A Combined Theoretical and Experimental Framework for Shifting to Greener Reagents in Mineral Processing

选矿过程中使用了许多有毒或有害的试剂，这些试剂在尾矿库中处置后，会对工作场所的健康造成不利影响，并污染环境。废水和卫生法规的逐步收紧预示着，未来该行业将被迫用更绿色的替代品取代有毒试剂，以保持其社会许可证。为了满足这一需求，开发更绿色的可再生表面活性剂替代品(例如浮选中的捕收剂和调节剂)是很重要的。*目前开发新的浮选表面活性剂的策略是反复试验，这是昂贵和困难的，而预测工具箱由软硬酸碱规则、静电相互作用的pH控制和表面识别等通用规则组成。然而，即使在一般水平上，可再生表面活性剂的预测规则也没有出现，这些可再生表面活性剂不同于传统的表面活性剂，因为它们的头基较大，具有多个吸附部分和结构异构体。另一种计算方法，如密度泛函理论(DFT)，也具有很大的挑战性，因为它在捕捉矿物-溶液界面和模拟真实矿物颗粒不同结构和组成缺陷的计算成本方面存在局限性，这需要为大量可再生表面活性剂的头基筛选数千个吸附结构，这是不切实际的。*为了加速将可再生表面活性剂引入浮选实践，我提议开发和测试一种基于描述符的方法，允许预测矿物表面对可再生表面活性剂的亲和力。利用吸附能之间的标度关系，进一步降低了计算成本。2007年引入的比例关系是发展催化剂计算设计的决定性一步。然而，这种先进的方法还没有被用于浮选药剂的筛选。理论预测将使用光谱、界面和浮选技术进一步验证和修正。*主要实践成果是a)矿业采用更清洁的矿石加工技术，对环境影响更小，b)在石油和天然气回收等其他行业使用可再生表面活性剂的指导方针。拟议的跨学科研究将培训下一代高素质的人员，掌握先进的研究和工程方法，不仅在矿产行业，而且在石油和天然气、化工、油漆和颜料以及消费者护理行业，都需要促进可持续发展。

Mineral processing utilizes many toxic or hazardous reagents which have adverse health effects in the workplace and pollute the environment after disposal in tailing ponds. The progressive tightening of wastewater and health regulations portends a future where the industry, to preserve its social license, will be forced to replace the toxic reagents by the greener alternatives. To meet this need, it is important to develop greener renewable alternatives to the conventional surfactants (e.g. collectors and regulators in flotation).***The current strategy for the development of new flotation surfactants is trial and error, which is costly and arduous, while the prediction toolbox consists of generic rules such as the soft hard acid base rule, pH control of the electrostatic interactions, and surface recognition. However, even at a generic level, predictive rules have not emerged for renewable surfactants which differ from the conventional counterparts by bulkier headgroups with multiple adsorption moieties and structural isomers. An alternative computational approach, such as density functional theory (DFT), is also very challenging given its limitations to capture the mineral-solution interface and computational cost to model different structural and compositional defects of real-world mineral particles, which entails impractical screening of thousand adsorption structures for a large set of headgroups of renewable surfactants.***To accelerate the introduction of renewable surfactants to flotation practices, I propose to develop and test a descriptor-based approach that allows predicting the affinity of mineral surfaces to the renewable surfactants. The computational cost will further be reduced by employing scaling relations between the adsorption energies of adsorbates. The introduction of scaling relations in 2007 was a decisive step in evolving the computational design of catalysts. However, this advanced approach has not been used for screening flotation reagents as yet. The theoretical predictions will further be tested and corrected using spectroscopic, interfacial, and flotation techniques.***The major practical outcomes are a) cleaner ore processing technologies for mineral industry with less impact on the environment, b) guidelines for employing renewable surfactants in other industries such as oil and gas recovery. The proposed interdisciplinary research will train the next generation of highly qualified personnel in the advanced research and engineering approaches required to advance sustainability not only in mineral industries but also in oil and gas, chemical, paints and pigments, and consumer care industries.**