【正文】 煉試驗(yàn)研究。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。在配碳量為13%—14%，還原溫度為1420—1450℃，—，一段還原可獲得鈮收率＞90%、脫磷率60%—80%、脫硫率為70%—90%的指標(biāo)。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(jìn)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(biāo)準(zhǔn)的鈮鐵(含60%—65%Nb)。因此，對(duì)粗鈮精礦進(jìn)行了工業(yè)分流試驗(yàn)，生產(chǎn)了不同品級(jí)的鈮精礦17t，首次在工業(yè)生產(chǎn)條件下得到具有實(shí)用價(jià)值的鈮精礦。根據(jù)質(zhì)量守恒，計(jì)算出模擬粗鈮精礦的化學(xué)成分。 磁化焙燒磁化焙燒是在還原劑（C、CO和H2）存在條件下把鐵礦石加熱到適當(dāng)溫度（550—750℃），此時(shí)赤鐵礦和褐鐵礦被還原為磁鐵礦。焙燒礦磁性最強(qiáng)。本文用磁選設(shè)備為SCQS74—Φ50型磁選管。如果不考慮溶液中有電子遷移，PHo可按下式計(jì)算：PHo=△Go/式中△Go為礦物和H+反應(yīng)的標(biāo)準(zhǔn)自由能變化；n為參與H+反應(yīng)的計(jì)量系數(shù)；R為氣體常數(shù)；T為反應(yīng)溫度。試驗(yàn)結(jié)果表明，在真空度小于10Pa、溫度為1300℃、保溫180min的條件下，可以合成鈮鐵礦和鈮鈣礦[2]。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。尾礦在高壓反應(yīng)釜中用鹽酸進(jìn)行酸浸，將未浸出固體用水清洗，抽濾、烘干，最終得到富鈮的浸渣。表明45min時(shí)還原反應(yīng)已經(jīng)基本結(jié)束，再延長(zhǎng)時(shí)間對(duì)還原無(wú)益。普通碳粉的氣化反應(yīng)起始溫度一般為800—900℃，依碳的種類、粒度、比表面積等性質(zhì)的不同而異。赤鐵礦的理論還原度（即，赤鐵礦全部被還原成磁鐵礦時(shí)的還原度）%。（a）原礦XRD（b）750℃、45min還原礦XRD（c）800℃、45min還原礦XRD圖（d）850℃、45min還原礦XRD （a）為原礦XRD圖。（a）中較強(qiáng)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(shí)符合。（d）中還出現(xiàn)了FeO的衍射峰，說(shuō)明850℃時(shí)部分磁鐵礦進(jìn)一步被還原成FeO。電流繼續(xù)增大，收率不再明顯增大而趨于穩(wěn)定。當(dāng)磁選電流足夠大時(shí)，這些與磁鐵礦燒結(jié)在一起的脈石也會(huì)進(jìn)入精礦中，造成精礦品位下降。說(shuō)明750℃還原45min時(shí)，磁化還原已經(jīng)基本結(jié)束。還原溫度對(duì)精礦指標(biāo)的影響有兩個(gè)方面：一方面，在不發(fā)生磁鐵礦過(guò)還原的前提下，升高溫度，促進(jìn)赤鐵礦的磁化還原，對(duì)提高收率有利；另一方面，升高溫度會(huì)強(qiáng)化低熔點(diǎn)脈石礦物與磁性鐵的燒結(jié)，導(dǎo)致精礦品位下降?？煽闯?，750℃，%。還原時(shí)間為25min和45min時(shí)，精礦品位接近，%，說(shuō)明045min范圍內(nèi)，還原產(chǎn)物主要是強(qiáng)磁性的磁鐵礦。經(jīng)不同激磁電流下磁選，—%，—%，—。試驗(yàn)所用粗鈮精礦中的主要礦物有白云石、方解石、磷灰石、鐵礦物和鈮鈣礦。%，%。 (4)本文設(shè)計(jì)的“還原焙燒—磁選—酸浸”工藝從粗鈮精礦中回收鐵并富集鈮的方法具有工藝流程簡(jiǎn)單、對(duì)有價(jià)元素回收率高的優(yōu)點(diǎn)，其研究結(jié)果為包頭白云鄂博礦鈮資源的綜合回收利用提供了一條新途徑。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 and it was mainly contaminated with sulfur, calcium and yttrium ().Table 4 Stripping of niobium from loaded extractant % TQ at O/A ratio of 1/1 for 15 minStripping agentH2O mol/L HF mol/L HFStripping efficiency/% Elemental position of precipitate formed from stripsolution as analyzed by scanning electron microscope Interfering elements extracted by TQThe major elements extracted by TQ from the sulfate leach liquor were cerium and yttrium with efficiency of 63% and %, respectively. Both elements were stripped with 20% sodium hydroxide. The extraction process was also interfered by % calcium, which was detected in the final product. Only % tantalum was transferred to the extractant while 4% uranium and % iron were extracted but none of the mentioned elements were stripped with mol/L HF.4 ConclusionsThis study demonstrated the potentiality of TQ in the extraction of niobium from sulfate leach liquor of Egyptian ore sample. The results of the bench scale extraction experiments showed that 84% of niobium was extracted by shaking equal volumes of % TQ in methylene chloride with leach liquor of [NbO2(SO4)3]3 in the organic phase. The mol/L HF was used to strip % niobium, which was precipitated by ammonium hydroxide with efficiency of %. The purity of the final product reached %.Thus, it is possible to utilize the synthesized TQ as an extractant in hydrometallurgical processes for separating niobium from sulfate liquor of Egyptian ore sample.用咪唑啉酮化合物從埃及礦硫酸浸出液中提取鈮1 緒論自然界中，鈮和鉭總是以復(fù)雜的氧化物共存，脈石礦物主要為結(jié)晶花崗巖。鈮一般來(lái)源于自然鈮礦物、進(jìn)口或者錫渣。唑類化合物作為重要的環(huán)狀系因?yàn)樗麄兊纳镄阅艿亩鄻佣艿街匾暋?,3雜環(huán)二酮的懸浮液在有DMF、DMA的情況下加熱三小時(shí)。 礦石性質(zhì)本實(shí)驗(yàn)所用礦樣為埃及東部Kadabora礦山得來(lái)，此礦山的礦為典型的復(fù)雜氧化礦。 鈮的回收率，所得懸浮液在150℃下攪拌兩個(gè)小時(shí)，不溶殘?jiān)^(guò)濾，所得濾液的化學(xué)成分在表2中給出。最后得到的產(chǎn)物用SEM分析其中的化學(xué)組成和純度。本次試驗(yàn)將檢驗(yàn)1,3環(huán)己酮對(duì)提鈮的效果，其浸出率不超過(guò)5%。值得提的是高度解離的礦對(duì)試驗(yàn)時(shí)有好處的。 A/O的影響，在不同油水度（從1/4—3/1）下振蕩15分鐘。當(dāng)TQ濃度再增加時(shí)浸出率沒有明顯的變化。%TQ以體積比3/1，%。所得濾渣洗滌過(guò)濾，然后加熱到900℃干燥。當(dāng)4%%的鐵被提取時(shí)，%的鉭也被提取。%。本論文所研究的內(nèi)容和書寫是在許多老師以及同學(xué)們的幫助下才得以順利進(jìn)行的，在此，我要衷心的感謝他們！首先，我要感謝我的指導(dǎo)老師布林朝克老師。試驗(yàn)后他又耐心的指導(dǎo)我書寫論文。再次