Use of nanoparticular and soluble anionic celluloses in coagulation-flocculation treatment of kaolin suspension

Henrikki Liimatainen*, Juho Sirvio, Ola Sundman, Osmo Hormi, Jouko Niinimaki

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

49 Citations (Scopus)


In this work, the effectiveness of a novel, combined coagulation-flocculation treatment based on alum and soluble or nanoparticular anionic derivatives of dialdehyde cellulose, ADAC, was evaluated by studying the removal of colloidal material in a model suspension containing kaolin. Four different ADACs with varying degrees of substitution, size and water solubility were synthesized by periodate oxidation and sulfonation of cellulose. The effects of ADAC dosage, solution pH and temperature on flocculation were studied by measuring residual turbidity of the settled suspension. Moreover, the charge densities, sizes, zeta-potentials and stability of the ADACs in aqueous solutions were studied. The combined treatment was effective in the removal of colloidal particles, as demonstrated by reduced residual turbidity with remarkably lower total chemical consumption compared with coagulation with alum alone. Of the ADACs, samples with lower solubility that contained cellulose nanoparticles performed better than the fully water-soluble sample. Due to the restricted pH tolerance of alum, the combined treatment was effective only at acidic conditions (pH <5), although the ADACs were found to be stable in a much broader pH range (pH of 3 to about 9). ADACs also retained strong activity at higher temperatures (30-60 degrees C) and after several days of storage in aqueous solution. (C) 2012 Elsevier Ltd. All rights reserved.

Original languageEnglish
Pages (from-to)2159-2166
Number of pages8
JournalWater Research
Issue number7
Publication statusPublished - 1 May 2012
MoE publication typeA1 Journal article-refereed


  • Anionic cellulose
  • Dialdehyde cellulose
  • Flocculant
  • Kaolin clay
  • Nanoparticles

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