Aggregation and sedimentation stability of microcrystalline cellulose suspensions in aqueous aluminum nitrate solutions

The aggregation and sedimentation stability of dilute suspensions of microcrystalline cellulose in aqueous solutions of Al(NO₃)₃(2 × 10⁻⁵–2 × 10⁻³ mol/l) is studied by the photometric method at pH 2–11. It is found that, in the absence of Al(NO₃)₃, microcrystalline cellulose suspensions are stable with respect to aggregation throughout the pH range in question. The addition of Al(NO₃)₃ induces the coagulation and accelerates the sedimentation of microcrystalline cellulose aggregates. At all concentrations of Al(NO₃)₃, the maximum loss in stability is observed at pH 7–9. Original Russian Text ? P.M. Mosur, A.V. Lorentsson, Yu.M. Chernoberezhskii, 2009, published in Kolloidnyi Zhurnal, 2009, Vol. 71, No. 4, pp. 566–568.