X射线荧光光谱法测定铜矿石主次成分和铝土矿的生物冶金研究

【作者】 曹慧君；

【导师】 李晓宁； 梁逸曾；

【作者基本信息】 中南大学 ， 分析化学， 2010， 硕士

【摘要】 现代X射线荧光光谱分析是对各种物料进行多元素同时测定的一种通用测量方法。由于其快速分析、制样简单、重现性好、准确度高、非破坏性和对环境无污染等特点,被广泛应用于多领域的样品分析,但应用于铜矿石的分析研究较少。作者通过试验,拟定了粉末压片法和熔融法样品制备条件,采用国家标准样品和人工合成标准样品来绘制标准曲线,分别用波长色散XRF仪测定铜矿石样品中主次成分。发现采用压片法时,样品粉碎至74μm以下(通过200目筛子),硼酸粉末粘结剂镶边衬底,压片后进行检测,主量组分的分析结果稍差,微量组分的精密度和准确度能满足铜矿石分析要求；采用熔融法时：选择四硼酸锂-偏硼酸锂(m／m=12：22)混合熔剂,硝酸钠做氧化剂,样品与氧化剂的比例为1：4,混合样品与混合熔剂的比例为1：7,样品在600℃预氧化后加入2滴饱和的溴化锂脱模剂,在1050℃下熔融15min,制成熔片进行测定,在选定条件下,样品的分析结果与认定值相符,主量组分的精密度能够满足铜矿石中主次成分的分析需要。一些微生物通过代谢产物中的有机酸对矿物的浸蚀和对被溶解金属的螯合作用,可以从铝土矿中浸出铝和铁。在本研究中进行了生物一化学联合法浸出铝土矿中的铁和铝土矿中的铝的研究。发现,用黑曲霉素YJY-1#菌株的发酵液在80℃-90℃下浸出含铁铝土矿石,矿石中的Fe203含量可以由4.96%下降到2.87%。如果用2%的硫酸将微生物发酵液酸化到pH为0.5左右,然后浸出含铁铝土矿石,矿石中Fe203含量下降到0.39%。采用同样的方法浸出某低品位三水铝石,发现矿石在525℃下焙烧4小时后,在80℃-90℃下浸出10小时,每2小时后更换新的浸矿剂,矿石中铝的浸出率可达到90.99%。更多还原

【Abstract】 Modern X-ray fluorescence spectroscopy is a common measurement method of multi-elements simultaneous determination from various materials.Due to its rapid speed, simple sample preparation, reproducible, accurate, non-destructive, and environmental, it is widely used to analyzed sample in a variety of areas, but less applied to the analysis of copper ore. Powered press and fusion condition was provided to prepare samples.The major and minor components of the copper ore samples were determined by Wavelength dispersive XRF.It was Found that when powered press were selected, samples crushed to 74μm below (through 200 mesh sieve) and pressed with boric acid as margin band and underlaying the substrate, tested, the major components analysis results were somewhat unreasonable. But the precision and accuracy of minor components could meet the analytical requirements of copper ore. With fusion method, lithium tetraborate-lithium metaborate(m/m=12:22)as flux,sodium nitrate as oxidant, sample and oxidant ratio 1:4, mixed sample and flux ratio 1:7, sample pre-oxidation at 600℃after adding 2 drops of saturated lithium bromide as releasing agent, fused at 1050℃for 15min, the made glass disc was determined. Based on the selected conditions, the sample analysis results accorded with the certified values.And the precision of major components could meet the analysis needs of the copper ore components.Biometallurgy is a new technology, which mineral is used as energy substance of microorganism by metabolize action or value metals are leached from mineral by the metabolite,Iron or aluminum was leached from different bauxite by some microorganism in the way of organic acid of metabolite etching ore and chelating dissolved metalline ions.The calibration curve was plotted with national standard sample and artificially synthesized standard sample. In this study, the iron of the bauxite containg iron was removed by biochemistry leaching method, while alluminum of low-grade bauxite was leached. It was found that when the bauxite containing iron was leached by the Aspergillus niger numered YJY-1# zymotic fluid under temperture 80℃-90℃,the Fe2O3 content can be removed from 4.96% to 2.87%. If using 2% sulfuric acid added to the zymotic fluid and pH lowed to 0.5, then the Fe2O3 content in the ore decreased to 0.39%. The same method used to leach aluminum in low-grade gibbsite ore, it was found that when the ore was calcined under temperture 525℃for 4 hours, then leached for 10 hours under 80℃-90℃,the leaching agent changed every 2 hours, the aluminum leaching rate reached 90.99%.更多还原