The mathematical model of pyrolysis process (ethane+BBF) taking into account feedback has been developed. On the basis of the model there has been carried out the optimization of unrecirculating process, as a result of which the scheme of control of the pyrolysis process of (ethane+BBF) depending on totality of the controlled parameters has been composed. Three variants of carrying out the pyrolysis process of (ethane+BBF) with recirculation at various compositions and quantities of recirculant have been considered. The advantages of the process realization with recirculation in comparison with unrecirculating process have been shown.