| 摘要 |
A composite biosorption material is formed of a hydrophilic urethane binder containing immobilized bioactive organisms of at least about one micron in size and having active sites for binding and removing noxious materials such as metal ions from an effluent such as a waste water stream. To form the composite, a prepolymer is prepared by heating polyethylene glycol, having an average molecular weight of about 1000, to over 200 DEG F. up to 350 DEG F., preferably greater than 220 DEG F., and reacting a diisocyanate with the heated polyethylene glycol while mixing to form the prepolymer. After cooling, the prepolymer is mixed with an aqueous slurry containing the organisms such as Datura innoxia cells, and optionally a surfactant and bactericide, in a weight ratio such as 1:1 to 6:1, and the resultant mixture is cured to form the composite material containing a dry weight of the organisms such as about 15% to 90%. The diisocyanate may be a mixture of toluene diisocyanate 2-4 and toluene diisocyanate 2-6, and at a ratio of diisocyanate to polyethylene glycol to stoichiometrically end cap the polyethylene glycol with a content of isocyanate groups of between 2% and 14%.
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