Minerals Engineering, Vol. 6, No. 2, pp. 231-234, 1993 0892-6875/93 $5.00+0.00 Printed in Great Britain Pergamon Press Ltd

NEW PATENTS

This section contains abstracts and, where appropriate, illustrations of recently issued United States patents and published patent application filed from over 30 countries under the Patent Cooperation Treaty. This information was obtained from recent additions to the PATSEARCH ® online database in accordance with interest profiles developed by the Editors.

Further information about online patent searching can be obtained from Research on Demand, Inc., 2421 Fourth Street, Ste. C., Berkeley, CA 94710, U.S.A. [Tel. 510-841 1145; Fax 510-841 6311].

5104445

P R O C E S S F O R R E C O V E R I N G M E T A L S F R O M R E F R A C T O R Y

O R E S

Michael Dubrovsky, Paul J Marcantonio as- signed to Chevron Research & Technology Co

The present invention is a process to recover metals from refractory ores. It involves the chlorination of an ore concentrate in the pre- sence of solid salt at a temperature between 300 degrees and 650 degrees C. Thereafter, an oxida- tion step can be used to convert iron chloride to iron oxide. Subsequent separation steps remove the salt, gangue, and iron oxides. Separate path- ways are described for precious and base metal recovery.

5108584

A P P A R A T U S F O R E X T R A T I N G H E A V Y M E T A L S F R O M O R E

Raymon Brosseuk, Surrey, Canada

A machine is employed for recovering heavy metals, such as gold, from placer ore. The machine employs a cylindrical, annular outer drum mounted for rotation at an inclination to the horizontal and including at least one spiral vane extending the length of its inner surface. A cylindrical, annular inner barrel is mounted within the drum and has an upper fragmentation section, an intermediate trommel section, and a lower discharge section. A spray of water is directed into the inner barrel and a water spray bar is located in the annulus between the inner barrel and the outer drum. A sluice box is located

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to receive an input discharge from the upper end of the outer drum. The ore is separated into large tailings that are discharged from the lower end of the inner barrel and fine, light tailings from the outer drum. The heaviest and finest portions of the material are carried by a spiral on the inner surface of the outer drum and discharged into the upper end of the sluice box from the upper end of the outer drum. The sluice box includes a plurality of landings upon which heavy materials, such as gold, collect. The outer drum is subjected to vibration to aid in the recovery process.

5108585

F L O T A T I O N O F N O N - S U L F I D I C O R E W I T H A G L Y C O S I D I C

C O L L E C T O R

Wolfgang von Rybinski, Rita Koester, Manfred Biermann, Harald Schnegelberger, Duesseldorf, Federal Republic Of Germany assigned to Henkel Kommanditgesellschaft auf Aktien

A collecting agent and method for the recovery of valuable minerals in the froth flotation beneficiation of non-sulfidic ores is provided. The collecting agent is selected from alkyl glycosides, alkenyl glycosides and mixtures thereof. Preferably, the collecting agent is a com- bination of an alkyl glycoside, an alkenyl glycoside and mixtures thereof with a non-thio ionizable surfactant collector. Glycosides con- taining from about 2 to 8 glycoside residues may be used. The alkyl and alkenyl components of these glycosides may be linear or branched, may contain from about 2 to 18 carbon atoms and may optionally contain a hydroxyl group or an ether linkage.