A Sustainable Technique to Prepare High-Purity Vanadium Pentoxide via Purification with Low Ammonium Consumption

Abstract

The general preparation method for V2O5 is ammonium salt vanadium precipitation, which inevitably produces large amounts of ammonia nitrogen wastewater. In this paper, we propose an environmentally friendly method for preparing high-purity V2O5 with low ammonium consumption. The purity of the V2O5 product reaches more than 99% while reducing the level of ammonium consumption. The vanadium precipitation efficiency reaches 99.23% and the V2O5 purity of the product reaches 99.05% under the following conditions: precipitation time of 1.5 h, precipitation temperature of 98 °C, initial precipitation pH of 2, ammonium addition coefficient of 2, purification time of 5 min with purification performed twice, purification temperature of 65 °C. In this study, compared with the use of ammonia spirit for vanadium precipitation and ammonium salt vanadium precipitation, the ammonia consumption levels are reduced by 79.80% and 80.00%, and the purity levels are increased by 0.70% and 1.01%, respectively. The compositions of the precipitated (NaV3O8∙xH2O) and purified ((NH4)2V6O16·1.5H2O) hydrolysis products are characterized via XRD. The TGA results show that NaV3O8∙xH2O contains 1.5 times the amount of crystal water. The FTIR results explain that the two V3O8− layers are combined end-to-end to form a V6O162− layer. The change of the product image indicates that the purification process includes three stages. Firstly, heating and NH4+ attack expand the V3O8− layer. NH4+ diffuses more easily into the V3O8− layer. Secondly, NH4+ destroys the electrostatic interaction between Na+ with the V3O8− layer and replacing Na+. Finally, V3O8− is polymerized into V6O162− to keep the crystal structure stable.

Study of Forms of Compounds of Vanadium and Other Elements in Samples of Pyrometallurgical Enrichment of Ash from Burning Oil Combustion at Thermal Power Plants

“…According Zhang et al, oxides V 2 O 5 and V 3 O 16 in vanadium converter slag after roasting with CaO are poor soluble in (NH 4 ) 2 CO 3 solutions [ 54 ], and vanadium is deposited in the form of vanadate NaV 3 O 8 ·H 2 O [ 55 ]. The presented phases have a different composition and structure, which leads to a difference in solubility.…”

Functional materials for aqueous redox flow batteries: merits and applications

“…However, the performance of all-Fe RFBs is limited by the intrinsic pH of electrolytes, as most stabilized Fe-based functional materials are pH dependent. 91 In low pH medium (pH 0), the anode potential is lower than that of the HER, while the high pH medium (42) results in unexpected hydrolysis (Fig. 7a).…”

“…4d). 42 Although electrolyte design has since undergone many developments, these methods have their own limitations. Modifying the composition of the electrolyte can lead to vanadium electrolyte with superior chemical and electrochemical properties such as solubility, stability, and ionic conductivity.…”

Extraction of Rhenium and Osmium from Lead Technogenic Raw Materials of Copper Production

“…From the given solution, rhenium can be extracted by sorption-desorption methods on ions [23] or on a sorbent obtained from rice husk [24], precipitation with ammonium salts [25], and also by extraction-re-extraction. In our case, rhenium was extracted in the form of ammonium perrhenate corresponding to AP-00 grade by extraction and reextraction.…”