Trace amounts of toxic metals are usually difficult to be purified by conventional chemical precipitation or physical adsorption in wastewater. In this study, in order to realize high-value utilization of coal fly ash for wastewater purification, a novel method was applied to prepare high-performance mesoporous silica materials from coal fly ash. In comparison with a commonly used method, characterizations revealed that the new method obtained mesoporous silica nanospheres with uniformly distributed cyano groups (denoted by MSN), while the common method only obtained irregular sponge-like microstructure (denoted by ISM). Besides, MSN showed better hydrothermal stability, higher specific surface area (693 m²/g) and more ordered mesopores from the comparison. Moreover, the sorption experiments of simulated wastewater suggested that MSN was better in removing toxic metals (Ni²⁺ and Cd²⁺) than ISM. For the practical wastewater from a battery plant, 2 g/L dosage of MSN showed excellent performance for purification of trace amounts of various toxic metals (Ni, Cd, Mn, Zn, Hg and Pb), the concentration of which reduced to ppb level after MSN treated. The results suggested that MSN can be an effective and low-cost sorbent for removing various toxic metals from wastewater.

中文翻译：

---

用粉煤灰新颖合成氰基官能化介孔二氧化硅纳米球（MSN），用于去除废水中的有毒金属

通常很难通过常规的化学沉淀或废水中的物理吸附来纯化痕量有毒金属。为了实现粉煤灰在废水净化中的高价值利用，采用了一种新的方法从粉煤灰制备高性能介孔二氧化硅材料。与常用方法相比，表征表明，该新方法获得了具有均匀分布的氰基的介孔二氧化硅纳米球（以MSN表示），而普通方法仅获得了不规则的海绵状微结构（以ISM表示）。此外，MSN表现出更好的水热稳定性，更高的比表面积（693 m ²/ g），并从比较中得出更多有序的中孔。此外，模拟废水的吸附实验表明，MSN在去除有毒金属（Ni ²⁺和Cd ²⁺）方面比ISM更好。对于电池厂的实际废水，以2 g / L的剂量添加MSN表现出优异的净化痕量各种有毒金属（Ni，Cd，Mn，Zn，Hg和Pb）的性能，其浓度降至ppb水平经过MSN处理。结果表明，MSN可以作为一种有效且低成本的吸附剂，用于去除废水中的各种有毒金属。