New Patents 1205

4968415

PROCESS FOR SELECTIVE FLOTATION OF PHOSPHORUS

MINERALS

Hans-Joachi Morawietz, Werner Ritschel, Kurt Bauer, Kelkheim, Federal Republic Of Germany assigned to Hoechst Aktiengesellschaft

A process for selective flotation of phosphate minerals, wherein a compound of the formula la or 1 b See Patent for Chemical Structure in which R1 is branched or unbranched C8-C24-alkenyl, R2 is branched or unbranched C1-C4-alkyl and M is hydrogen, ammonium, triethanolam- monium, an alkali metal atom or an alkaline earth metal atom, is added as a collecting agent to the flotation suspension.

4968416

1,4-DISUBSTITUTED-2 3,5,6- TETRAHYDROXY-1 4-

DIPHOSPHORINANES AND THEIR OXIDES OR SULFIDES

AND THEIR USE IN FROTH FLOTATION

Allan J Robertson, James B Gallivan assigned to American Cyanamid Company

Various 1,4-disubstituted-2 3,5,6-tetrahydroxy- 1 4-diphosphorinanes, their oxides and sulfides, methods for the production thereof, flame- retarded compositions of matter containing them and froth flotation processes therewith, are disclosed.

4971625

METHOD FOR LEACHING GOLD AND[OR SILVER OUT OF ORES

OR OUT OF ORE- CONCENTRATES AND ALSO OUT

OF PRECIOUS-METAL WASTES OR PRECIOUS-METAL SCRAP BY

USING CYANIDE-CONTAINING LEACHING SOLUTIONS

Albert Bahr, Clausthal Zellerfeld, Federal Republic Of Germany assigned to Degussa Ak- tiengesellschaft

A method for leaching gold and/or silver out or other precious metal containing substance using

cyanide-containing leaching solutions and adding an aqueous H202 solution to accelerate leaching. The total amount of the hydrogen- peroxide solution required for leaching is fed into the leaching slurry at the beginning of leaching. The amount of the H202 solution is determined in that the H202 is added in a 0.6 to 2.5-fold stoichiometric ratio to the cyanide con- centration of the leaching slurry. The pH value of the leaching slurry is set and maintained at between 7 and 10 or between 11 and 13.

4971656

FLOTATION PROCESS FOR DEINKING PRINTED WASTE

PAPER

Klaus Lehmann, Andrea Domsch, Hans Hawel, Gregor Schuster, Illertissen, Federal Republic Of Germany assigned to Chemische Fabrik Gruenau GmbH

A flotation process for the de-inking of printed waste-paper by treating the paper pulp in the pulper at alkaline pH-values by means of alkali silicate, oxidative bleaches and separating the loosened printing-ink particles from the fibrous material suspension by flotation, in which pro- tein fatty acid condensates are added finely dist- ributed, possibly together with dispersing agents, in a solution or dispersion which is fluid at normal temperature.

4971685

BUBBLE INJECTED HYDROCYCLONE FLOTATION

CELL

Donald Stanley, Cy E Jordan assigned to The United States of America as represented by the Secretary of the Interior

A method and apparatus for selectively separating a mixture of hydrophobic and hydro- philic mineral particles. A mineral pulp is pre- pared which includes minerals ground to a predetermined size. A bubble slurry is then pre- pared which includes a gas entrained in a liquid to form bubbles of a predetermined size. The mineral pulp and bubble slurry are simul- taneously injected into the cell apparatus. The cell has an enclosed body with a feed receiving portion, a narrowed apex portion with an under- flow discharge, and an intermediately disposed merger zone. A mineral pulp feed port extends

1206 New Patents

into and is directed tangentially to the feed receiving portion in the mineral pulp feed zone. The bubble slurry feed port, disposed in the same direction as the mineral pulp feed port, extends into and is directed tangentially to the feed receiving portion in the bubble slurry zone. A vortex finder, having a tubular member which has one end extending exterior of the feed receiving portion and another end extending into the merger zone, is attached to and extends axially of the feed receiving portion. The mineral pulp and the bubble slurry merge in the merger zone, hydrophobic particles form a froth and exit through the vortex finder, and the hydro- philic particles exit through the underflow dis- charge, thereby separating the mixture mineral particles.

4971731

METHOD AND APPARATUS FOR GENERATING MICROBUBBLES

IN FROTH FLOTATION MINERAL CONCENTRATION SYSTEMS

A method and apparatus for generating micro- bubbles in a flowing liquid stream for use in a froth flotation system. The system utilizes a microbubble generator having a tubular housing with an inlet end and an outlet end. Located coaxially within the housing is an inner member with an elongated, tapered, exterior surface. A porous tubular sleeve is mounted between the housing and the inner member coaxially there- with to define with the cylindrical interior sur- face of the housing an elongated air chamber of annular cross section. The porous sleeve has a cylindrical inner surface that defines with the ex- terior surface of the inner member an elongated liquid flow chamber of thin, annular cross sec- tion. An aqueous liquid is supplied to the liquid flow chamber at a relatively high flow rate and air under pressure is supplied to the air chamber so that air is forced radially inwardly through the porous sleeve to be diffused in the form of micro- bubbles in the flowing stream.

Donald E Zipperian assigned to Deister Con- centrator Company Inc

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