Rt. Echols et Jf. Tyson, DETERMINATION OF RATE CONSTANTS BY A DOUBLE-LINE FLOW-INJECTION METHOD INCORPORATING A WELL-STIRRED TANK REACTOR, Talanta, 41(10), 1994, pp. 1775-1784
Equations have been derived for the concentration-time profiles of rea
ctants and products in a first order reaction obtained on passage of a
reactant plug through a single well-stirred tank reactor. When taken
together with the equations for physical dispersion of such a reactor
under plug flow conditions, an expression for the reaction rate consta
nt was derived which allowed its experimental determination in a relat
ively simple fashion. The method was tested for reactions between ceri
um and oxalic acid and between dichromate and ascorbic acid, for which
values of the rate constants of around 2 x 10(2) sec(-1) and 5.5 x 10
(3) sec(-1) were obtained. Good agreement with other experimentally de
termined values was obtained. The scope and the limitations of the pro
posed method are critically discussed with the aid of some model calcu
lations. The range of Values for which the method might be suitable is
approximately 10(-3)-10(-1) sec(-1). An equation analogous to a peak-
width equation was derived as a further development of this approach.
Good agreement with the previously determined values were obtained for
both systems. The extension of the method to reactions other than fir
st order is discussed.