Symmetrical quaternary ammonium compounds and their use in heavy metals recovery
Patent 4289530 Issued on September 15, 1981. Estimated Expiration Date: 
January 18, 2000. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
January 18, 2000. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2221163 2580473 3539605 3785803 3790370 3859210 3873581 Recovery of silver from silver-containing solutions Solvent extraction of metals from acidic solutions with quaternary ammonium salts of hydrogen ion exchange agents Process for the removal of metals from solution Patent #: 4167481 InventorAssigneeApplicationNo. 06/113279 filed on 01/18/1980US Classes:75/417, Obtaining metal from photographic waste210/688, Heavy metal423/24, Ion exchanging or liquid-liquid extracting423/25, Sorbing or magnetic separating423/48, Forming sulfide or matte564/282, Benzene ring containing75/416, Combined with step at less than 300 degrees C using nonmetallic material which is liquid under standard conditions (e.g., hydrometallurgy, etc.)75/713, From photography material75/722Involving organic compound containing metal or organic agent for agglomerating metalExaminersPrimary: Ozaki, G.International ClassesC02F 1/28 (20060101)G03C 5/395 (20060101) C22B 3/28 (20060101) C22B 3/00 (20060101) AbstractSymmetrical quaternary ammonium compounds of the formula ##STR1## are disclosed, wherein each Ar is identical and is phenyl or a condensed polynuclear aryl group having 2 to 4 aryl nuclei, each R is identical and is alkyl of 1 to 4 carbon atoms, X⦵ is a salt-forming anion of valence 1 or 2 and n is 1 or 2 depending on the choice of X. Also disclosed are apparatus and processes for the recovery of heavy metals such as silver, gold and other precious metals from solution in water. The disclosed quaternary ammonium compounds are adsorbed to a suitable substrate, preferably alumina, and the treatment water is passed therethrough. A second bed of divided metal such as aluminum is disclosed for use in series with the bed incorporating the quaternary ammonium compounds.Other References
|
| ||||||||||||||
