CAJ | 학술논문

高铬红土型铝铁复合矿经钠盐还原焙烧－磁选－浸出后，铬等有价金属在赤泥中富集（Cr2 O3含量达到3％～30％），属难熔复合矿物，目前主要以化学分析方法为主，但操作复杂，且步骤繁琐，分析周期长。而应用X射线荧光光谱法分析测定，一般采用钠盐熔剂、较高稀释比等熔融制样，不利于钠及低含量元素的测定。本文采用四硼酸锂－偏硼酸锂（67∶33）作混合熔剂，硝酸铵作氧化剂，饱和溴化锂溶液作脱模剂制备玻璃熔片，建立了波长色散型XRF测定高铬赤泥中主次量组分（铬硅铝铁镁钙钠钾硫磷钛锰钒）的分析方法。研究表明，熔样稀释比低于24∶1时，稀释比越低，对铂金坩埚腐蚀越严重；稀释比在24∶1时，制样方法的相对标准偏差（RSD，n＝10）最低；熔样时间越长，温度越高， RSD越低。由此确定熔样最优条件为稀释比24∶1，熔样时间15 min，熔样温度1 100℃。分析中采用铬铁矿、铝土矿、黏土、铁矿石国家标准物质及人工标准样品校准，基本参数法进行基体校正，方法精密度（RSD，n＝10）为0．3％～3．9％。与国内外其他含铬矿物的XRF分析方法相比，本方法采用不添加钠盐、一次熔片、常规熔样温度（1 100℃）、低稀释比（24∶1）等进行制样，制样方法的精密度和分析精密度均低，解决了高铬赤泥的XRF分析方法问题，还可扩展到高铬、铝、硅、铁等复合矿原矿及其钠盐处理焙烧矿、精矿及尾矿的XRF分析。
고락홍토형려철복합광경납염환원배소－자선－침출후，락등유개금속재적니중부집（Cr2 O3함량체도3％～30％），속난용복합광물，목전주요이화학분석방법위주，단조작복잡，차보취번쇄，분석주기장。이응용X사선형광광보법분석측정，일반채용납염용제、교고희석비등용융제양，불리우납급저함량원소적측정。본문채용사붕산리－편붕산리（67∶33）작혼합용제，초산안작양화제，포화추화리용액작탈모제제비파리용편，건립료파장색산형XRF측정고락적니중주차량조분（락규려철미개납갑류린태맹범）적분석방법。연구표명，용양희석비저우24∶1시，희석비월저，대박금감과부식월엄중；희석비재24∶1시，제양방법적상대표준편차（RSD，n＝10）최저；용양시간월장，온도월고， RSD월저。유차학정용양최우조건위희석비24∶1，용양시간15 min，용양온도1 100℃。분석중채용락철광、려토광、점토、철광석국가표준물질급인공표준양품교준，기본삼수법진행기체교정，방법정밀도（RSD，n＝10）위0．3％～3．9％。여국내외기타함락광물적XRF분석방법상비，본방법채용불첨가납염、일차용편、상규용양온도（1 100℃）、저희석비（24∶1）등진행제양，제양방법적정밀도화분석정밀도균저，해결료고락적니적XRF분석방법문제，환가확전도고락、려、규、철등복합광원광급기납염처리배소광、정광급미광적XRF분석。
Cr and other valuable metals are enriched in red mud (Cr2 O3:3%-30%)when high-Cr red clay type Al-Fe composite ores are comprehensively utilized by sodium reduction roasting-magnetic separation-leaching.High-Cr red mud belongs to refractory ore whose analysis methods are dominated by chemical analysis,which is a well-established but complicated procedure.High-Cr red mud can also be analyzed by X-ray Fluorescence Spectrometry (XRF).However,a use of sodium flux and a high dilution ratio are not conducive to sodium and low content elements.In this paper,a method of XRF analysis is developed for the determination of the major and minor components (Cr,Si,Al,Fe,Mg,Ca,Na,K,S,P,Ti,Mn and V)in high-Cr red mud by fused bead preparation with Li2B4O7-LiBO2(67∶33)flux,NH4NO3 oxidizer and saturated LiBr solution parting medium.When the dilution ratio of the melting sample is lower than 24∶1 ,the lower dilution ratio,the more serious is the corrosion on the Pt-Au crucible;the RSD (n=1 0)of the sample preparation method is at a minimum when the dilution ratio is 24∶1;the longer the melting time and the higher the melting temperature,the RSD becomes lower.The optimization conditions of fused bead are obtained when the dilution ratio is 24∶1 ,the melting temperature is 1 1 00℃ and the melting time is 1 5 min.The working curve was established by chromite,bauxite,clay,iron ore standards and manual preparation standard materials.The matrix effect and spectrum line overlap interference were corrected by a fundamental parameter method and standard regression.The results are consistent with certified values and the RSD (n=10)is from 0.3% to 3.9%.Compared with domestic and foreign XRF methods for chromium-containing minerals,this method uses no sodium salt,a fuse piece,conventional sample melting temperature (1 1 00℃),low dilution ratio (24 ∶1 )for sample preparation,and the sampling precision and analysis precision are low.The problem with XRF analysis of high-Cr red mud has been solved by this method,which can be used to analyze Cr,Al, Si and Fe in roasting,concentrates and tailings and other ores processed by sodium.