CHEMICALS
Polymers
The removal of gels from a polymer solution is an important filtration application. The optimum filter cartridge for gel removal depends upon the viscosity of the solution, the operating differential pressure and the gel concentration. Dr. A. Keith Fritzche of Parker Hannifin in an article in Filtration News recommends resin bonded cartridges for high viscosity solutions operating at high differential pressure as well as containing moderate to high gel concentrations. Melt blown cartridges may be used for lower viscosity solutions with moderate to high gel concentrations and operating at low to moderate differential pressures. For those solutions of low viscosity and very low gel concentrations pleated filtration cartridges may be used.
Cartridges are used in the removal of gels and black specks in polyethylene, polypropylene and fluorinated polymers.
Mott porous metal systems have been used in this application for over 40 years. Because the units are all metal they withstand high temperatures and pressures and resist corrosion. Strictly controlled porosity prevents catalyst loss. Ceramic filters are also used for catalyst recovery.