【正文】 The loaded organic phase assaying g/L niobium was shaken with the same volume of the following stripping agents: distilled water, mol/L HF and mol/L HF. The results given in Table 4 showed that mol/L HF stripped % of the loaded niobium. Two volumes of ammonia solution (33%) were mixed with one volume of mol/L HF strip solution to yield % precipitation efficiency. The solid product was filtered and thoroughly washed。這些對提鈮效果顯著地藥劑可以分為兩大類：一類是中性氧化萃取劑，如酮類、TBP、TOPO和亞砜；另一類為含長鏈脂肪族或芳香族的胺類化合物，如TOA、TBA等。接下來，在酒精中有氨基三唑的情況下反應六小時，隨后加入結(jié)晶態(tài)的pipredine。由蒸餾水、進行萃取鈮試驗。 硫酸濃度的影響、%提取劑TQ后振蕩15分鐘，隨著硫酸濃度的減小，%%。 TQ濃度的影響研究這個因素，別的條件如A/O定為1/1，接觸時間15分鐘，%%變化。表4的結(jié)果表明。實驗室提取試驗結(jié)果表明：%，鈮的提取達到84%。試驗前，我在他的指導下搜集了很多和本論文有關的專業(yè)方面的資料。再次，我還要感謝魏小磊同學，在試驗中得到他的協(xié)助和支持，有時我們共同探討，在此過程中，讓我學到了許多知識，在此表示感謝！另外，感謝本論文所引用的所有參考文獻的作者，感謝他們?yōu)楸菊撐牡膶懽魈峁┱鎸嵖煽康目茖W知識。本論文所研究的內(nèi)容和書寫是在許多老師以及同學們的幫助下才得以順利進行的，在此，我要衷心的感謝他們！首先，我要感謝我的指導老師布林朝克老師。當4%%的鐵被提取時，%的鉭也被提取。%TQ以體積比3/1，%。 A/O的影響，在不同油水度（從1/4—3/1）下振蕩15分鐘。本次試驗將檢驗1,3環(huán)己酮對提鈮的效果，其浸出率不超過5%。 鈮的回收率，所得懸浮液在150℃下攪拌兩個小時，不溶殘渣過濾，所得濾液的化學成分在表2中給出。1,3雜環(huán)二酮的懸浮液在有DMF、DMA的情況下加熱三小時。鈮一般來源于自然鈮礦物、進口或者錫渣。L1)Recovery/%69,83 Results and discussion Extraction experimentsCyclohexone was previously used for extracting 70% niobium from sulfate leach liquor in presence of ammonium nitrate. In the present study, 1,3 cyclohexane dione was examined for extracting niobium. Its extraction efficiency did not exceed 5% by shaking equal volumes of the organic phase and sulfate leach liquor ( mol/L H2SO4) containing g/L Nb for 15 min. Thisβdiketone was used as start for synthesizing TQ. The latter was prepared as % in methylene chloride and was used to study the influence of different extraction conditions in improving niobium extraction efficiency from the sulfate leach liquor. Effect of sulfuric acid concentrationFour leach liquors were prepared by digesting the ground ore sample with sulfuric acid of , , and mol/L. Equal volumes of these solutions were shaken for 15 min with the extractant % TQ. The extraction efficiency of niobium increased from % to % by decreasing the acid concentration, which may be due to the ability of TQ to extract sulfuric acid. The maximum distribution coefficient was at shows the plot of lg D versus lg [H2SO4],which is found to be linear with slope of about . It is probable that the following reaction may occur:Nb2O5+6H2SO4+5/2O2——2NbO2(SO4)3+6H2O (2) Logarithmic plot of Nb distribution ratio lg D vslg[H2SO4] Effect of contact timeThe aqueous leach liquor of mol/L sulfuric acid and the extractant % TQ were shaken at A/O ratio of 1/1 for varying periods of time ranging from 1 to 30 results showed that increasing the contact time had little influence on increasing the extraction efficiency of niobium and 15 min was adequate for the maximum extraction of niobium where % was achieved. Effect of