Abstract In recent years, an increasing attention has been paid to the bioleaching of copper from waste computer motherboards. Here, we investigate the effect of humic acid on the bioleaching of waste computer motherboards using the mixed culture HQ0211. For this, the response surface methodology (RSM) is employed to investigate the effect of pulp density, initial pH and humic acid content on copper recovery. Samples leached at optimized experimental conditions according to RSM were analyzed by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The results show that under optimum conditions; the initial pH = 1.53, pulp density = 1.35% (w/v) and humic acid addition = 0.31 g/L, a complete the copper leaching could be achieved. According to the results, the effectiveness of the bacterial and its capability to oxidize humic acid was proved. Overall, the biological leaching was found to be more effective than the chemical leaching. Humic acid can promote the bioleaching of waste computer motherboards, reducing its environmental hazards.

中文翻译：

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腐植酸在废电脑主板铜生物浸出中的作用

摘要 近年来，废旧电脑主板中铜的生物浸出越来越受到关注。在这里，我们使用混合培养 HQ0211 研究腐殖酸对废电脑主板生物浸出的影响。为此，采用响应面方法 (RSM) 来研究纸浆密度、初始 pH 值和腐殖酸含量对铜回收率的影响。根据 RSM 在优化的实验条件下浸出的样品通过傅里叶变换红外光谱 (FT-IR) 和扫描电子显微镜 (SEM) 和能量色散光谱 (EDS) 进行分析。结果表明，在最佳条件下；初始 pH = 1.53，纸浆密度 = 1.35% (w/v) 和腐植酸添加量 = 0.31 g/L，可以实现完全的铜浸出。根据结果​​，证明了细菌的有效性及其氧化腐殖酸的能力。总的来说，发现生物浸出比化学浸出更有效。腐植酸可以促进废电脑主板的生物浸出，减少其对环境的危害。