【作者】 王斐斐；

【导师】 仲剑初；

【作者基本信息】 大连理工大学 ， 化学工艺， 2012， 硕士

【摘要】 硼矿是一种比较稀缺的化工矿物资源,主要作为生产硼酸和硼砂的原料。以硼酸等为原料生产的各种硼化合物,广泛应用于化工、轻工、医药、电子、冶金、航天航空、电力、太阳能、核工业及农业等多种领域。因此,硼矿在国民经济中具有十分重要的作用。在我国,过去几十年来依赖的硼镁矿资源,由于长期的开采已面临枯竭,不能满足未来硼工业的需求。因此,加快其它硼资源的合理开发利用,对于我国硼工业的发展有着重要的现实意义。本文研究内容由两部分构成：以土耳其硬硼钙石矿为原料,探讨其硫酸分解制硼酸的工艺过程；以玻利维亚钠硼解石矿为原料,通过洗矿脱除氯化物后,对其硫酸分解制备硼酸的工艺过程进行研究。对土耳其硬硼钙石矿进行化学分析和物相表征,确定矿中各组分的含量为B2O341.82%、CaO26.75%和MgO1.71%；矿石主要物相为硬硼钙石(2CaO·3B203·5H2O)、钙磷石、硅硼石和硅酸盐等不溶性杂质。通过考察酸量、反应温度、反应时间和液固比等因素对酸解过程的影响,获得了硬硼钙石矿酸解制备硼酸的适宜工艺条件：酸用量为理论值的98%,反应温度90℃,反应时间1h,反应液固比4：1；在此条件下,硼的浸出率达到了98.16%。通过对母液和矿渣洗液的循环试验考察,确定系统经二次循环后,对硼酸母液进行回收硼的处理较适宜；硬硼钙石矿酸解产生的硼酸母液中硼,采用加Ca(OH)2反应转化法进行回收,最佳工艺条件为：温度25℃、钙硼比1.6：1、反应时间1.5h；经XRD物相分析,沉淀产物主要为四水合偏硼酸钙,其B203质量分数为28.38%,CaO质量分数为36.21%,MgO质量分数为2.50%。硬硼钙石矿酸解料浆中,渣的主要成分CaSO4·2H2O和未反应的钙磷石等,采用阴离子型聚丙烯酰胺进行助滤,可以改善CaSO4·2H2O的晶体尺寸,加快过滤速率,缩短过滤时间。玻利维亚钠硼解石矿的分析和表征表明：矿石中各组分含量为B2O325.31%、CaO12.36%、Na2O7.09%、MgO2.21%和Cl-4.95%,主要物相为钠硼解石(NaCaB5O9·8H2O)、 NaCl和SiO2。用矿粉质量6倍的去离子水洗矿,可使矿石中Cl-含量降到0.91%。用钠硼解石矿制硼酸的适宜工艺条件：酸用量为理论值的84%,反应温度90℃,反应时间1h,反应液固比3：1；在此条件下,硼的浸出率达到98.5%。通过母液和矿渣洗液的循环试验,确定二次循环后对硼酸母液进行回收硼的处理较适宜；采用向硼酸母液中加氢氧化钙沉淀偏硼酸钙的方法回收硼,适宜的回收硼的工艺条件为：室温(18℃)、钙硼比3：1、反应时间3h,沉淀产物主要为四水合偏硼酸钙。更多还原

【Abstract】 As a relative scarce chemical mineral resource, boron mineral is mainly used as the raw materials of boric acid and borax. A variety of boron compounds with using boric acid as raw materials have been widely used in many fields such as chemical industry, light industry, pharmacy, electronic, metallurgy, aerospace, power, solar energy, nuclear industry, agriculture and so on. Therefore, boron minerals play a significant role in the national economy. Ascharite resource which is the main resource in our country over the past few decades has run out due to a long period of mining, and can’t meet the needs of future boron industry. As a result, to speed up rational utilization of other boron resources is meaningful to the development of boron industry in our country. The research topics in this paper have two parts:the research on the chemical engineering process of boric acid preparation by using sulphuric acid to decompose Turkey’s Colemanite Ore, and the research on the decomposition process of Ulexite Ore in Bolivia by using sulphuric acid, with the removal of chloride by washing ore.Turkey’s Colemanite Ore was characterized by chemical analysis and XRD, and the chemical composition of Colemanite Ore is as follows:B2O341.82%, CaO26.75%and MgO1.71%. Colemanite Ore is mainly composed of Colemanite (2Ca0·3B203·5H2O), brushite, jennite and insoluble impurities such as silicate. The effects of liquid to solid ratio and sulfuric acid consumption on the reaction of Colemanite Ore with sulfuric acid were investigated and the results indicated that under the conditions of98%sulfuric acid theory consumption, temperature90℃, reaction time1h and reaction liquid to solid ratio4:1, the boron leaching rate could reach up to98.16%. With the reaction of Colemanite Ore with sulfuric acid carried out under these conditions, mother liquor and washing water recycles have been investigated, the experiment data showed that the better cycle time is secondary. The recovery process of boron from the mother liquor by the reaction of calcium hydroxide with boric acid has also been investigated and the results indicated that under the conditions of temperature25℃, CaO/B2O31.6:1, reaction time1.5h calcium metaborate can be precipitated, after characterizing by chemical analysis, the contents of different components were showed as follows:B2O328.38%, CaO36.21%and MgO2.50%. After the reaction of Colemanite Ore with sulfuric acid, CaSO4·2H2O was formed with brushite in the reaction slurry. Adding anionic polyacrylamide for filter aid can improve the filtration of the reaction slurry due to forming CaSO4·2H2O with larger crystal size, the filtration rate has been sped up, and the filtration time hass been shorten. Bolivia’s Ulexite Ore was characterized by chemical analysis and XRD, the chemical composition of Ulexite Ore is as follows:B2O325.31%, CaO12.36%, Na2O7.09%, MgO2.21%and Cl-4.95%. Ulexite Ore is mainly composed of Ulexite (NaCaB5O9·8H2O), NaCl and SiO2. After washing with deionized water, the content of Cl-can be reduced to0.91%. The results on the reaction of Ulexite Ore with sulfuric acid indicated that under the conditions of84%sulfuric acid theory consumption, temperature90℃, reaction time Ih and reaction liquid to solid ratio3:1, the boron leaching rate could reach up to98.5%. Mother liquor and washing water recycles have been investigated, the experiment data showed that the better cycle time is secondary. The recovery process of boron from the mother liquor by the reaction of calcium hydroxide with boric acid has also been investigated and the results indicated that under the conditions of temperature18℃, CaO/B2O33:1, reaction time3h calcium metaborate can be precipitated.更多还原