共查询到19条相似文献,搜索用时 156 毫秒
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研究了用双硫腺比色法测定磷肥、磷矿石中的汞。试样经王水溶解,在弱酸性介质中,双硫腺与汞(Ⅱ)生成橙红色的配合物,该配合物溶于四氯化碳或二氯甲烷中显色较稳定。回收率在95% ~103%之间,标准偏差在0. 1% ~0. 2%之间,方法用于几种磷肥、磷矿石的测定,结果满意。 相似文献
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采用原子吸收光谱法连续测定磷矿石和磷精矿中钾、钠。结果表明,该法与电感耦合等离子法(ICP)测试结果对比无显著差异,方法简单,可行,成本低,值得推广。 相似文献
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磷矿石和磷精矿中二氧化硅含量的仲裁方法为GB/T 1873-1995《磷矿石和磷精矿中二氧化硅含量的测定重量法》。采用微波碱熔消解磷矿石和磷精矿代替高温设备消解,通过正交实验找出了最佳碱熔消解条件,结果表明,实验方法节能易操作,安全成本低,不使用高温设备,能减少环境污染,易于推广等特点。与GB/T 1873-1995方法测定结果相比较,无显著性差异,绝对误差在0.05~0.16之间,相对标准偏差RSD=1.2%,回收率在95.00%~100.86%。 相似文献
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以云南海口磷矿为原料,试验优化研究磷酸浓度、反应温度、反应时间、磷酸加入量、磷矿粉细度、返料比、原料磷酸含固量等工艺控制条件对料浆法生产重钙磷矿分解率和产品质量的影响,得出优惠工艺条件和用活性较差的云南海口磷矿只能生产一等品重钙的结论。并提出:提高二次磷矿细度、反应温度,适当延长反应时间,适当提高造粒、干燥温度以提高磷矿分解率;认为:用料浆法工艺生产重钙时,选择活性好、品位低一些的磷矿比选择品位高,但活性差的磷矿更经济合理。 相似文献
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ICP-AES法测定磷矿中的氧化锶 总被引:1,自引:0,他引:1
采用HNO3-HF—HClO4混酸溶样后,直接用ICP—AES法快速测定磷矿中氧化锶含量。该法在选定Sr的分析线为407.771nm处干扰很小,检出限为0.0012μg/mL,相对标准偏差为0.79%,具有抗干扰能力强、线性范围宽、精密度高、结果准确等特点。 相似文献
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结合红磷公司的半水二水再结晶浓酸工艺磷酸装置多年使用不同磷矿的生产情况,评析磷矿石组成对半水二水(二步法)再结晶浓酸工艺产生的影响,并给出此工艺磷矿应使用的一些操作控制建议。 相似文献
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《分离科学与技术》2012,47(6):1645-1648
Abstract Only MazidaB phosphate are worthy of processing among the phosphate reserves in Turkey. The benefication problem of low-grade Mazidagi phosphates has not been solved, although they constitute 260 million tons out of a total of 400 million tons of phosphate rocks in the region (1, 2). The method used for the benefication of calcerous phosphates is generally calcination at about 800–950°C followed by slating and removal of small particles. Application of this common process gives a highly concentrated end product. When this method is used on the phosphate rocks of Mazidagi, it is not possible to obtain good quality products for industrial purposes. However, in some countries, to remove the excess amount of Ca(OH), solutions of NH4Cl and NaCl are used (3, 4). These compounds increase the solubility of Ca(OH), about three times. If a solution of sugar is used instead of those solutions 相似文献
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Zafar Iqbal Zafar M. M. Anwar D. W. Pritchard 《Nutrient Cycling in Agroecosystems》1996,46(2):135-151
As high grade deposits of phosphate rock are being depleted day by day in the world, future sources will be derived from low grade rocks containing various impurities. Low grade phosphate rocks are not suitable for direct use in acidulation plants unless their tricalcium phosphate (TCP) content is increased to 70% or more, using conventional methods such as crushing, screening, and drying, or some other physical separation process which include washing and desliming. Other special beneficiation techniques may also be applied, such as calcination, flotation and leaching before taking it as feed for the phosphatic industry.Most of the phosphate rocks are of sedimentary origin with low grade phosphate elements and higher levels of impurities. The first challenge to phosphate industry is the reduction of impurities in rock so that it is suitable for the production of phosphatic fertilizers to meet the increasing demand for phosphate and to cover the depletion of more amenable reserves in the world. This article addresses itself to this challenge: it considers the beneficiation methods for low grade phosphate rocks. 相似文献