Autoclave reaction

Autoclave reactions involving ethylene oxide with alkanethiols or an (unspecified) alcohol went out of control and exploded violently. Similar previous reactions had been uneventful [1], An arenethiol was being reacted with ethylene oxide under catalysis by a fraction of a percent of sodium hydroxide (solid) dissolved in the thiol to which the oxirane was slowly charged. After an initial exotherm a white solid precipitated, the exotherm died away and later resumed, with dissolution of the solid, the reaction then running out of control from the backlog of charged oxirane [2],... 

The traditional syntheses of metal carbonyls by autoclave reactions is time-consuming and causes numerous problems in terms of radiation protection when radioactive materials (such as 186,188 or 99>99 +c) are used. However, a protocol which produces rhenium (I) tricarbonyl... 

Procedure. One hundred grams of coal liquid was combined with a predetermined amount of presulfided Co-Mo-Al catalyst and charged to the autoclave. Reaction temperature for the runs varied from 360 to 435°C, depending on the run. A stirring setting of 1000 rpm was used, and the initial total pressure was varied from 1500 (10.4 MPa) to 2500 (17.3 MPa) psig. The heat-up rate was about 12 to 20°C/min, thus requiring a total heat-up time of about 20-25 minutes. 

Fig. 9. Splitting of decahydronaphthalene in the presence of coronene. Autoclave reaction conditions Temperature, 425°C. Hydrogen pressure, 600-700 atm. Catalyst, 300 cc. (800 g.) WS2 Charge, 1000 ml. decahydronaphthalene and 0-600 g. coronene.

Catalyst (0.5 g), naphthalene (10 mmol), terf-BuOH (20 mmol), cyclohexane (100 ml), 2 h autoclave reactions at 160 °C. b A synthetic mesoporous material. 

Following this study, we found that the optimum conditions for maximising the yield while retaining selectivity involved two successive 1 h autoclave reactions at 180 °C, using HM (4.0 g, Si/Al ratio 17.5), /er/-butanol (80 mmol) and cyclohexane (10 ml) for an initial 10 mmol of naphthalene. Under these conditions, a 2,6-di-tert-butylnaphthalene yield of 50 % and a 2,6/2,7 ratio of 58.5 were achieved after the first reaction, and a 60 % yield with a ratio of 50.6 after the second stage. The optimised result is compared with the most selective literature result in Table 4. 

The experiments at 250°-300°C were performed in a 300 ml stirred autoclave. Reaction times refer to the "time at temperature." Some 30 min. was required to bring the autoclave and its contents to temperature and about 15 min. was required to cool it again to ambient temperatures. 

Formation of pyrazines by high-temperature autoclave reaction of a-halogenomethyl ketones with ammonia. 

In analogous autoclave reactions, COFj will react with COBr2 or COXF (X = Cl or Br) to produce CBr2F2, CCIF3 or CBrClFj, respectively [902,905], but none of them cleanly. 

Caution. If the autoclave reaction is performed at <200°, a lower yield ( 30g) is obtained, and, upon distillation, a white, pyrophoric solid is deposited in the condenser. 

Suggest why KF is a better reagent than NaF for replacement of chlorine in organic compounds by fluorine by the autoclave reaction ... 

TEM is highly suited to imaging nanoscale materials. For example, the TEM image opposite illustrates hollow spheres of boron nitride, formed from an autoclave reaction between BBrs and NaNs ... 

The stable product from the autoclave reaction between P4O10 and liquid NH3 at 40-50°C, will undergo further condensation at 110°C to give a polymer. 

With the pressurized hydrolysis technology, water under high temperature and high pressure is applied to hydrolyze and break the crosslinks of the paint film, and then a kneading extruder is used to convert the decomposed film into particles and disperse them in the TP resin. Two types of the processing system have been developed. One is the autoclave reaction and screw extrusion processing system (batch system), and the other is the twin screw reactive extrusion processing system (continuous system). 

Autoclave reaction and screw extrusion processing system [1, 2, 3]... 

Reinvestigation of the CsF-initiated autoclave reaction between perfluoro-AT-fluoropiperidine and perfluoropropene at elevated temperatures has shown that the product formerly believed to be petfluoro-( -iso-propylpiperidine) (24), and formed via the 5n2 process... 

In order to determine if the black material added to the autoclave was in fact chromium metal or a mixture of Cr(II) salts and potassium, the following experiments were carried out. The black material obtained from the reduction of CrCls BTHF with potassium in benzene was repeatedly extracted with THF to remove and to determine soluble chromium(ll) salts. Also the amount of unreacted potassium was determined by repeated extraction of the black material with alcohol and water and subsequent acidic titration of the extracts. From these two determinations, it was established that a minimum of 58% of the Cr(CO)e formed in the autoclave reaction originated from chromium(O). In a separate experiment, the black material was extracted repeatedly with THF to remove all the soluble chromium salts and was then treated with CO under the same conditions as in the previous reactions. The yield of Cr(CO)6 was 30% based on the material placed in the autoclave. Thus, it is clear that Cr(0) is produced in the reduction, and this Cr(0) will react with CO to yield Cr CO)e- It is difficult to determine the exact amount of Cr(CO)6 which originated from Cr(0) in the black powder due to its instability. Thus, excessive manipulations of the black powder even under argon or very long reduction times in the generation of the black powders seem to deactivate the Cr(0). 

Risk reduction model for a polymer autoclave reaction runaway... 

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