Dg. Brown et J. Abbot, EFFECTS OF METAL-IONS AND STABILIZERS ON PEROXIDE DECOMPOSITION DURING BLEACHING, Journal of wood chemistry and technology, 15(1), 1995, pp. 85-111
A mathematical model has been formulated to allow the total peroxide c
onsumption during bleaching of a mechanical pulp to be represented by
two separate components; peroxide consumed in reactions with the pulp
and peroxide decomposed in metal catalysed reactions. Using this model
s it is possible to determine the extent of metal catalysed peroxide d
ecomposition in the presence of pulp. This method enables the effects
of transition metal ions and stabilisers during bleaching to be studie
d directly. The use of constant pH conditions facilitates the direct c
omparison of the results obtained during bleaching with those obtained
for analogous systems in the absence of pulp. The presence of pulp ca
n exert a significant influence on the behaviour of transition metal i
ons and stabilisers towards peroxide decomposition. It appears that bo
th the lignin and cellulose components can be responsible for the modi
fications in the catalytic behaviour observed in the presence of pulp.
The effects of stabilisers on the rates of metal catalysed peroxide d
ecomposition during bleaching cannot be predicted by studies conducted
in the absence of pulp.