Apparatus for the chemical synthesis of an evaporant and a liquid has a cryogenic pumping device between the evaporant source and the reaction region and a pump causes the liquid to be continuously recirculated until the reaction is completed, the pressure in the evaporation region being maintained substantially...http://www.google.fr/patents/US4182749?utm_source=gb-gplus-shareBrevet US4182749 - Chemical synthesis apparatus and method
