electrolyte
A liquid, paste, or solid that lets electric charge travel through a battery or other device — like a highway for tiny charged particles moving between the two ends of a battery.
Технически: In electrochemical systems, an electrolyte is the medium that conducts ionic current between electrodes while remaining electrically insulating with respect to electron flow, thereby forcing electrons to pass through the external circuit. It may be a liquid solution of dissolved salts or acids, a polymer gel, a molten salt, or a solid ceramic, depending on the application and operating temperature. The electrolyte is often confused with the electrode: the distinction is that electrodes are the sites of oxidation and reduction reactions, whereas the electrolyte merely facilitates ion transport between them without itself being consumed in the principal cell reaction under normal operating conditions.
Materials
electrorefining
A way of purifying metal using electricity. An impure block of metal slowly dissolves in a liquid, and the pure metal re-forms on a clean sheet nearby, leaving the impurities behind.
Технически: Electrorefining passes a direct current through an electrolyte solution between an impure metal anode and a pure metal starting cathode, causing the anode to dissolve and the target metal to deposit selectively onto the cathode at a purity that can exceed the anode grade. Base metals more noble than copper remain undissolved, while less noble metals dissolve but do not deposit under the controlled voltage conditions, accumulating instead in solution or in the anode slime. The process is distinct from electrowinning, in which metal is deposited from a leach solution rather than from a dissolving metal anode.
Processing
enrichment
A process that increases the proportion of one particular variety of an element relative to the others — in uranium, that means increasing the share of the type of atom that can sustain a nuclear reaction.
Технически: Enrichment, in the context of nuclear materials, is the process of increasing the concentration of fissile uranium-235 relative to the more abundant uranium-238, most commonly by gaseous diffusion or gas centrifuge acting on uranium hexafluoride. Natural uranium contains a low proportion of U-235; most reactor designs require a higher proportion, and weapons-grade material requires a much higher proportion still. The term should not be confused with beneficiation or upgrading of metallic ores, where 'enrichment' is sometimes used loosely to mean increasing the grade of a concentrate; in nuclear fuel-cycle reporting, enrichment has a precise quantitative meaning expressed as assay in weight percent U-235.
Processing
evaporite
An evaporite is a rock made from minerals that were left behind when a body of salty water dried up, the way a ring of white salt forms around the edge of a puddle as it evaporates.
Технически: An evaporite is a sedimentary rock composed predominantly of minerals precipitated by the progressive concentration and eventual evaporation of saline water, either in marine basins or continental lake settings; common evaporite minerals include halite, gypsum, anhydrite, sylvite, and various borates and lithium salts. The sequence in which minerals precipitate follows solubility order, so the stratigraphic position within an evaporite succession indicates the degree of concentration the original brine reached and the depositional environment. Evaporites are economically significant both as ore themselves — potash and lithium brine deposits are evaporitic — and as host rocks or seals for other commodities, and their physical properties, particularly plasticity and low density, have important consequences for the structural geology of any basin in which they occur.
Geology
export control
A rule that says a country must give permission before certain materials or products can be sent abroad, like a gate that only opens with the right key.
Технически: A government-imposed restriction on the export of specified goods, technologies or materials, typically administered through licensing requirements. In minerals supply chains, export controls are applied to raw ores, concentrates or refined products that a producing country wishes to retain for domestic processing or to limit access by foreign parties. They are distinct from export taxes, which permit trade but impose a cost, whereas export controls can prohibit trade outright or subject it to case-by-case approval.
Markets