Clean manufacturing technique of extracting vanadium pentoxide from vanadium-contained stone coal

Abstract

The invention discloses a clean manufacturing technique of extracting vanadium pentoxide from vanadium-contained stone coal, comprising the following steps: grinding the vanadium-contained stone coal until the granularity is less than 2mm, baking in the industrial microwave device at temperature of 700 to 800 DEG C for 1h to 2h, fine grinding the clinker after baking until the granularity is less than 0.15mm, adding water to prepare ore slurry, in which the volume mass ratio of water to vanadium-contained stone coal is 1-1.5 to 1, adding sulphuric acid to leach at temperature of 80 to 95 DEG C for 2h to 20h, in which the amount of sulphuric acid is 10% to 25% of vanadium-contained stone coal, adding ferrous powder in the extract to reduce ferric ion, adjusting the pH value with lime and ammonia water to be 2.8 to 3.0, and obtaining ammonium polyvanadate precipitate after solvent extraction, oxidization and adding ammonia water. The ammonium polyvanadate is calcined to prepare powdery vanadium pentoxide product. The invention has beneficial effects of 1. effectively breaking structures of minerals such as vanadium-contained mica and kaolin by using microwave device to roast the vanadium-contained stone coal; 2. compared with stone coal direct acid leaching technique, reducing sulphuric acid amount by 10% to 15%, as the sulphuric acid amount when acid leaching is 10% to 25% of mineral mass; and 3. without any additive in the baking process or air pollution, belonging to clean manufacturing technique.

Description

technical field

[0001] The invention relates to a clean production process for extracting vanadium pentoxide from vanadium-containing stone coal mines. Background technique

[0002] Vanadium-bearing stone coal mine is the main vanadium-containing resource exploited as a single vanadium deposit in my country, V 2 o 5 The grade is low, generally around 1.0%. The vanadium in stone coal is mainly V(III), some V(IV), and rarely V(V). Since the ionic radius (74pm) of V(III) is equal to that of Fe(II) (74pm), and is also very close to the ionic radius (64pm) of Fe(III), V(III) hardly generates its own Minerals, but exist in the silicon-oxygen tetrahedral structure of iron-aluminum minerals such as vanadium-containing mica and kaolinite in the form of isomorphism. Vanadium in stone coal can only be transformed into soluble pentavalent vanadium under the action of high temperature and additives. my country began to study the extraction of vanadium from stone coal in the 1960s, a...