Following solvent extraction, reduction and precipitation are conducted on an industrial scale and typically involve oxalic acid and/or sodium oxalate [22,23], SO2 gas [25], metabisulfite [29], or sodium sulfite [25]. Sodium sulfite reduction presents several drawbacks, including high energy consumption (operating at 75 °C), significant SO2 emissions, environmental pollution, and the generation of sodium sulfate and sodium chloride, which can affect gold powder quality. In contrast, oxalic acid is favored for its rapid reduction, good selectivity, and ability to produce gold powder with a purity exceeding 99.99%, surpassing that of SO2 [13].
For industrial silver leaching, sodium s
Strategic Non-Closure in the War on Iran
by Amin Nouri
The unprecedented expenditure of Tomahawk missiles in the war imposed on Iran reveals more than the scale of coalition firepower. It exposes the structural limits of a magazine-intensive precision campaign confronting a defender built for survivability, underground depth, retaliatory persistence, and theater-wide coercion. The central issue is no longer access, which the coalition secured early, but closure, which it has yet to impose on Iran’s surviving missile and maritime architecture.
