Adsorption of model wood polymers and colloids on bentonites

The adsorption of model water-soluble wood polymers and colloids on bentonites was investigated. Polymers form molecular monolayers on the montmorillonite surface while colloids adsorb as particles. All components follow a low-affinity Langmuir isotherm. The observed maximal adsorbed quantities suggest that the montmorillonite particles are fully de-layered after swelling in water. The results are analysed in the context of papermaking, where bentonites are used as adsorbents for process contaminants.