| Stone coal is an unique kind of vanadium-containing ore. Extraction vanadium is one of utilization ways of stone coal, but it caused the environment pollution by this mineral mining or residues. Therefore, it is of great significance for the comprehensive utilization of stone coal resources to reduce environment pollution.In this paper, mesoporous activate carbon was prepared from Chongqing stone coal by chemical activation with KOH. The experiment was mainly on the effects of the HF-H2SO4 acid pretreatment and KOH activation conditions on the preparation of activate carbon, and the samples were characterized by XRD, FT-IR, BET, SEM, EDS. The results showed that the optimum ratio of HF-H2SO4 acid pretreatment conditions: HF concentration was 15%, H2SO4 concentration was 15%, leaching temperature was 85℃, leaching time was 2h, the carbon content was increased from 26.71% to 74.76%, Si O2 content decreased obviously. KOH activation optimum conditions: the ratio of KOH to stone coal was 4, activation temperature was 800℃ and activation time was 1h. Dilute hydrochloric acid pickling and water boiling test could effectively remove impurities in the crude product of active carbon. Under these conditions, the specific surface area of active carbon was 1524.82 m2/g, mesoporous ratio was 94.28%, total pore volume was 0.74cm3/g, average pore size diameter was 2.4nm, methylene blue adsorption value was 792.93mg/g, the prepared sample was a stone coal-based mesoporous activate carbon with high purity.The influences of the ratio of KOH to stone coal, activation temperature and activation time on the methylene blue adsorption properties and yield were investigated. The sample was characterized by low temperature N2 adsorption. The results showed that the Mesoporous Coal-based activated carbons could be prepared when the ratio of KOH to stone coal was 4, activation temperature was 800℃ and activation time was 1h, which specific surface was 987.98 m2/g, total pore volume was 0.6016 cm3/g, the mesoporous ratio was 94.28%, average pore size diameter was 3.43 nm, methylene blue adsorption value was 497.79mg/g.This paper use solvent extraction to prepare vanadium from stone coal, vanadium was effectively leached during HF-H2SO4 pretreatment process. P204 was used as an extraction agent, TBP as a co-stripping agent, sulfonated kerosene as organic solvent, and the sample was subjected with XRD, FT-IR, XRF analysis tests, the results showed that the optimum ratio of organic phase was used for extraction: p H value of the aqueous phase should be controlled at about 2.5, 25% P204 +5% TBP +70% sulfonated kerosene, the prepared vanadium pentoxide(V2O5) content increased from 0.86% to 81.42%, Si O2 content decreased from 63.22% to 0.08%.V2O5 and Active carbon( AC) were extracted from stone coal. V2O5/AC photocatalyst was prepared by impregnation-roasting method. The property of the as-prepared composite was characterized by XRD, FT-IR, UV-vis, SEM and ASAP. The result showed that 70%V2O5/AC(adding 5% urea( CO(NH2)2)) had large specific surface area(702.20 m2/g).The average smaller particle size of V2O5 in the composite was smaller than those of pure V2O5 and 70%V2O5/AC-U(without CO(NH2)2). 70% V2O5/AC held strong adsorption ability. The photocatalytic performance and the cycling efficiency of as-prepared composites were studied by the photodegradation reaction of Rhodamine B(Rh B) under simulation sun light irradiation in five cycle employments. The degrading Rh B ratio was 90.2% within 3h in 200 ml Rh B solution(10mg/L) with 0.2g 70%V2O5/AC, the ratio of 70%V2O5/AC-U was 89.4% in 5h under other same condition. The degradation ratio of Rh B was 60.2% for the fifth recycle use of 70%V2O5/AC, and the recycle efficiency reached to 80.1% after five times repeatedly use. 70%V2O5/AC possessed high photocatalytic activity and reuse rate. By fitting V2O5/AC degradation of Rh B curve showed that the degradation reaction followed the first-order kinetics model. |
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