發(fā)布時(shí)間：2018-05-21 19:54

  本文選題：廢棄SCR催化劑 + 有價(jià)金屬�。� 參考：《華北電力大學(xué)》2015年碩士論文

【摘要】：廢棄SCR催化劑中含有V、W和Ti等多種有價(jià)金屬,直接棄置不僅會(huì)造成環(huán)境污染,還會(huì)造成資源的浪費(fèi),因此回收其中的有價(jià)金屬具有重大意義。本文采用濕法冶金的方法,通過NaOH堿性浸出法一次性浸出廢棄催化劑中的V和W,余下未溶解的固體主要成分為二氧化鈦,從而將Ti分離;然后對(duì)浸出液進(jìn)行鈣化沉淀,通過甲酸選擇性浸出鈣混合沉淀物中的釩,經(jīng)過除雜,加入氨水釩將以偏釩酸銨的形式沉淀出來;甲酸浸出后沉淀物中的鎢,加入鹽酸轉(zhuǎn)化為鎢酸,經(jīng)過灼燒,最終生成三氧化鎢。通過實(shí)驗(yàn)確定NaOH堿性浸出法最佳工藝條件為:對(duì)于釩,NaOH濃度為20%,固液比1:7,催化劑粒徑125~180μm,溫度50℃,浸出時(shí)間60min,釩的浸出效率達(dá)93%以上;對(duì)于鎢,NaOH濃度為30%,固液比1:7,催化劑粒徑125~180μm,溫度60℃,浸出時(shí)間60min,鎢的浸出效率達(dá)87%以上。對(duì)于甲酸選擇性浸出過程,最佳反應(yīng)條件為:溫度30℃、pH=5、固液比1:5、反應(yīng)時(shí)間40min,釩的浸出率為94.88%,同時(shí)鎢的浸出率(損失率)僅為3.99%。從原料到產(chǎn)物釩和鎢最終的回收率分別為:82.25%和78.48%,鈦(含雜質(zhì))回收率超過99%。
[Abstract]:There are many valuable metals in the waste SCR catalyst, such as VN W and Ti, which will not only cause environmental pollution, but also cause waste of resources. Therefore, it is of great significance to recover the valuable metals. In this paper, using hydrometallurgical method, V and W in the waste catalyst were leached in one time by NaOH alkaline leaching method. Titanium dioxide was the main component of the remaining undissolved solid, and Ti was separated, then the leaching solution was calcified and precipitated. After selective leaching of vanadium from calcium mixed precipitate by formic acid, adding ammonia water vanadium will precipitate in the form of ammonium metavanadate; after formic acid leaching, the tungsten in the precipitate is converted into tungstic acid by adding hydrochloric acid, and after burning, the vanadium in the precipitate will be precipitated in the form of ammonium metavanadate. Finally, tungsten trioxide is formed. The optimum technological conditions of NaOH alkaline leaching method are as follows: for vanadium NaOH concentration 20, solid to liquid ratio 1: 7, catalyst particle size 125 ~ (180) 渭 m, temperature 50 鈩，

本文編號(hào)：1920538