Novel Understanding of Simultaneous Extraction of Vanadium and Manganese from Vanadium Slag and Low-Grade Pyrolusite Based on Selective Oxidation–Reduction Roasting

Abstract

Fresh thinking based on selective oxidation− reduction roasting was proposed to recover vanadium and manganese from vanadium slag (VS) and low-grade pyrolusite (LGP) simultaneously. This approach is inspired by the fact that vanadium (V 3+ ) in VS needs to be oxidized, while manganese (Mn 4+ ) in LGP needs to be reduced. X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) were performed to analyze the selective oxidation−reduction mechanism of VS and LGP (VS&LGP). During the roasting process, V 3+ in VS and Mn 4+ in LGP were initially oxidized and reduced to form Fe 0.07 V 1.93 O 4 (V 4+ ) and Mn 2 O 3 (Mn 3+ ) until it reached a temperature of 670 °C. After reaching 670 °C, Mn 3+ in LGP gradually oxidized V 4+ and further separated vanadium from iron to form acid-soluble manganese vanadate, by which Mn 3+ was reduced further as Mn 2+ . The extraction rates of vanadium and manganese from VS&LGP, roasted at 1000 °C and leached with acid, achieved 86.24 and 93.86%, respectively. V 2 O 5 and chemical MnO 2 with purities of 99.23 and 91.98% were generated after vanadium and manganese precipitation. Tailings with high iron content and low sulfur content could be returned to blast furnaces for ironmaking. This new method in which VS and LGP were used as additives to each other achieved the efficient and simultaneous recovery of vanadium and manganese.

Promoting the Calcified Roasting of Vanadium Slag Based on the CeO2-Catalytic Oxidation Mechanism

“…Vanadium in vanadium slag reacts with calcification additives to form acid-soluble calcium vanadate to improve the leaching rate of vanadium. 6,12 In recent years, research related to strengthening roasting has been reported, such as the proposed BaCO 3 /CaO composite roasting, 13 MgO/CaO composite roasting, 9 manganese roasting, 14 microwave roasting, 15 and so forth. It is mostly understood and emphasizes the role of roasting vanadium slag from the destruction of the spinel phase structure.…”

Element Migration Behaviors During the Reduction of Vanadium Slag for Iron‐Removal and Vanadium‐Enrichment

“…[11] Herein, it is meaningful to explore a short, low production cost and environment-friendly technology for the production of FeV alloy, and producing FeV alloy using VS directly has been caused much attention. [12][13][14] In the past decades, based on the fact that the spinel phase is wrapped by silicate phase in VS, [15,16] a two-step direct reduction to produce FeV alloy using VS was investigated by many researchers to solve the environmental pollution problem of leaching liquor wastewater and further shorten the production routing. [17,18] The first step reduction, namely, prereduction, was the enrichment of vanadium by selective carbothermic or silicothermic reduction of FeO x and other impurities except for V 2 O 3 , satisfying the composition goal of the production of FeV60 alloy (50-65 wt% V).…”

Extraction of Vanadium from New Zealand Titanomagnetite Sand and Vanadium Recovery Concentrate

“…Many studies have reported either the coextraction, or the solid-state combination of vanadium and manganese in metallurgical contexts. [38][39][40] For this reason, and for reasons which pertain to the results of this thesis, a brief overview of the Mn-V literature is warranted. While not many studies have been conducted into Mn-V systems, there are two categories which is considered: Mn-V alloys, and Mn-V oxides.…”