aqueous/organic (A/O) ratioThe sulfate leach liquor of mol/L acid concentration containing g/L Nb was shaken with % TQ in methylene chloride for 15 min at different A/O ratios varied from 1/4 to 3/1. As shown in Table 3, the distribution ratio of niobium increased by increasing volume ratio of aqueous phase over the organic phase, thus the maximum Nb loading was occurred at ratio of 3/1.Table 3 Effect of A/O ratio upon extracting niobium by % TQ from aqueous solution of mol/L sulfuric acid and 15 min contact timeA/O ratio1/41/31/21/12/13/1Concentration in aquor (g%，%。經(jīng)不同激磁電流下磁選，—%，—%，—?？煽闯觯?50℃，%。說明750℃還原45min時，磁化還原已經(jīng)基本結(jié)束。電流繼續(xù)增大，收率不再明顯增大而趨于穩(wěn)定。（a）中較強的衍射峰除了CaF2和SiO2以外均屬于赤鐵礦，這與原礦中主要物相為赤鐵礦的事實符合。赤鐵礦的理論還原度（即，赤鐵礦全部被還原成磁鐵礦時的還原度）%。表明45min時還原反應已經(jīng)基本結(jié)束，再延長時間對還原無益。干燥后的片裝入剛玉坩堝，將剛玉坩堝放入ZT5020型真空管式爐中。如果不考慮溶液中有電子遷移，PHo可按下式計算：PHo=△Go/式中△Go為礦物和H+反應的標準自由能變化；n為參與H+反應的計量系數(shù)；R為氣體常數(shù)；T為反應溫度。焙燒礦磁性最強。根據(jù)質(zhì)量守恒，計算出模擬粗鈮精礦的化學成分。然后用鹽酸浸洗上述含鈮氧化物, 90%以上的鐵礦物、磷礦物以及CaO 和MgO進入浸液, 鈮幾乎全部留在浸渣中, 得到的浸渣含Nb2O5近30% ,Nb/Fe=6,Nb/P =12, 此浸渣可用于冶煉符合工業(yè)標準的鈮鐵(含60%—65%Nb)。采用“二步法”工藝處理包頭中貧氧化礦低品位鈮精礦是可行的。選擇性還原的目標是將鐵從氧化物中還原出來，鈮則仍保持氧化狀態(tài)，使鐵和鈮在熔分過程中分別進入金屬相和渣相，達到鐵鈮分離的目的。根據(jù)上述磁性差異，在原礦磨至選別鐵、稀土所需粒度（200目占90—95%）時采用弱磁選回收磁鐵礦；弱磁選尾礦進行強磁粗選，將赤鐵礦、稀土礦物及鈮礦物選人磁性產(chǎn)品，遺棄部分脈石礦物，完成有用礦物與脈石礦物的初步分離，并使原生和次生礦泥得到基本脫除。%、% 的稀選尾礦中, %、%、%%、%的鐵精礦。（1） 重選—反浮選—磁選—化學選礦[10]白云鄂博礦東部接觸帶2礦體鈮礦石中鈮鈣礦占鈮礦物總量的75%，黃綠石和鈮鐵礦分別占15%和10%，根據(jù)鈮礦物、鐵礦物和脈石礦物的密度、可浮性的不同，最終確定的選別工藝為重選—反浮選—磁選—化學選礦。鈮的這種隨粒級的質(zhì)量分數(shù)及分布特征為鈮的選別回收帶來了較大困難[18] 稀土區(qū)尾礦不同粒級中w（Nb2O5）及分布特征，%粒徑/μm+7474—+5050—+4040—+3030—+2020—+1010合計產(chǎn)率質(zhì)量分數(shù)分布量分布率一種資源是否可以有效回收利用，除取決于它所在給礦的性質(zhì)，即給礦礦物組成、礦物粒度、元素賦存狀態(tài)、元素及元素所形成礦物含量、以及礦物的解離、嵌布特征等外，還取決于這種元素所形成礦物的自身的工藝性質(zhì)。經(jīng)研究分析，白云鄂博礦中含鈮礦物主要為鈮鐵礦、黃綠石、鈦鐵金紅石和易解石四種。(5)鈮的分散程度較高。白云鄂博礦床的鈮資源具有下面一些基本特征[4]：(1)儲量大。（3） 作為超導體的應用近些年來，鈮的超導性引起了人們的重視，先后研制出了NbTi、Nb3Sn等超導合金。目前，含鈮的合金鋼有高強度低合金鋼（HSLA）,不銹鋼和耐熱鋼等，其中以高強度低合金鋼的用鈮量占得比重為最大。室溫下鈮在空氣中穩(wěn)定，在氧氣中紅熱時也不被完全氧化，高溫下與硫、氮 、碳直接化合 ，能與鈦、鋯、鉿、鎢形成合金。然而，粗鈮精礦在工業(yè)上不能直接應用。鐵和稀土已回收利用，鈮礦由于其貧、細、雜的特點，綜合回收難度非常大，經(jīng)過近半個世紀的研究，與鐵、稀土的開發(fā)利用相比，鈮資源綜合利用水平嚴重落后。20世紀80年代初，根據(jù)含鈮鐵精礦中鈮品位的高低，采用不同的回收利用鈮資源的方法；20世紀80年代末，長沙礦冶研究院設計了“弱磁—強磁—浮選”方案[3]，使得從強磁中礦浮選稀土的尾礦中綜合回收鈮的研究工作成為可能。關鍵詞：還原焙燒 磁選 酸浸 粗鈮精礦The experimental research of the extraction of Nb from coarse niobium concentrates by Magnetized roasting Magnetic separation acid leachingAbstractNiobium is an important strategic resources and it has important application in many industry fields. Niobium reserve in Baiyunebo mine is over 95% of the total amount of China. But the fine disseminated extent ,low grade ,a variety of niobium mineral cause Baiyunebo ore resources prehensive utilization has yet to realize indust realization. Based on the basis of previous work ,the experimental research of the extraction of Nb from coarse niobium concentrates by magnetized roasti