The gas phase slow combustion of propionaldehyde

✍ Scribed by G. Skirrow; B.P. Whim

• Publisher: Elsevier Science
• Year: 1968
• Tongue: English
• Weight: 701 KB
• Volume: 12
• Category: Article
• ISSN: 0010-2180
• DOI: 10.1016/0010-2180(68)90024-2

✦ Synopsis

An investigation has been made of the gas phase slow combustion of propionaldehyde between 1550 and 220°C. The process is autocatalytic, and at 155°C the reaction proceeded with a pressure decrease throughout most of its course, perpropionic acid (the branching intermediate) being the major product over the first half of the reaction. With increase of temperature the reaction ~became more complex becau~ of the instability of the peracid, and the pressure/time curve showed a minimum. Considerable amounts of secondary products including acetaldehyde and ethylene were formed at 220°C. At constant temperature (220°C) the maximum rate of pressure decrease was proportional to the rate of oxygen uptake, but the proportionality constant was temperature dependent, and overall activation energies estimated from the rate of oxygen consumption were higher than those estimated from the rate of pressure decrease.

At high oxygen concentrations the rate was independent of oxygen pressure but proportional to the square of the aldehyde pressure. The rate became increasingly dependent on the oxygen pressure and less dependent on the aldehyde pressure as the pressure of the oxygen decreased. The overall activation energy was higher for oxygen-rich mixtures. A possible reaction scheme to account for the oxygen dependent rate is discusse4.