Increased solubility of quartz in water due to complexing by organic compounds
Increased solubility of quartz in water due to complexing by organic compounds
复制标题
由于有机化合物络合，石英在水中的溶解度增加
作者：
Philip C. Bennett;Donald I. Siegel
石英是最稳定的天然固相二氧化硅。它在地球表面的风化极其缓慢，即使在所有其他硅酸盐矿物都已降解之后，它仍能抵抗风化作用。然而，来自古代和现代环境的充分证据表明，在石英溶解度的无机控制不能轻易解释的条件下，二氧化硅的溶解和流动性增强了。石英的溶解度增加已被观察到，特别是在富含有机物质的土壤中；然而，溶解有机碳和溶解二氧化硅之间没有直接联系。在这里，我们提出了石英在天然水中溶解度增加的证据，这是由溶解的有机化合物引起的。这些化合物是由石油的生物降解产生的，主要由有机酸的复杂混合物组成。我们认为二氧化硅在接近中性pH值的水中被这些有机酸络合和动员。
Quartz is the most stable natural solid phase of silica. It weathers extremely slowly at the Earth's surface1, and often resists weathering even after all other silicate minerals have been degraded. However, there is ample evidence from both ancient and modern environments indicating enhanced dissolution and mobility of silica under conditions that cannot easily be explained by the inorganic controls of quartz solubility2. Increased solubility of quartz has been observed particularly in soils rich in organic material; however, no direct link between dissolved organic carbon and dissolved silica has been identified3. Here we present evidence for an increase in the solubility of quartz in a natural water brought about by dissolved organic compounds. These compounds were produced by the biodegradation of petroleum, and consist largely of a complex mixture of organic acids. We propose that silica is being complexed and mobilized by these organic acids in waters having close to neutral pH.