School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi 710055, China.
Water Res. 2012 Sep 1;46(13):4063-70. doi: 10.1016/j.watres.2012.05.017. Epub 2012 May 18.
Manganese (II) is commonly present in drinking water. This paper mainly focuses on the adsorption of manganese on suspended and deposited amorphous Al(OH)(3) solids. The effects of water flow rate and water quality parameters, including solution pH and the concentrations of Mn(2+), humic acid, and co-existing cations on adsorption were investigated. It was found that chemical adsorption mainly took place in drinking water with pHs above 7.5; suspended Al(OH)(3) showed strong adsorption capacity for Mn(2+). When the total Mn(2+) input was 3 mg/L, 1.0 g solid could accumulate approximately 24.0 mg of Mn(2+) at 15 °C. In drinking water with pHs below 7.5, because of H(+) inhibition, active reaction sites on amorphous Al(OH)(3) surface were much less. The adsorption of Mn(2+) on Al(OH)(3) changed gradually from chemical coordination to physical adsorption. In drinking water with high concentrations of Ca(2+), Mg(2+), Fe(3+), and HA, the removal of Mn(2+) was enhanced due to the effects of co-precipitation and adsorption. In solution with 1.0 mg/L HA, the residual concentration of Mn(2+) was below 0.005 mg/L, much lower than the limit value required by the Chinese Standard for Drinking Water Quality. Unlike suspended Al(OH)(3), deposited Al(OH)(3) had a much lower adsorption capacity of 0.85 mg/g, and the variation in flow rate and major water quality parameters had little effect on it. Improved managements of water age, pipe flushing and mechanical cleaning were suggested to control residual Mn(2+).
锰（II）通常存在于饮用水中。本文主要研究了悬浮和沉积无定形 Al(OH)(3)固体对锰的吸附。考察了水流速度和水质参数（包括溶液 pH 值以及 Mn(2+)、腐殖酸和共存阳离子的浓度）对吸附的影响。结果表明，化学吸附主要发生在 pH 值高于 7.5 的饮用水中；悬浮 Al(OH)(3)对 Mn(2+)具有很强的吸附能力。当总 Mn(2+)输入量为 3mg/L 时，在 15°C 下，1.0g 固体可累积约 24.0mg 的 Mn(2+)。在 pH 值低于 7.5 的饮用水中，由于 H(+)的抑制作用，无定形 Al(OH)(3)表面的活性反应位点要少得多。Mn(2+)在 Al(OH)(3)上的吸附逐渐从化学配位转变为物理吸附。在 Ca(2+)、Mg(2+)、Fe(3+)和 HA 浓度较高的饮用水中，由于共沉淀和吸附的影响，Mn(2+)的去除率得到提高。在 1.0mg/L HA 的溶液中，Mn(2+)的残留浓度低于 0.005mg/L，远低于中国《生活饮用水卫生标准》的限值。与悬浮 Al(OH)(3)不同，沉积 Al(OH)(3)的吸附容量要低得多，为 0.85mg/g，流速和主要水质参数的变化对其影响很小。建议加强对水龄、管道冲洗和机械清洗的管理，以控制残留的 Mn(2+)。
