus used are exactly as described in Procedure 2. Ammonia (465 ml) is distilled into a 2-liter reaction flask and to this is added 165mlofisopropylalcoholandasolutionof30g(0.195 mole) of 17/ -estradiol 3-methyl ether (mp 118.5-120°) in 180 ml of tetrahydrofuran. The steroid is only partially soluble in the mixture. A 5 g portion of sodium (26 g, 1.13 g-atoms total) is added to the stirred mixture and the solid dissolves in the light blue solution within several min. As additional metal is added, the mixture becomes dark blue and a solid (matted needles) separates. Stirring is inefficient for a few minutes until the mass of crystals breaks down. All of the sodium is consumed after 1 hr and 120 ml of methanol is then added to the mixture with care. The product is isolated as in Procedure 4h 2. After being air-dried, the solid weighs 32.5 g (ca. 100% for a monohydrate). A sample of the material is dried for analysis and analyzed as described in Procedure 2 enol ether, 91% unreduced aromatics, 0.3%. The crude product may be crystallized from acetone-water or preferably from hexane. 

Copper oxide, oxidation of CO over, 86 Coupled heterogeneous catalytic reactions, kinetics of, 1-49, see also Kinetics coupling through catalytic surface, 9-13 experimental studies, 22-49 apparatus and procedure, 25, 26 catalysts, 26-28... 

The present one-step procedure for preparation of 5,6-dihydro-2if-pyran-2-one is slightly modified from that described in the original paper.9 It is simpler and easier than the three-step method3 used in the past and represents the most convenient synthesis presently available. The present preparation of 2f/-pyran-2-one has several advantages compared to the alternatives mentioned above simplicity of apparatus and technique, mild reaction conditions, availability of reactants, and ease of product isolation. 

The experimental semibatch apparatus and procedure have been described in several places through the text of Wisseroth s publications ( 1, 7-9). so the details will not be repeated here. For nearly all of his work the reactor volume was one liter, temperature was 80 C, pressure was 30 atm (441 psia), and the feed was polymerization grade I assume that the reactor gas composition was 99% CsHgand 1% inerts. The range of catalyst loading was from 11 to 600 mg of TiCils per batch. The reaction time was varied from 0.5 to 6 hours. The weight ratio of alkyl-to-TiC 3 in the catalyst recipe was varied from 0.5 to 32. No data are reported from a continuous gas phase reactor. 

This preparation and oleoyl chloride (p. 66) illustrate the use of the general form of a laboratory-sized continuous reactor.6 This device has many advantages over the commonly used flasks (batch procedure). In particular, the short time of exposure to heat results in a better quality of product, as shown by less color, fewer side reactions, and better melting point, often unchanged by recrystallization. Furthermore, the unlimited capacity, very short reaction time, and use of concentrated solutions permit a larger output with no increase in size of apparatus and less delay required for removal of solvents. 

The index lists the names of compounds in two forms. The first is the name used commonly in procedures. The second is the systematic name according to Chemical Abstracts nomenclature. Both are usually accompanied by registry numbers in parentheses. Also included are general terms for classes of compounds, types of reactions, special apparatus, and unfamiliar methods. 

The details of the experimental apparatus and procedures are outlined in another paper (76). The reactor consisted of a quartz tube with an inside diameter of 18 mm which held the monolith or gauze pack. The reactor was operated at a steady state temperature which is a function of the heat generated by the exothermic reactions and... 

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