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Reference to the results of previous studies, Hunan Guzhang County vanadium stone coal as raw material, the traditional method of roasting sodium vanadium leaching rate is not high technology transfer, environmental pollution, low resource utilization, this paper proposes double salt roasting - Low Acid Leaching - Ion exchange - ammonium vanadium precipitation process route, through the roasting process vanadium extraction systems research and on vanadium ion exchange process, ammonium vanadium precipitation process related Theory. Greatly improving the vanadium vanadium extraction yield, improved roasting (fire assay) vanadium environmental pollution problems for vanadium extraction industry proposed a suitable process parameters. The main contents and results are as follows: The experimental analysis of the composition of stone coal Guzhang, focusing on the stone coal stone complex salt roasting, low-acid leaching, ion exchange enrichment of vanadium and vanadium salts Shen process is studied, including the double salt type, double salt ratio, the amount of complex salt, baking time, calcination temperature and leaching liquid to solid ratio, amount of sulfuric acid leaching, leaching temperature, leaching time on the leaching rate of vanadium designed orthogonal scheme, the orthogonal experiment; The effects of D201 resin adsorption of vanadium (ⅴ) performance of static adsorption mechanism, and explore the D201 resin adsorption kinetics of vanadium; explored in a weak alkaline conditions, the initial concentration of partial vanadate, plus ammonium coefficient K, pH value, temperature and other factors on the sink rate of vanadium, in a suitable combination of conditions kinetics of precipitation, with the integral method to establish mathematical model to determine the vanadium precipitation kinetics parameters; and characterized by X-ray diffraction and infrared spectral analysis of the precipitated product was characterized; according to HG / T 3445-2003 analysis of ammonium metavanadate and vanadium pentoxide purity. Experiments show that: stone coal sample test showed that the mine containing 0.85% vanadium pentoxide, silica containing up to 75%, mainly vanadium sample roscoelite phase, are difficult to break vanadium-containing minerals. Calcination experiments show that the sodium chloride, sodium carbonate and sodium salt of a composite system compared to traditional process greatly reduces the amount of sodium chloride, to reduce exhaust gas pressure on the environment calcination, vanadium leaching rate can significantly improve the vanadium leaching rate is affected by the amount of the double salt, complex salt ratio, the calcination temperature, calcination time, the impact of the amount of acid leaching, the preferred process parameters are: the calcination temperature was 750 ℃, complex salt additive amount of 9%, calcination time 2h, leaching temperature of 50 ℃, plus 2% of the amount of acid leaching time 4h; Under this condition, vanadium leaching rate of 95% or more. D201 resin separation and enrichment using vanadium, at a temperature of 303K, pH value of 2.0, the concentration of vanadium pentoxide 12g · L -1 conditions, D201 resin adsorption saturation adsorption capacity of vanadium 306mg · g -1 ; vanadium solution flow rate of 0.02mL · min -1 · g -1 , the dynamic equilibrium adsorption capacity of 270mg · g -1 . Experiments show that the adsorption of D201 resin for vanadium meet Freundlish isotherm model, the vanadium exchange adsorption process followed pseudo two exchange adsorption kinetics; reaction order is intended to two, the adsorption rate increases with increasing temperature, the activation energy as 14.165KJ · moL -1 ; vanadium D201 resin adsorption process on particle diffusion process control steps. Eluent chloride process is more suitable for Shen Shen vanadium vanadium conditions: pH = 8.0, plus ammonium factor 2, the temperature 50 ℃, vanadium concentration 30g · L -1 , vanadium precipitation rate can be more than 99%; right ammonium vanadium precipitation kinetics studies have shown that the differential method using ammonium chloride deduced vanadium precipitation kinetics data, the reaction order n = 2, kinetic constant of 0.6 × 10 < sup> -3 (mol · dm -3 ) -1 · min -1 , ammonium metavanadate was prepared by two order reaction rate equation is r = 0.6 × 10-3 (ax) (bx); infrared spectra of the product precipitated with ammonium metavanadate standard pattern consistent; product structure by XRD analysis of single crystals of high purity; metavanadic Ammonium the calcined V 2 O 5 products, product quality indicators have been tested up to HG / T 3445-2003 standard for chemical powder vanadium; findings can give vanadium stone coal vanadium complex salt roasting industrialized reference.
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