新型白钨矿分离羟肟酸捕收剂的分子设计

Molecular design of a new hydroxamic acid collector for scheelite flotation separation

采用密度泛函理论模拟计算白钨矿(001)和萤石(111)解理面的结构特征及空间质点分布,并通过对羟肟酸与矿物表面吸附构型的分析,指出羟肟酸中非极性基对极性基官能团结构的影响会继而影响羟肟酸对白钨矿和萤石的选择性。论文基于该思路设计并合成一种新型的6-邻环己烷二甲酰亚胺基己基羟肟酸捕收剂(DIHHA)。通过核磁共振、元素分析以及红外光谱对合成产品进行表征,并对环己烷羟肟酸(CHA)进行了捕收剂的纯矿物浮选实验以及人工混合矿浮选实验。结果表明:DIHHA显示出比CHA更佳的选择性,是一种极具前景的白钨矿-萤石分离捕收剂。该实验结果与理论计算推测结果非常吻合,证明采用密度泛函理论模拟计算矿物晶体表面及捕收剂分子空间结构,并结合吸附构型分析,能够为捕收剂分子设计提供有效指导。

According to the structure characteristics and spatial distribution of scheelite(001) and fluorite(111) cleavage surfaces calculated by the density functional theory, together with the analysis of adsorption model of hydroxamic acid with crystal surfaces, the selectivity of hydroxamic acid collector for scheelite flotation separation was thought to be affected by the structure of the polar group, which was affected by the non-polar groups. Based on this idea, a new type of(6-(1,3-dioxooctahydro-2 H-isoindol-2-yl)-N-hydroxyhexanamide)(DIHHA) collector was designed and synthesized. The synthetic products were characterized by NMR, elemental analysis and infrared spectroscopy. The scheelite and fluorite pure mineral flotation and artificial mixed minerals flotation experiments of DIHHA were studied by compared with cyclohexane hydroxamic acid(CHA). The results show that DIHHA has better selectivity than CHA and is a promising new collector for flotation separation of scheelite and fluorite. The experimental results are in good agreement with the theoretical calculations, which indicates that the simulation calculation of mineral crystal surface and collector molecular structure by density functional theory, combined with the adsorption configuration analysis, can provide effective guidance for the design of collector molecules.