Process for preparing vermiculite permselective membranes
Abstract
Abstract A PERMSELECTIVE MEMBRANE IS PREPARED BY PROVIDING AN AQUEOUS SUSPENSION OF SODIUM EXFOLIATED VERMICULITE, REPLACING AT LEAST PART OF THE ECCHANGER SITES WITH IONS OF A METAL OF GROUPS I-A AND II-A OF THE PERIODIC TABLE, FLOCCULATING THE RESULTING SUSPENSION, AND DEWATERING THE FLOCCULATED MASS WHEREBY THE VERMICULITE PLATELETS ARE ALIGNED INTO A THIN COHESIVE MEMBRANE. THE MEMBRANE IS USEFUL IN A VARIETY OF SELECTIVE SEPARATION PROCESSES, SUCH AS WATER PURIFICATION, AND TO PROCESS OTHER SOLVENTS HAVING SOLUBLE IONIC CONTAMINANTS. THE MEMBRANE MAY BE FURTHER MODIFIED TO PROVIDE DESICCATING PROPERITIES BY INCORPORATING VARIOUS SOLID ADSORBENTS, SUCN AS SILICA GEL AND ACTIVATED CARBON.
Inventors
- 👤 A Patil
- 👤 R Rice
- 👤 J Kraus
Bibliographic Details
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