kLadetermination: comparative study for a gas mass balance method

The determination ofkLaby a gas balance method coupled with sulphite oxidation is compared for three kinds of processes (stirred tank, bubble column and fixed-bed column reactors) with a gassing-in and with a classical chemical sulphite oxidation method. The mathematical relations required for the determination of thekLavalue are detailed. In coalescing gas–liquid conditions, the values calculated by the three methods are shown to be comparable. The gas balance method is more rapid than either the steady-state gassing-in or the chemical sulphite reaction rate measurement methods. It is also well adapted for three-phase systems (gas–liquid–solid) in which the non-coalescing effects of sulphite solution are reduced by solid interferences.The determination ofkLaby a gas balance method coupled with sulphite oxidation is compared for three kinds of processes (stirred tank, bubble column and fixed-bed column reactors) with a gassing-in and with a classical chemical sulphite oxidation method. The mathematical relations required for the determination of thekLavalue are detailed. In coalescing gas–liquid conditions, the values calculated by the three methods are shown to be comparable. The gas balance method is more rapid than either the steady-state gassing-in or the chemical sulphite reaction rate measurement methods. It is also well adapted for three-phase systems (gas–liquid–solid) in which the non-coalescing effects of sulphite solution are reduced by solid interferences.