Novel catalysis mechanisms of benzohydroxamic acid adsorption by lead ions and changes in the surface of scheelite particles

Selective Separation of Scheelite from Calcite by Self-Assembly of H2SiO3 Polymer Using Al3+ in Pb-BHA Flotation

“…The Pb-BHA complex is a metal-organic collector, where the metal is the functional group that recognizes the W-O bonds on the scheelite surface. This approach is significantly different from traditional anion collectors that react with Ca sites on the mineral surface [17]. The adsorption diagram of silicic acid and Pb-BHA on the scheelite or calcite surface is shown in Figure 10.…”

“…The selective adsorption of sodium silicate on minerals is significantly improved by modification with polyvalent metal ions, such as Fe(II), Pb(II), Cu(II), Mg(II), and Al(III) [10,12,[14][15][16], especially for application in scheelite flotation. The Pb-benzohydroxamic acid (BHA) complex, a novel metal-organic collector, has shown specificity toward scheelite, contributing to the flotation separation of scheelite from other calcium minerals [4,17,18]. A simplified flotation process using Pb-BHA complexes was developed to replace the energy-inefficient Petrov's process involving the use of a fatty acid to increase the recovery of scheelite and reduce the overall cost.…”

Novel Insights into the Configurations of Lead(II)-Benzohydroxamic Acid Coordination Compounds in Aqueous: A Combined Experimental and Computational Study

“…Recently, their promising applications in mining have attracted research attention [1][2][3][4][5][6][7][8]. For instance, lead(II)-benzohydroxamic acid (Pb [II]-BHA) complexes are effective collectors in the beneficiation of oxide minerals, including tungsten minerals, cassiterite, and rutile [9,10]. Given the excellent selectivity and good collecting ability of Pb(II)-BHA, the scheelite flotation process could be simplified remarkably without the addition of sodium silicate, overcoming the shortage of heating in the routine flotation of scheelite [9][10][11].The beneficiation of scheelite is currently one of the most challenging problems worldwide in the field of mineral processing.…”

“…For instance, lead(II)-benzohydroxamic acid (Pb [II]-BHA) complexes are effective collectors in the beneficiation of oxide minerals, including tungsten minerals, cassiterite, and rutile [9,10]. Given the excellent selectivity and good collecting ability of Pb(II)-BHA, the scheelite flotation process could be simplified remarkably without the addition of sodium silicate, overcoming the shortage of heating in the routine flotation of scheelite [9][10][11].The beneficiation of scheelite is currently one of the most challenging problems worldwide in the field of mineral processing. Conventionally, separating scheelite from calcium bearing minerals, such as fluorite and calcite, by using anionic collectors (especially for fatty acid) is difficult due to their highly similar properties in calcium-bearing surfaces.…”

“…Conventionally, separating scheelite from calcium bearing minerals, such as fluorite and calcite, by using anionic collectors (especially for fatty acid) is difficult due to their highly similar properties in calcium-bearing surfaces. Fortunately, our group first introduced the Pb complexes of benzohydroxamic acid (Pb(II)-BHA complexes) to effectively separate scheelite from calcium-bearing gangues by properly regulating the Pb/BHA ratio and pH [9,11]. Furthermore, as displayed in Figure 1(b), the novel flotation scheme (i in Figure 1 [a]), with Pb(II)-BHA complexes used as the collector, has shown better performance than the traditional activation flotation scheme (ii in Figure 1 [a]), which first added Pb(II) as the activator and subsequently added BHA as the collector [10,[12][13][14][15][16][17][18][19][20].…”