Artificial Neural Network Aided Design Of Catalyst For Hexafluoropropene Hydrofluorination

Because of the destruction to the ozone layer in the atmosphere, the production of chlorofluorocarbons (CFCs) and Halons have stopped and their usages are cutting down in the developed countries , but also in the developing countries their productivity is under reduction . Therefore ,as the substitute of CFC and Halon , hydrofluorocarbons (HFCs) become more and more important in the social and industrial fields . 1,1,1,2,3,3,3,-Heptafluoropropane (F-227) is one of the substitute showing a very good prospect in the future . Generally , the synthesis of HFCs is more difficult than that of CFCs and Halons . The key point is how to introduce the hydrogen atom into the molecule . A catalyst with superior performance will be the foundation to resolve this question.Both the catalysts used in hydrofluorination and fluorination in gas-solid phase reaction system have many common characters . The compounds containing aluminum , chromium and active carbon are generally used as the catalyst . Some metallic elements , such as aluminum, chromium, iron, nickel , copper , silver , manganese , magnesium , cobalt , rhodium , zinc , cadmium , vanadium , molybdenum , titanium and so on are used as the catalytic active components. The catalysts are usually prepared by impregnation , precipitation , co-mixing , and thermal decomposition methods. The impregnation method is the most common and important one in all methods for this purpose . The carrier of the catalyst is mostly aluminum oxyfluoride, chromium oxyfluoride or active carbon.Many factors have to be considered in catalyst design , such as the selection of catalytic active component, prepara-...