Methanol, production Linde

Materiala. Nonionic surfactants Brij 52 (B52) and Brij 30 (B30) were obtained from the Sigma Chemical Company and used as received. These surfactants are ethoxylated alcohols with the nominal structures Cie a and C12E4, respectively, where E represents the number of ethylene oxide units. Acrylamide was obtained from the Aldrich Chemical Company (Gold Label 99-1-%) and recrystallized twice from chloroform. Azo bis(isobutyrnitrile) (AIBN), obtained from the Alfa Products Division of Morton Thiokol, was recrystallized from methanol. Water was doubly deionized. Propane obtained from Union Carbide Linde Division (CP Grade) and ethane from Air Products (CP Grade) were used without further purification. 

In the partial oxidation for the production of methanol (POX/methanol) complex, a major portion of the visbreaker residue (approximately 670,000 tons per annum) is converted to gas. Part of the syngas produced in the POX is used to cover the hydrogen demand of the refinery. Therefore, a plant producing high purity hydrogen has been installed and is operated by Linde. Another part of the syngas is added to the refinery fuel gas system for consumption in the process furnaces, which are exclusively gas fired. 

The pore size of a molecular sieve can be modified by exchange of the cations incorporated into the aluminosilicate skeleton. In general, molecular sieves of small pore size (ca. 4 A 0.4 nm) are the most suitable for dehydration (e.g., the Linde 0.4 nm product of Union Carbide, or products equivalent to this). In addition to water molecules, this molecular sieve is suitable for the binding of carbon dioxide, hydrogen sulphide, sulphur dioxide, ammonia, methanol and other molecules of similar size. For chemical reasons, however, its affinity for water is so much higher than that for the other molecules of similar size that it may even be used for the dehydration of methanol. As an example of the effectiveness of this sieve, it can reduce the water content of ethanol from 0.5% to 10 ppm. 

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