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41.
铜浸出液的净化除铁研究 总被引:1,自引:0,他引:1
研究了氧化-中和沉淀法从铜浸出液中除铁的工艺条件,并介绍了工业实践。 相似文献
42.
Slow growth and high seedling mortality limit direct seeding establishment of guayule (Parthenium argentatum G.). This study was conducted to assess seedling growth enhancement by the addition of different rates and forms of N fertilizers and Ca salts. Experiments were conducted in a greenhouse with cultivar 593 under both surface and subirrigated conditions using water low in salts (salinity of 0.8 dSm–1, SAR of 5.0 and 10 mg Ca L–1). Under surface-irrigated conditions, seedling height and fresh plant weight increased with N application to the irrigation water to 70 mg L–1. The best seedling growth was observed when (NH4)2SO4 was added in combination with CaCl2 or CaSO4. Progressively less growth was observed by addition of (NH4)2SO4 alone, CO(NH2)2 plus CaSO4, CO(NH2)2 alone and Ca(NO3)2. When seedlings were subirrigated, however, the best growth was observed with Ca(NO3)2. Intermediate growth was obtained with (NH4)2SO4 plus CaSO4 and lowest growth rates with (NH4)2SO4 alone. These differential responses may be explained by the differences in leaching and volatile characteristics of the N forms. Growth enhancement from N and Ca additions increased with time with significant increases 45 days after seeding. Nitrogen application with Ca may be effective amendment in promoting subsequent growth of direct seeded guayule. 相似文献
43.
Characterization of nanoporous materials prepared from montmorillonite clay and its application to the decolorization of mare's milk oil 总被引:1,自引:0,他引:1
J. Temuujin M. Senna Ts. Jadambaa D. Burmaa Sh. Erdenechimeg J. Amarsanaa G. Burmaa 《Journal of Porous Materials》2006,13(1):49-53
Nanoporous materials have been prepared by leaching the purified montmorillonite clay with sulfuric acid (H2SO4) solution with varying concentrations (0.5–2 M) at 80°C for 0.5–4 h. Acid leaching causes partial amorphisation of the clay
with depletion of MgO, Al2O3, CaO and Fe2O3 components mostly from interlayer and octahedral sites. This increases the specific surface area by more than 3 times, i.e.
from 49.1 to 157 m2/g. The pore-size distribution curves calculated from the adsorption isotherms of the leached montmorillonite show that most
of the pores are in the mesoporous region with their diameter ranging 3–4 nm. This material turns out to be appropriate for
bleaching of the mare's milk oil. The chemical and structural changes of the acid-leached montmorillonite are discussed in
terms of the decolorization capacity. 相似文献
44.
从煤矸石制取氯化铝联产橡胶填料的研究 总被引:1,自引:0,他引:1
在实验室小试、中试装置上进行了从煤矸石制取氯化铝联产橡胶填料的研究,考察了煤矸石性质、工艺条件等对产品质量的影响,结果发现最佳工艺参数为焙烧温度600~q00℃.焙烧时间为15~90min.焙烧温度对产品质量影响更为显著,制得结晶氯化铝产品质量达到合格品标准,填料用作橡胶制品填充剂具有较好补强与抗曲性能,其胶片的物理机械性能达到普通橡胶板标准。 相似文献
45.
探讨了磷酸体系下不同因素对废旧锂电池正极材料中有价金属浸出效率的影响,结果表明:在浸出时间60min,反应温度60℃,磷酸浓度2mol/L,液固比20mL/g,还原剂(H2O2)体积分数为4%时,可得最佳浸出效果,Co、Li、Mn、Ni浸出效率分别可达96.3%、100%、98.8%和99.5%;浸出液添加相应比例金属离子,采用草酸共沉淀法制备前体材料(Ni1/3Co1/3Mn1/3)C2O4,并得到相应再生磷酸溶液。再生磷酸进行循环浸出实验,实验研究结果表明:循环浸出5次之后Li的浸出率仍可保持在90.1%,而Co、Mn和Ni的浸出率在75.0%以上。前体添加锂源Li2CO3煅烧合成Li(Ni1/3Co1/3Mn1/3)O2材料,考察了不同温度对Li(Ni1/3Co1/3Mn1/3)O2材料合成的影响,结果显示,当合成温度为800℃时,得到的材料性能最优良,初次放电容量可达136.4mA·h/g。在0.2C下经过50圈循环后容量保持率为97.2%。 相似文献
46.
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. 相似文献
47.
48.
49.
The effects of surfactant on the solvent extraction in leaching sphalerite were investigated. It is found that sodium dodecyl sulfonate is the effective surfactant in improving the zinc recovery from sphalerite in the aqueous FeCl3-HCl-tetrachloroethylene system. Through the measurements of surface tension and viscosity of the sphalerite slurry modified with different surfactants, it is concluded that sodium dodecyl sulfonate in the concentration range of 0.05 to 0.2g L-1 can improve the viscosity of sphalerite slurry in the water, decrease the surface tension of leaching solution, prevent the aggregation of ore particles, and give very high zinc extraction . 相似文献
50.
渗漏溶蚀作用下碾压混凝土层(缝)面抗剪强度衰减规律试验研究 总被引:5,自引:4,他引:1
采用硝酸铵溶液循环浸泡的方式加速并模拟碾压混凝土层(缝)间渗漏溶蚀过程,应用直剪法测试抗剪强度,研究了溶蚀对混凝土层(缝)面抗剪强度的影响。结果表明,碾压混凝土层(缝)间渗漏溶蚀沿着缝面的法向逐渐向两侧混凝土的内部延伸,缝面溶蚀深度,即溶蚀前锋线至缝面的距离,用酚酞指示剂+电子探针线扫描技术测定,与钙离子累计溶出量呈线性关系,可以定量表征溶蚀程度。渗漏溶蚀引起缝隙两侧混凝土的孔隙率增大,微观结构变差,混凝土层(缝)面摩擦系数、黏聚力下降,但下降速率逐渐降低,衰减规律遵循牛顿冷却定律。试验数据拟合表明,基于牛顿冷却定律建立的以缝面溶蚀深度为自变量的抗剪强度衰减模型能够很好地反映碾压混凝土层(缝)面抗剪强度变化规律。 相似文献