Condensor temperature

A 41 resin reactor, equipped with a condensor, a stirrer and a nitrogen inlet, is charged with a polyether polyol and maleic anhydride. The mixture is heated to 60 °C and the catalyst is added. The mixture is then heated to 185 °C for 10 h or until the acid number is reduced to 140mgKOH/g. Some propylene glycol is added and the mixture is maintained at this temperature for another 4h or until the acid number is lowered to about 40mgKOH/g. The yield is about 90 %. 

In a 100 ml flask fitted with a mechanical stirrer, a vertical condensor protected by a calcium chloride stopper, a dropping-funnel and a source of nitrogen were introduced 30 ml of hexamethylenephosphotriamide and 2.3 g (0.1 mol) of finely cut sodium wire. A mixture of 12.3 g (0.1 mol) of (3-thienyl)-acetonitrile and 16.3 g (0.1 mol) of cyclohexyl bromide was then quickly added at a temperature of 20 C. The reaction mixture was then maintained under nitrogen atmosphere and stirred for 12 hours at room temperature. The excess of sodium was destroyed by adding 5 ml of ethanol and the organic solution was slowly poured into 100 ml of a 1 N iced solution of hydrochloric acid. The solution was extracted twice with 100 ml ether. The ethereal phases were collected, washed with water, dried and concentrated under reduced pressure. The crude product was then purified by... 

Fig. 3 Schematic diagram of the gas-handling system and the environment-controlled AFM chamber. The alcohol partial pressure is controlled by varying the ratio of dry Ar and alcohol saturated Ar gas flowrates. The alcohol saturated Ar gas stream is generated by flowing Ar through a heated bubbler followed by a condensor held at room temperature.

In a three-necked flask equipped with reflux-condensor and magnetic stirrer, the olefin 2,3-dimethyl-2-butene 1 (3.24 g 38.5 mmol), solvent (20 mL), H2O2 (30 wt% aqueous 1.8 g 15.88 mmol) and an exact amount of internal standard 1,3,5-tri-rerf-butylbenzene were mixed and, under stirring, the solution was warmed to the required reaction temperature (Table 3). The catalyst (50 mg) was added at once (t = 0) and the reaction mixture was stirred vigorously during the whole reaction time. The formation of 3 was followed by taking samples of the reaction mixture followed by GC analysis. 

To keep the reactor gas phase above the U.F.L. in chlorine (method 2) may not be quite safe. On start-up the temperature must be set to the process normal value ensuring enough fuel vapour pressure before chlorine injection. If a condensor is used where the fuel vapour pressure is depleted, the gas flow composition may enter the flammable range. Glass condensors are better not used or protected from light. 

Refrigerated Vapor Condensor. This removes VOCs from a gas stream by condensation at very low temperatures, typically around -112°F (-80°C). As an example, refrigerated condensation is used to remove gasoline from air displaced by fuel transfer operations. It is most apphcable to gas streams with flow rates less than 1000 standard cubic feet per minute (scfm) and VOC concentrations of at least several hundred ppm. 

The static value of the pressure response is determined by the so-called self-regulation in the reboiler and condensor (see Fig. 34.3) a higher pressure results in higher top and bottom temperatures, which result in improved heat transfer in the condensor and decreased heat transfer in the reboiler. Eventually, the equilibrium between Vc and will be restored. 

Used as PTC thermistor, excess current protection element low-temperature heat, temperature sensor, condensor. 

A two necked 100 ml reaction vessel with reflux condensor, magnetic stirring bar and thermometer was charged with 25 ml toluene and 0.001 mol (0.32 g) tetrabutylammonium bromide (3) (Fluka >98%). The solution was stirred at ambient temperature until all crystals had dissolved. Then 0.02 mol (3.2 g, 2.5 ml) of distilled bis-(2-chloroethyl) sulfide (1) was added and the solution was stirred again. Finally 25 ml of 8 N aqueous sodium hydroxide (0.2 mol) and 8 g of NaOH (Merck, 99%) in 25 ml water were placed in the vessel. The mixture was stirred (600 rpm) and heated to 60 C using a heating jacket. 

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