Pentafluoroethane is an important and widely used basic organic chemical intermediate, and its downstream products are used in various fields. This design topic is based on the actual production device of pentafluorochloroethane, referring to the production process and process parameters of the manufacturer of pentafluorochloroethane, adding a hydrodechlorination section, and inferring the feasibility of the design from practical calculation data.The preliminary design of the process for the preparation of pentafluoroethane from the hydrodechlorination of 30,000 tons of pentachlorochloroethane per year is planned to prepare the process design for the future development of the pentafluoroethane process.

2. Design standards

The standards and regulations of this design refer to the relevant information of chemical engineering design, determine the process route, process flow and process parameters of pentafluoroethane synthesis, and process route selection:

（10）The preparation of pentafluoroethane by gas phase catalytic fluorination of C2Cl4, tetrachloroethylene is a common chemical raw material, and the purchase price is low. The process for preparing pentafluoroethane by this method is simple and easy to operate.

（11）The pentafluoroethane hydrogen fluoride addition method to make pentafluoroethane.  This process is a one-step reaction equation in equations. It can easily obtain the target product we need in chemical production, and in the chemical production process, it takes a shorter time, the choice of reactants in the process is a new high, and the product Separation from byproducts is relatively simple.

（12）The pentafluoroethane is produced by the co-production of HFC-125 and HFC-134a.  The reaction is to prepare pentafluoroethane from trichloroethylene, which has the advantages of wide raw materials, easy availability,low production cost, and can simultaneously produce a variety of HFC products, because the increase in the number of manufactured products is difficult to control. Maximize the range of production of our desired products.

（13）Preparation of pentafluoroethane by gas-phase fluorination of HCFC-123.  The process is based on the fact that the process is relatively simple. The disadvantage is that the raw material HCFC-123 is not readily available, resulting in high raw material costs and HCFC-123 is prone to disproportionation during the reaction process. Other fluorines are generated during this reaction process. Chlorocarbon by-products with low product selectivity.

（14）Preparation of pentafluoroethane by gas-phase catalytic fluorination of HCFC-124.  The preparation process is simple, but HCFC-124 is not easy to obtain and the production cost is high. Reactions accompanying the by-product HCl and HCFC-124 will produce HCFC-123, adding new impurities.

（15）Preparation of pentafluoroethane by gas-phase catalytic disproportionation of HCFC-124.  The raw material HCFC-124 is not easy to obtain, and the by-product HFC-123 produced with the reaction also needs to have a good application.

（16）The pentafluoroethane was prepared by HCFC-124 gas-phase catalysis. This process will form an azeotropic mixture with CFC-115 and HFC-125 during the reaction.

（17）Preparation of pentafluoroethane by trifluoromethane cleavage addition method.  The amount of raw materials participating in the reaction is small and single, with fewer by-products generated, and separated by simple distillation and filtration.

（18）Hydrodechlorination of CFC-115.  CFC-115 was hydrodechlorinated on a Pd/C catalyst at a temperature of 350°C.

3. The process is determined

This design is a process for the preparation of pentafluoroethane by hydrodechlorination of 30,000 tons per year of pentafluorochloroethane. After analysis of the final calculation results, this process considers using multiple reactors for simultaneous reaction, so the related process can be pided into 3 Parts of the process operation. For ease of description, the process is pided into various sections for specific instructions.