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快速连续提取沉积物中还原性无机硫的实验方法与应用 被引量:1
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作者 茅昌平 杜苏明 +3 位作者 贾志敏 于刚 王耀 饶文波 《岩矿测试》 CAS CSCD 北大核心 2023年第3期576-586,共11页
还原性无机硫是沉积物硫中最活跃的部分,其含量变化控制沉积物中铁、磷及重金属等元素的地球化学行为,在地质过程和环境污染方面都具有至关重要的影响。化学连续提取法是目前沉积物中硫形态提取基本方法,但常用的冷扩散法处理单个样品... 还原性无机硫是沉积物硫中最活跃的部分,其含量变化控制沉积物中铁、磷及重金属等元素的地球化学行为,在地质过程和环境污染方面都具有至关重要的影响。化学连续提取法是目前沉积物中硫形态提取基本方法,但常用的冷扩散法处理单个样品耗时长,难以实现对大批量样品的快速连续提取。为实现快速、准确地测定沉积物样品各形态还原性无机硫的含量,本文采用热蒸馏法,改进基于前人的三步提取过程,通过优化实验装置预先制备实验所需的二氯化铬溶液,实现了样品还原性无机硫形态的快速连续提取;以过氧化氢为氧化剂,将提取的各形态硫氧化为SO2-4后采用离子色谱进行检测。选取三峡库区沉积物样品进行重复实验检验,得到提取酸挥发性硫、黄铁矿硫、元素硫的标准偏差(RSD,n=3)分别为5.26%、1.22%和3.09%,重复性较好。进一步对酸挥发性硫、黄铁矿硫、元素硫的加标回收率进行测定,得到这三种硫形态的回收率分别为92.8%、93.6%、94.1%。本实验方法采用的热蒸馏法对单个硫形态提取时间为1.5h,用时较短,玻璃装置连接便捷、操作简单,分析检测准确度好,实现了一套装置对沉积物还原性无机硫形态的连续提取,可适用于大批量样品的硫形态快速提取与检测。 展开更多
关键词 还原性无机硫 热蒸馏法 硫形态提取 沉积物 离子色谱
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青海盐湖初级碳酸锂产品制备高纯金属锂研究 被引量:8
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作者 周园 韩金铎 +2 位作者 贾永忠 马培华 景燕 《稀有金属》 EI CAS CSCD 北大核心 2004年第2期343-345,共3页
在分析工艺原理的基础上 ,直接利用青海察尔汗别勒滩地区盐湖晶间卤水提取制备的粗品碳酸锂为原料 ,选用复合助剂 ,采用真空热还原 蒸馏技术 ,以CaO和Al2 O3的混合物为助剂 ,在 10 0 0℃ ,0 .13~ 1.3 3Pa真空下反应 5h ,制备了纯度≥ ... 在分析工艺原理的基础上 ,直接利用青海察尔汗别勒滩地区盐湖晶间卤水提取制备的粗品碳酸锂为原料 ,选用复合助剂 ,采用真空热还原 蒸馏技术 ,以CaO和Al2 O3的混合物为助剂 ,在 10 0 0℃ ,0 .13~ 1.3 3Pa真空下反应 5h ,制备了纯度≥ 99.95 %的高纯金属锂 ,其纯度可满足一般锂电池和锂合金对金属锂的纯度要求 ,而且生产过程能耗低、无污染、产品纯度高、收率高、工艺流程短、设备简单 ,具有明显的成本竞争优势。 展开更多
关键词 真空冶金 高纯金属锂 还原-真空蒸馏 碳酸锂 盐湖
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稀土及其应用的重要性 被引量:2
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作者 刘丽静 《内蒙古石油化工》 CAS 2004年第3期36-37,共2页
本文介绍了稀土的性质和主要生产工艺,以及其在各行各业中的重要作用。发展 稀土行业,前景广阔。
关键词 稀土 生产工艺 稀土元素 金属还原 金属还原蒸馏 熔盐电解 还原扩散
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Determination of Thermal Properties of Cuts and Residue Streams Obtained in the Molecular Distillation Process 被引量:3
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作者 Ballestemos Hernaindez Juhe Jardini Andre +2 位作者 Wolf Maciel Ma Regina Maciel Filho Rubens Medina Lilian 《Journal of Chemistry and Chemical Engineering》 2011年第8期684-690,共7页
A real-time sensing of the molecular distillation process temperature by a FLUKE brand thermograph Ti50 IR FlexCam and thermography technique was realized. After completion of the molecular distillation, three propert... A real-time sensing of the molecular distillation process temperature by a FLUKE brand thermograph Ti50 IR FlexCam and thermography technique was realized. After completion of the molecular distillation, three properties of heat transport chain cuts and residues obtained in the process were estimated by Differential Scanning Calorimetry (DSC) (specific heat, enthalpy, thermal conductivity). These properties are of great importance for improving oil characterization and for future modeling and simulation of the molecular distillation process. The results show that through the method of Differential Scanning Calorimetry, profiles have been obtained from the variation of specific heat, enthalpy and thermal condutivity as a function of temperature for samples of cuts from the distillation (ASTM D-2892) and fractions of distillate and residue from the process of molecular distillation. 展开更多
关键词 Molecular distillation heavy oil heat transport specific heat ENTHALPY thermal conductivity differential scanning calorimetry.
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Fractionation of Palm Kernel Oil by Short Path Distillation
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作者 Muhamad Roddy Ramli Siew Wai Lin +1 位作者 Luqman Chuah Abdullah Thomas Choong Shean Yaw 《Journal of Food Science and Engineering》 2014年第2期82-95,共14页
Fractionation of palm kernel oil (PKO) by short path distillation (SPD) at two feed flow rates (135 g/h and 195 g/h) and six distillation temperatures, TD,s (200, 210, 220, 230, 240 and 250 ℃) was investigate... Fractionation of palm kernel oil (PKO) by short path distillation (SPD) at two feed flow rates (135 g/h and 195 g/h) and six distillation temperatures, TD,s (200, 210, 220, 230, 240 and 250 ℃) was investigated. Other distillation parameters, such as vacuum pressure (0.001 mbar), blade rotation speed (400 rpm) and temperature of the feed material (60 ℃) were kept constant. The fractionated products, known as residue and distillate, were analysed for physico-chemical properties including fatty acid composition (FAC), triacylglycerol (TAG) composition, slip melting point (SMP), thermal analysis by differential scanning calorimetry (DSC) and solid fat content (SFC). Product yield was measured as well. Crystallisation behaviour of PKO and the fractionated products were studied by measurement of isothermal crystallisation, Tc,. at 0, 5, 10, 15, 20 and 25 ℃. The distillates, collected at all fractionation temperatures, were enriched with caprylic, capric and lauric acids. These fractions were also concentrated with low molecular weight and C36 TAGs. Distillates obtained at higher TDis (230-250 ℃) exhibited higher in SMP and SFC. On the other hand, the residual oils collected at all fractionation temperatures contained higher amount of long-chain fatty acid and palmitic acid. These fractions were enriched with high molecular weight TAGs. Residues obtained at lower Tois (200-220 ℃) were low in SMP and comparable SFC with PKO. Changes in fatty acid and TAG composition resulted in different crystallisation behaviour of the fractions. Distillates collected at all fractionation temperatures crystallised in a sharper peak while residues obtained at higher T Dis (230-250 ℃) showed broader crystallisation peaks, as shown by the DSC thermograms. 展开更多
关键词 Palm kernel oil short path distillation palm kernel distillates palm kernel residues crystallisation behaviours.
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