Vapor pressure boron trifluoride

Isopropylnaphthalenes can be prepared readily by the catalytic alkylation of naphthalene with propjiene. 2-lsopropylnaphthalene [2027-17-0] is an important intermediate used in the manufacture of 2-naphthol (see Naphthalenederivatives). The alkylation of naphthalene with propjiene, preferably in an inert solvent at 40—100°C with an aluminum chloride, hydrogen fluoride, or boron trifluoride—phosphoric acid catalyst, gives 90—95% wt % 2-isopropylnaphthalene however, a considerable amount of polyalkylate also is produced. Preferably, the propylation of naphthalene is carried out in the vapor phase in a continuous manner, over a phosphoric acid on kieselguhr catalyst under pressure at ca 220—250°C. The alkylate, which is low in di- and polyisopropylnaphthalenes, then is isomerized by recycling over the same catalyst at 240°C or by using aluminum chloride catalyst at 80°C. After distillation, a product containing >90 wt % 2-isopropylnaphthalene is obtained (47). 

The alternate process, the vapor phase method, is carried out at higher pressures (450 psi) and temperatures (750—800°F), and hence, the vapor phase. Producers have been using a boron trifluoride catalyst but any trace water corrodes it unmercifully. Most have now switched to a crystalline aluminosilicate zeolyte catalyst, a more expensive but hardier catalyst. The newer catalyst is also noncorrosive and nonhazardous, cheaper to handle, and produces no waste streams to dispose of... 

Note that ethylbenzene is a derivative of two basic organic chemicals, ethylene and benzene. A vapor-phase method with boron trifluoride, phosphoric acid, or alumina-silica as catalysts has given away to a liquid-phase reaction with aluminum chloride at 90°C and atmospheric pressure. A new Mobil-Badger zeolite catalyst at 420°C and 175-300 psi in the gas phase may be the method of choice for future plants to avoid corrosion problems. The mechanism of the reaction involves complexation of the... 

E. Example Separation of BF3 and CH2CI2. Boron trifluoride (bp —110.7°C) is readily separated from methylene chloride (bp 40.7°C) as illustrated in Fig. 5.6. Inspection of the vapor pressure data in Appendix V reveals that BF3 exerts 75 torr at — 126°C, whereas extrapolation of the vapor pressure data for CH2CI2 to this temperature (log P vs. 1/T plot) indicates a vapor pressure of less than 10 3 torr for this component. Therefore, the reaction mixture is slowly passed through a trap cooled to — 126°C (methylcyclohexane slush bath, see below), which retains the methylene chloride, and into another trap at — 196°C (liquid nitrogen), which retains the boron trifluoride. The rate of trans-... 

The addition takes place according to Markownikoff s rule. The addition of carbo lic acida to the double bonds of isobutylene and trimethyl-ethylene gives tertiary esters. A true equilibrium independent of sulfuric acid concentrations is established in the exothermic reaction. The addition does not go well with ethylene, but goes well with many of the higher alkenes, particularly with some of the terpenes. To avoid the polymerizing effects of sulfuric acid, various other catalysts, such as sulfonic acids, triethylamine, hydrofluoric acid, boron trifluoride, and cuprous chloride have been used. The addition may take place at room temperature or higher and is aided by pressure. The vapors of the acid and hydrocarbon may be passed over catalysts, such as activated carbon, heteropoly acids, or metal phosphates. ... 

TEMPERATURE Degrees Fahrenheit Fig. 1. Vapor Pressure Curve for Boron Trifluoride. 

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