Long-alkyl chain functionalized poly(propylene imine) dendrimer, poly(ethylene imine) hyperbranched polymer, and beta-cyclodextrin derivatives, which are completely insoluble in water, have the property of encapsulating organic pollutants from water. Ceramic porous filters can be impregnated with these compounds resulting in hybrid organic/ inorganic filter modules. These hybrid filter modules were tested for the effective purification of water, by continuous filtration experiments, employing a variety of water pollutants. It has been established that polycyclic aromatic hydrocarbons (PAHs) can be removed very efficiently (more than 95%), and final concentrations of several ppb (microg/ L) are easily obtained. Representatives of the pollutant group of trihalogen methanes (THMs), monoaromatic hydrocarbons (BTX), and pesticides (simazine) can also be removed (>80%), although the filters are saturated considerably faster in these cases.

A series of poly(propylene imine) dendrimers functionalized with long aliphatic chains has been prepared and characterized. The property of these dendrimers to encapsulate polycyclic aromatic hydrocarbons from water down to a few ppb level has been established. The inclusion formation constants are orders of magnitude higher than those reported for activated carbon (from 1.4 × 104 to 3.4 × 105 M-1) or cyclodextrins (10−103 M-1) while they are comparable to those of cyclodextrin polymers (from 1 × 108 to 5 × 109). Furthermore, the loading capacities depend on polycyclic aromatic compounds and the type of alkylated dendrimeric derivatives, that is, 6−19 mg/g for fluoanthrene, 44−67 mg/g for phenanthrene, and 34−57 mg/g for pyrene. Regeneration is also feasible using nonpolar solvents.

Triethoxysilyl-functionalized poly(propylene imine) (DAB32) dendrimer and poly(ethylene imine) (PEI5) hyperbranched polymer were conveniently prepared in chloroform and were subsequently allowed to impregnate porous ceramic filters. Following hydrolysis of triethoxysilyl moieties to Si−OH, polycondensation occurred affording networks containing Si−O−Si bridges with simultaneous formation of Si−O−M bridges resulting from the interaction of Si−OH with M−OH of the ceramic surface. In this manner, covalent binding of the organosilicon dendritic polymers is achieved at the ceramic surface. These porous ceramic filters, impregnated with organosilicon dendritic polymers, were employed for water purification. The concentration of polycyclic aromatic compounds in water was reduced to the level of a few ppb by continuous filtration of contaminated water through these filters. The filters loaded with pollutants were effectively regenerated by treatment with acetonitrile.

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