Adsorption of Trisiloxane Surfactant for Selective Flotation of Scheelite from Calcite at Room Temperature

Abstract

The separation and enrichment of scheelite from calcite are hindered by the similar active Ca2+ sites of scheelite and the calcite with calciferous gangue. Herein, a novel trisiloxane surfactant, N-(2-aminoethyl)-3-aminopropyltrisiloxane (AATS), was first explored and synthesized and recommended as the collector for the flotation separation of scheelite from calcite. The micro-flotation and mixed binary mineral flotation tests showed that AATS had excellent collection performance for scheelite and high selectivity for calcite within a wide pH range. At the same time, contact angle and zeta-potential measurements, Fourier transform infrared (FTIR) analysis, and density functional theory (DFT) calculations revealed the relevant adsorption mechanism. The contact angle measurement showed that AATS can increase the contact angle of the scheelite surface from 41.7 to 95.8°, greatly enhancing the hydrophobicity of the mineral surface. The results of FTIR analysis and zeta-potential measurement explained that AATS was electrostatically adsorbed on the mineral surface, and DFT calculation further verified that the −N+H3-positive group in AATS was adsorbed on the negatively charged scheelite surface. Therefore, AATS can realize the expectation of high efficiency and selectivity of minerals and enhance the adhesion between the surface of scheelite minerals and bubbles, providing a fresh approach to industrial production.

Research Progress with Scheelite Flotation Reagents: A Review

“…The authors studied the mechanism for adsorption of AATS on the mineral surface. The cationic collector mainly interacted with the negatively charged scheelite surface through electrostatic interactions and showed less adsorption on the positively charged calcite surface, which provided the selective separation of scheelite and calcite [83]. This collector also exhibited good separation performance in the flotation of wolframite and calcite [84].…”

“…In single-mineral flotation experiments, the flotation recovery rate for scheelite reached 96%, while that for calcite was only 5.5%. In binary mixed mineral experiments using AATS for flotation of a mixed mineral with a WO 3 grade of 38.65%, the concentrate grade and recovery of WO 3 were significantly higher than those of sodium oleate flotation; they reached 64.63% and 87.47%, respectively, compared to 35.20% and 79.34% for sodium oleate [83]. The authors studied the mechanism for adsorption of AATS on the mineral surface.…”

A silanized magnetic amino-functionalized carbon nanotube-based multi-ion imprinted polymer for the selective aqueous decontamination of heavy metal ions

“…3a) shows the typical absorption bands related to the C-H (474-707 cm À1 ), C-O (1105 cm À1 ), C-N (1370 cm À1 ), CQC (1549 cm À1 ), CQO (1670 cm À1 ), N-H (2885 cm À1 ), C-H (2924 cm À1 ), and O-H (3425 cm À1 ) stretching vibrations. 32,33 The NH 2 -CNTs/Fe 3 O 4 (Fig. 3b) spectrum shows an additional absorption peak due to the Fe-O stretching vibration (485 cm À1 ) along with the NH 2 -CNT-related bands, which overlapped with the peak of the C-H bond.…”

Removal of Ciprofloxacin from Water by a Potassium Carbonate-Activated Sycamore Floc-Based Carbonaceous Adsorbent: Adsorption Behavior and Mechanism

“…The methods to remove CIP from water mainly contain photodegradation, catalytic oxidation, membrane separation and adsorption . As a result of the characteristics of simple operation, high performance, and low cost, adsorption is one of the most common and effective technical means. − Thus, an appropriate adsorbent is crucial in adsorption. In general, materials with large porosity and a large specific surface area have a higher adsorption capacity .…”