Abstract: A process for the production of hydrogen bromide gas by direct combustion of bromine in hydrogen involves carrying out the combustion reaction in an apparatus chamber made of impregnated graphite and a cooling zone composed of a steel jacket in which are piled blocks of impregnated graphite.

Abstract: Ethylene is chlorinated in a reaction zone to form a product stream containing 1,2-dichloroethane, the latter being then thermally cracked in a cracking zone to form vinyl chloride. Light by-products formed during the thermal cracking step are chlorinated in a zone external and directly downstream of the reaction zone used for the preparation of the 1,2-dichloroethane product stream. The product stream leaving the chlorination reaction zone for the 1,2-dichloroethane are passed into said downstream zone so that the light by-products are chlorinated in the presence of said product stream.

Abstract: A process for the production of hydrogen bromide gas by direct combustion of bromine in hydrogen involves carrying out the combustion reaction in an apparatus chamber made of impregnated graphite and a cooling zone composed of a steel jacket in which are piled blocks of impregnated graphite.

Abstract: The flow rate of a high temperature fluid flowing through a conduit is measured by passing ultrasonic waves through the fluid. The ultrasonic waves are emitted from an emitter located at one side of the conduit and are received by a receiver located at an opposite site thereof. A first spacer is disposed between the receiver and the conduit, and a second spacer is disposed between the emitter and the conduit. The spacers isolate the receiver and emitter from the high temperatures and conduct the ultrasonic waves without changing the frequency thereof. A quick-release clamp clamps the emitter, receiver and spacers together against the conduit.