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
Liquidity Wars and the New Politics of Supply Chains
by Amin Nouri
Digital platforms that finance invoices and pay suppliers early are quietly becoming one of the strongest levers in the global economy. As great powers harden rival blocs and the South struggles with debt and exclusion, control over these trade finance rails will shape who can industrialize, who gets cut off in a crisis, and how far sanctions, climate rules, and industrial policy can reach beyond national borders.