A less harmful approach for the environment regarding chalcopyrite concentrate leaching, using seawater/brine and caliche’s salts as a source of chloride and nitrate ions, was investigated. Different variables were evaluated: sulfuric acid concentration, sodium nitrate concentration, chloride concentration, source of water (distilled water, seawater, and brine), temperature, concentrate sample type, nitrate source (analytical grade and industrial salt), and pre-treatment methods in order to obtain maximum copper extraction. All tests were performed at moderate temperatures (≤45 °C) and atmospheric pressure. The leaching system using distilled water, seawater, and brine base media resulted in copper extraction of 70.9%, 90.6%, and 86.6% respectively. The leaching media, with a concentration of 20 g/L Cl⁻, obtained a maximum Cu extraction of 93.5%. An increase in the concentration of H₂SO₄ and NaNO₃ from 0.5 to 0.7 M, led to an increase in the copper extraction. The use of an industrial salt compared to the analytical salt did not show great variations in the percentage of extraction achieved, which would be a good and cost effective alternative. The increase in temperature from 25 to 45 °C showed a great effect on the copper leaching (of 60% until 90.6%, respectively). The pre-treatment is suggested to increase copper extraction from 60.0% to 71.4%.

中文翻译：

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海水/盐水和Caliche盐作为清洁和环保的氯离子和硝酸根离子来源，用于黄铜矿精矿浸出

研究了使用海水/盐水和加利奇盐作为氯离子和硝酸根离子源的黄铜矿精矿浸出对环境的危害较小的方法。评估了不同的变量：硫酸浓度，硝酸钠浓度，氯化物浓度，水源（蒸馏水，海水和盐水），温度，精矿样品类型，硝酸盐源（分析级和工业盐）以及预处理方法为了获得最大的铜提取量。所有测试均在中等温度（≤45°C）和大气压下进行。使用蒸馏水，海水和盐水作为基本介质的浸出系统分别提取了70.9％，90.6％和86.6％的铜。浸出媒体，有20g / L的浓度氯^-，获得的最大铜提取率为93.5％。H ₂ SO ₄和NaNO ₃的浓度从0.5增加到0.7 M，导致铜提取量增加。与分析盐相比，使用工业盐不会显示出所获得的萃取百分比有很大变化，这将是一种很好且具有成本效益的选择。温度从25升高到45°C对铜的浸出有很大影响（分别为60％至90.6％）。建议进行预处理，以将铜提取率从60.0％提高到71.4％。