Autoclaves, agitated

The following details for the commercial manufacture of poly(vinyl methyl ether) have been made available. Agitated vinyl methyl ether at 5°C is treated over a period of 30 minutes with 0.2% of catalyst solution consisting of 3% BF3 2H20 in dioxane. When the reaction rises to 12°C the reaction is moderated by brine cooling. Over the next 3-4 hours further monomer and catalyst is added. The autoclave is then closed and the temperature allowed to rise slowly to 100°C. 

A shaker tube equipped with a 1200-atm. rupture-disk assembly was used by the submitters. The checkers used a 1270-ml. stainless steel rocking autoclave fitted with a thermocouple well that extended into the reaction mixture and a stainless steel 5000-p.s.i. rupture disk. The agitation rate was 58 cycles per second. Attempts to use a magnetically stirred autoclave were unsuccessful. 

Over half the ethylene pressured into the autoclave dissolves in the piperidine. It is essential to agitate the piperidine during the pressuring operation so that the piperidine will become saturated with ethylene, for otherwise there will not be enough ethylene for the reaction. 

An autoclave (Note 1) is charged with 200 g. (1.28 moles) of 2,3-dimethylnaphthalene (Note 2), 940 g. (3.14 moles, 23% excess) of sodium dichromate dihydrate, and 1.8 1. of water. The autoclave is closed, heated to 250°, and shaken continuously at this temperature for 18 hours. The autoclave is cooled with continued agitation (Note 3), the pressure is released, and the autoclave is opened. The contents are transferred to a large vessel (Note 4). To effect complete transfer, the autoclave is rinsed with several 500-ml. portions of hot water. Green hydrated chromium oxide in the reaction mixture is separated on a large Buchner funnel and washed with warm water until the filtrate is colorless. The combined filtrates (7-8 1.) are acidified with 1.3 1. of 6N hydrochloric acid. The acidified mixture is allowed to... 

Example 1. Alkaline Hydrolysis of Nylon-6,6 in Isopropanol.9 Isopropanol (209 parts), 267 parts of water, 54 parts of 97% sodium hydroxide, and 100 parts of nylon-6,6 were charged to a 1-gal stainless steel autoclave. Under an atmosphere of nitrogen, the charge, which weighed 1060 g, was heated in the autoclave to 180°C for 1.5 h with constant agitation and then cooled. A clear two-phase liquid was obtained which had an alcoholic upper phase and an... 

Agitator autoclave tests can be used as screening tests despite the more intensive localized corrosion attack and the generally greater erosion rates. This test method elucidates the influences of certain test parameters including temperature, H2S/CO2 ratio, and flow [564]. 

Agitated autoclaves These systems are used for leaching under conditions of elevated temperatures and pressures... 

A gaseous alkene was passed into a cooled autoclave containing the complex, initially with agitation, and later without. Later, when the alkene was admitted to a pressure of... 

The process is run in a semi-batch mode, and multiple reactors are used. There are several possible causes for a loss of control such as insufficient heat removal and loss of agitation. Overpressurization leading to the bursting of rupture discs takes place several times per year, indicating both the clear need for containment but also a need to consider design and control improvements. The reference describes the autoclave rupture disc assembly, procedures for replacement of the discs, the cleaning of the containment vessels, and the routine maintenance procedures for the containment vessels. 

This is the most convenient method of preparing indole-3-acetic acid if an agitated autoclave is available. The method can be used to prepare other indole-3-acetic acids from a-hydroxy acids. For example, a-methylindole-3-acetic acid has been prepared by condensing indole with lactic acid. 

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