Tessenderlo Kerley, Inc.

Tessenderio Kerley, Inc.

Alexandros Dimitriadis

Michael Massoud Hojjatie

Constance Lynn Frank Lockhart

Jeroen Van Cauwenbergh

Mark P Clarkson

Harry Charles Kominski

Adam T Goldsmith

Nicholas S Shult

Constance Lynn Lockhart

Roeland Van Dael

Theodore E Cook

A method of depressing copper sulfides and iron sulfides in a molybdenite flotation recovery process that uses alkaline or alkaline earth polysulfides. The method of enriching molybdenite content from a slurry having molybdenite and at least one of iron sulfides and copper sulfides can include the steps of adding an effective amount of a depressing reagent selected from one or more alkaline polysulfides, alkaline earth polysulfides, or a mixture thereof, to the slurry, wherein the pH of the slurry is greater than about; and passing a gas through the slurry to separate material by selective flotation, and recovering the molybdenite from a froth.

Depression of copper and iron sulfides in molybdenite flotation circuits

The invention relates to a process for preparing potassium thiosulfate, potassium sulfite or potassium bisulfite comprising the following steps:

Sulfur dioxide scrubbing system and process for producing potassium products

An efficient process for preparation of potassium thiosulfate (KSO) is described. Potassium hydroxide (KOH) and elemental sulfur (S) are converted to potassium polysulfide, which is subsequently oxidized. The process allows using specifically designed process conditions such as mole ratios of potassium hydroxide to sulfur, and temperature, to obtain an optimized formulation of desired polysulfide, and a specifically designed set of conditions such as temperature, pressure, rate and duration of the oxidant during the oxidation conditions, to obtain a relatively high concentration of soluble potassium thiosulfate product with high purity, with relatively low amounts of byproducts. The manufacturing process can either be a batch process or a continuous process utilizing Continuous Stirred Tank Reactors (CSTR). The CSTR process is dependent on several design parameters, including pressure, and temperature optimization to avoid product instability. The resulting potassium thiosulfate is a beneficial fertilizer with high potassium content as a 50% liquid source of potassium.

Oxidation process for producing potassium thiosulfate

An efficient process for the continuous preparation of calcium thiosulfate (CaSO) from lime sulfur, through oxidation is described. The process involves oxidizing calcium polysulfide intermediate in a series of reactors to produce calcium thiosulfate as a clear liquid in high concentration with minimal byproducts. The process results in the complete destruction of polythionates, permitting the calcium thiosulfate produced to be useful in certain leaching processes for precious metals. The invention further makes it possible to recycle the process water from the leaching process for use as a raw material reactant in the process for calcium thiosulfate production.

Continuous process for preparation of calcium thiosulfate liquid solution

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Chandler, AZ, United States of America

Alexandros Dimitriadis