SU144847A1 - Method for preparing phenyltrichlorosilane - Google Patents

Description

A continuous method for the preparation of phenyltrichlorosnlan by phenyl trichlorosilane benzene is known.

According to this method, the phenylation of trichlorosilane is carried out at a temperature of 450-470 and a pressure of 180 atm with a reaction time of 4 hours in the reaction zone.

At the indicated process indicators, partial pyrolysis of benzene and disproportionation of trichlorosilane occur, which leads to an increase in the specific consumption of raw materials per unit of the desired product and, as a consequence, to an increase in the cost of phenyltrichlorosilane.

The proposed new method for obtaining phenyltrichlorosilane free from the above disadvantages by phenylation of trichlorosilane with benzene is that, in order to simplify the process and improve its quality indicators, metallic aluminum is used as a catalyst.

The catalytic method possesses a variety of advantages over the method currently used.

1. The new method allows to obtain phenyltrichlorosilane in a continuous method at lower temperatures (330-380 ° instead of 450-470 °) and not so high pressure.

2. When the process of phenylation is carried out at these indicators (in the presence of aluminum chips as a catalyst), the productivity of the equipment increases several times. The residence time of the working mixture in the reaction zone by the new method is about one hour (instead of 4 hours or the known method).

3. The phenylchlorosilane condensate obtained by the catalytic process contains a significantly larger percentage of the desired product,

No. 144847-2 -

than with the previously known method, as can be seen from the comparison of the fractional composition of the distillate obtained by catalytic and conventional methods.

All intermediate fractions contain the desired products, which can be isolated during re-distillation.

Example 1. An autoclave with a capacity of 500 ml is loaded with 85 g of be: 150 g of trichlorosilane and aluminum chips as catalysis. Heated at 380–390 ° and pressure 185–190 atm for 1.5 condensate obtained contains 37% phenyltrichlorosilane.

Example 2. In the autoclave of Example 1, benzene and tr1 silane are loaded in a 1: 1 molar ratio and aluminum chips. Nagr 1 hour at 330-340 and pressure 150-160 at. Condensate containing 32.7% phenyltrichlorosilane is obtained.

Example 3. A mixture of trichlorosilane and benzene in a given weight ratio is pumped through a metering pump through a tubular reactor, in which aluminum chips are present as a catalyst. The reactor temperature is maintained at around 380 and the pressure is 120 atm. The duration of stay of the mixture in the reaction zone is 1 hour. The content of phenyltrichlorosilane in the condensate ZB}

Subject invention

The method of producing phenyltrichlorosilane by phenylacetate chlorosilane with benzene, characterized in that, in order to control the process and improve its quality indicators, aluminum metal is used as a mash i.

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