Advanced simulation to choose a cheaper membrane process for salt removal from complex mixtures Original Research Article

Most of chemical reactions have — as a final result — a large mixture of end products out of which the main one represents a small rate when compared with secondary products. One of these reactions results in a mixture of products that takes place in the process obtaining ethylene amines. The reaction occurring at elevated pressure and temperature, between dichloroethane and ammonia, conducts to amino-chlorohydrates intermediate products which are then neutralized by means of NaOH. Finally the amines and NaCl are formed. Then excess ammonia is removed resulting in a mixture of NaCl, water and amines. Currently a procedure separated the amines from the rest of the components by evaporation and centrifugation. Since this desalting method causes many problems regarding steam consumption, clogging, corrosion and erosion of the equipment, it was suggested in a previous paper, based on pilot scale calculations (100 l/h), to solve these problems by using membrane technology, i.e. ED or PV. The study pointed out that PV appeared to be more advantageous than ED. The new paper takes into account the same membrane processes as the previous study using advanced simulation for the variables involved in the process, including the sensitivity cost analysis as well. The scale of the current plant is an industrial one (5400–7200 kg/h) and therefore the results can be a more realistic support for a potential investor.