摘要 |
<p>Tubular filter elements, comprising a metallic or ceramic support on which are porous mineral layers with smaller pores than those of the support, are prepd. by contacting a wall of the support with a suspension of a mineral in a liq., and draining, drying, compressing and heating the support. The suspension may contain an organic substance to modify the rheological properties and ensure mechanical strength. The mineral is e.g. a metal oxide or fluoride.Process is simpler than existing ones and the appts. is less complex and more suitable for making a large sequence of elemements.</p> |