Chromatographic Procedure for the Determination of Products of the Direct Synthesis of Dimethyl Ether

Abstract

We developed an original gas chromatographic procedure for determining the products and reagents for the catalytic synthesis of dimethyl ether (DME) from synthesis gas, which enables the simultaneous detection of СН₃ОН, DME, СО, СО₂, Н₂, Н₂О, N₂, and hydrocarbons to С₆. The gas circuit includes four detectors, three packed columns, two precolumns (to prevent water and organic compounds from entering molecular sieve columns) in combination with two relief valves and two pressure regulators for the implementation of the back purging of precolumns. The system is assembled based on a Khromatek-Kristall 5000 chromatograph. The determination is carried out at a constant temperature of 140°C. The duration of analysis is not more than 12 min. Because of the presence of a flame ionization detector, it is possible to detect trace amounts of hydrocarbons, as well as ethane in the presence of large amounts of CO₂.