氟表面活性剂和氟聚合物(V)——PFOS的短碳氟链替代品

主要介绍PFOS的短碳氟链替代品,分析短碳氟链产品作为替代品的可行性依据、性能和环境行为,进一步讨论短碳氟链替代品的研究进展和优化策略,并指出短碳氟链产品当前面临的问题。     

Fine coal desulphurization by leaching with bromine containing hydrobromic acid

Sulphur extraction from coal by leaching with bromine-containing aqueous hydrobromic acid has been investigated in the temperature range from ambient to 120 °C. This procedure was found to be selective for the removal of high levels of sulphate and pyritic sulphur within a few minutes of leaching, while no significant reduction of the organic sulphur could be observed. Leaching led to an appreciable reduction of the ash yield and the up-take of substantial quantities of bromine. The bromine can be removed as hydrogen bromide by thermal treatment under nitrogen, without significant loss of volatile matter; for reduction of the bromine level to below 0.1 wt%, treatment for at least 1 h at ≈ 500 °C was needed.     

氯化物介质矿浆电解法浸出硫化铜精矿

研究了在ＦｅＣｌ３ＨＣｌＮａＣｌ体系中直接电解浸出硫化铜精矿矿浆制取铜粉的工艺条件及机理。试验表明，在阳极初始溶液含Ｆｅ３＋６０ｇ／Ｌ、ＨＣｌ３０ｇ／Ｌ、ＮａＣｌ１５０ｇ／Ｌ，阴阳极电流密度分别为３５０和６００Ａ／ｍ２，１００℃的条件下浸出５ｈ，可获得铜浸出率９８．８％、渣含铜０．３４％、铜粉纯度９７．５％的结果；Ｆｅ３＋浓度是影响铜浸出率最显著的因素，阳极上发生的主要反应是Ｆｅ２＋的氧化；元素硫产生的机理是酸直接分解黄铜矿生成Ｈ２Ｓ，Ｈ２Ｓ溶解后再被Ｆｅ３＋氧化。     

硫酸介质中氯化物参与下氧化浸出铜渣过程

研究了镍铳选择性氧化浸出产生的铜渣在硫酸介质中氯离子参与下的氧气氧化浸出,考察和比较了氯化物用量、氧气流量、硫酸浓度、温度等因素对铜和镍浸出的影响,并讨论了其原因,确认了在硫酸介质中加入少量氯化物即可在常压下用氧气有效地浸出主要由辉铜矿或类似的硫化铜矿物组成的铜渣。     

砷酸铜制备工艺过程热力学分析

绘制了Cu-As-H2O系电位－pH图、不同As浓度下lg[Cu]T[As]T)-pH图以及Fe-As(V)-H2O系lg[Fe]T-pH图等,分析了由墨铜渣制备胂酸铜过程的热力学。酸性氧化浸出可同时浸出Cu和As,pH＝2左右脱脱铁率可达99％以上。铜砷比和pH值的不同,可以得到不同形式的砷酸铜;CuHAsO4,Cu2AsO4OH,Cu5H2(AsO4)。在胂酸铜制备工艺条件下,所得砷酸铜分子式为Cu5H2(AsO4)4。热力学分析结果与XRD相一致。     

Studies on Acid Leaching Methods for Fine Metal Powder Production

１ＩｎｔｒｏｄｕｃｔｉｏｎＭｅｔａｌｐｏｗｄｅｒｓａｒｅｉｎｇｒｅａｔｄｅｍａｎｄｆｏｒｄｉｖｅｒｓｅａｐｐｌｉｃａｔｉｏｎｓｉｎｔｈｅｉｎｄｕｓｔｒｙ．Ｍａｎｙｍｅｔａｌｃｏｍｐｏｎｅｎｔｓａｒｅｃｏｍｍｅｒｃｉａｌｙｍａｄｅｉｎｂｕｌｋｑｕａ...     

γ-聚谷氨酸-天冬氨酸聚合物的合成表征及性质

利用微生物发酵制备γ-聚谷氨酸,降解得小分子γ-聚谷氨酸,将天冬氨酸接入小分子γ-聚谷氨酸,得γ-聚谷氨酸-天冬氨酸聚合物(GAP460).核磁共振、红外光谱、差热扫描量热分析(DSC)等方法表征GAP460;常规方法检测GAP460的结构稳定性,免疫原性,急性毒性及血液参数值等.结果表明,成功制备了γ-聚谷氨酸-天冬...     

微波选择性加热在矿冶过程中的应用进展

微波由于其特殊的能量传递和转换方式,作为一种绿色的加热方式已经被广泛应用于工业生产。概述了微波加热原理和作用参数,从研究手段、处理过程和应用成果等方面评述了近几年来微波选择性加热在辅助磨矿、强化还原以及辅助浸出等冶金过程应用中的最新进展;最后提出了其存在的问题并展望了应用前景。     

油页岩制油残渣制备氧化铝及其铝浸出率的研究

以抚顺东露天油页岩制油残渣为原料,用酸提法制备氧化铝,采用单因素考察法确定了抚顺东露天油页岩残渣提取氧化铝的酸溶反应最佳工艺条件为:煅烧温度850℃,煅烧时间1h,所需原料粒度0.074mm,盐酸浓度为12%,液固比为5∶1,酸溶反应温度100℃,反应时间1.5h,各项工艺指标在最佳工艺条件下,Al2O3浸出率为81.75%;采用均相化学沉淀法由酸溶反应得到的氯化铝滤液制备氧化铝的最佳工艺条件为:反应温度55℃,偏铝酸钠浓度0.4mol/L,乙酸乙酯与铝离子物质的量之比为1.7∶1,反应时间1.5h,表面活性剂的用量为总体系质量的0.3%。采用激光粒度分布仪、X射线衍射仪、X射线荧光光谱仪对所制得的产物氧化铝进行了表征和分析研究。     

Evolution of the organic sulfur and other components during nitric acid leaching of Mequinenza coal

In this work, desulfurization by nitric acid leaching is studied in Mequinenza coal, whose characteristics are very low contents of sulfide and sulfate sulfurs in comparison with a very high content of organic sulfur that allows the selective attack on organic sulfur with regard to carbon to be clearly determined. Organic matter is made soluble at high temperatures and there is a threshold temperature for the same. The reaction involves an increase of nitrogen and oxygen, and a decrease of carbon contents. These variations reach a limit as the solubility of the organic matter progresses. The attack on inorganic sulfur is very fast, producing an initial leap as in the attack on organic sulfur, while the solubilization of organic matter is slower, because of which shorter times should be applied for the purpose of desulfurization.