The chemical equilibrium of the reaction of acetic acid etherification with butanol in a combined reaction-rectifying apparatus is studied; a mathematical model that describes the chemical equilibrium in the conditions selected is proposed.

Possible process flow sheets for the separation of a quaternary mixture formed in the production of methyl tert-butyl ether were synthesized using different special methods, and the most energy-efficient flow sheet was selected.

The phase equilibrium in an acetonitrile + water + cyclohexene + chloroform system was studied at 101.3 kPa. A prediction regarding the internal structure of the composition tetrahedron (presence/absence of one/two internal singular points) was made using thermodynamic modeling in AspenPlus V.10.0. The existence of two internal quaternary azeotropes (of node type with a minimum boiling point and of saddle type) was confirmed as a result of a full-scale experiment. Thermodynamic-topological analysis of the structure of phase equilibrium diagrams was carried out to confirm the correctness of the diagram construction.