L. Rihko, J. Linnekoski, A. Krause
Oct 1, 1994
Citations
1
Influential Citations
51
Citations
Journal
Journal of Chemical & Engineering Data
Abstract
Tertiary ethers are used as octane-enhancing components in gasoline. Equilibrium constants for the liquid-phase synthesis of 2-methoxy-2-methylbutane (TAME) and 2-ethoxy-20methylbutane (TAEE) were measured in the temperature range 323-363 K. The equilibria were studied using the alcohol/alkene mixture in various mole ratios and the respective ether as a reagent in a batch reactor. A commercial cation exchange resin (Amberlyst 16) was used as the catalyst. The system was strongly nonideal, and the UNIQUAC estimation method was used in the calculation of the liquid-phase activity coefficients. The experimental equilibrium constants are given as a function of temperature. At 333 K the equilibrium constants K[sub a] for the synthesis of TAME were 39.6 [+-] 2.5 from methanol and 2-methyl-1-butene (2M1B) and 4.1 [+-] 0.3 from 2-methyl-2-butene (2M2B). The equilibrium constants for the synthesis of TAEE were 17.4 [+-] 1.1 from ethanol and 2M1B and 1.7 [+-] 0.1 from 2M2B. The experimental [Delta][sub r]H values for the liquid-phase synthesis of TAME were [minus]33.6[+-]5.1 kJ/mol (2M1B) and [minus]26.8 [+-] 2.3 kJ/mol (2M2B), and those for the synthesis of TAEE were [minus]35.2 [+-] 5.8 kJ/mol (2M1B) and [minus]27.3 [+-] 6.7 kJ/mol (2M2B). The results were compared with the literature values.