Contemplated is a sensor system for use with a measuring device. The measuring device being of the type adapted to measure the volume of a desired solid component in a sample volume of a solid-liquid slurry obtained from either a carbon-in-pulp or carbon-in-leach process. The solid-liquid slurry comprises granular carbon particles, ore pulp, and water. The carbon-in-pulp or carbon-in-leach process includes at least one retention tank. The measurement device including: a receptacle for receiving the sample volume of the slurry; a screen provided in the receptacle for separating out the desired solid component from a remainder of the slurry. The solid component is retained in the receptacle to form a bed therein and the remainder is exhausted from the receptacle. The sensor system measures in either the retained solid component, or the exhausted remainder, or both one of: pH; dissolved oxygen; pulp density or carbon content.

Desirable methods for larger scale silver nanoplate synthesis are described along with methods for applying a noble metal coating onto the silver nanoplates to form coated silver nanoplates with a desirable absorption spectrum. The silver nanoplates are suitable for use in coatings for altering the hue of a transparent film. The hue adjustment can be particularly desirable for transparent conductive films.

Any metal having a low α-ray emission, the metal being any one of tin, silver, copper, zinc, or indium, wherein an emission of an α-ray after heating the metal at 100° C. in an atmosphere for six hours is 0.002 cph/cm.sup.2 or less. Any metal of tin, silver, copper, zinc and indium each including lead as an impurity is dissolved to prepare a hydrosulfate aqueous solution of the metal and lead sulfate is precipitated and removed in the solution. The lead sulfate is precipitated in the hydrosulfate aqueous solution by adding a lead nitrate aqueous solution including lead having an α-ray emission of 10 cph/cm.sup.2 or less to the hydrosulfate aqueous solution, from which the lead sulfate has been removed, and, at the same time, the solution is circulated while removing the lead sulfate to electrowinning the metal using the hydrosulfate aqueous solution as an electrolytic solution.

Provided is a platinum-group metal recovery method for efficiently recovering a platinum-group metal. The method for recovering a platinum-group metal includes an immobilization step of causing a molten product of a raw material containing a platinum-group metal, a molten product of a carbonate or hydroxide of an alkali metal, a molten product of an oxide, and a ceramic material to make contact with each other so as to immobilize the platinum-group metal on the ceramic material.

Alkaline oxidation process for treating refractory sulfide ore or concentrate particles enriched in a metal to be recovered comprising stages in which refractory ore or concentrate particles are surface-oxidized in an alkaline oxidation step in alkaline liquid phase with calcium hydroxide forming an alkaline slurry, which slurry is thereafter mechanically activated to remove passivating coatings from the surface oxidized refractory ore particles.

A precious metal leaching method includes providing a slurried feed, comprising (i) in the solid phase, a refractory sulfide-containing material, the material comprising at least about 0.05 oz/tonne of a precious metal, at least about 0.75 wt. % sulfides, optionally at least about 0.1 wt. % feldspar (i.e., muscovite), and at least 0.3 wt. % preg-robbing carbonaceous material; and oxidizing the sulfide-containing material at more than about 240° C. and super-atmospheric pressure to oxidize at least most of the carbonaceous material and optionally convert at least most of the sulfide sulfur to sulfate sulfur and form an oxidized precious metal-containing material, wherein at least one of the following is performed during oxidizing: maintaining a pH of at least about pH 1.5; maintaining at least about 98.5% of the feldspar (i.e., muscovite) in the solid phase; maintaining a dissolved cupric ion concentration of at least about 0.25 g/L; and maintaining the slurried feed under subcritical or supercritical water operating conditions.

The invention relates to a process for recovering metals from aqueous solutions or solid feedstocks such as ores and waste. In particular, the invention relates to a method of recovering a target metal using a microorganism and recycling depleted growth media or depleted lixiviant back through the process.

The disclosure provides a magnetic reagent comprised of a recombinant yeast cell having the following genetic modifications: impairment of the CCC1 gene; addition of at least one copy of a human ferritin gene complex; addition of at least one copy of a TCO89 gene; and addition of at least one copy of a mineral- or metal ion-adsorbing target peptide, wherein the magnetic susceptibility or mass magnetization of said magnetic reagent is greater than it would be for a native yeast.

A process for roasting of metal concentrate wherein concentrate particles are fed into a roaster where they are thermally treated at a temperature in the range of 500 and 1200° C. in a fluidized bed to form a calcine. At least parts of the calcine are withdrawn from the roaster together with a gas stream as a solid fraction. Concentrate particles with a diameter at least 50% smaller than the average diameter of the concentrate particles are separated as small particles and/or particles from the gas-solid-fraction are separated in at least one step as small calcine particles and/or particles are gained in another hydrometallurgical step as other particles. Defined particles are pelletized, whereby at least 80% of the pellets feature a diameter of at least 80% of the concentrate particles average diameter. The pellets are fed into the roaster.

A process for treating minerals containing metal sulphide and a precious metal, the process comprising fine grinding the minerals and subjecting the minerals to a first leaching step conducted under oxidising conditions at a pH of from 5 to 7, and subjecting a pulp or suspension or solid residue from the first leaching step to a second leaching step conducted under oxidising conditions at a pH of at least 9.0.