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1.
以质量比为1∶9∶20的硝酸铈铵、高岭土和SnCl4·5H2O制备了高岭土复合型固体酸催化剂,制备条件为70℃水浴中陈化12h,促进剂H2SO4浓度为2.0mol/L,浸渍12h,350℃焙烧3h,并采用XRD对催化剂进行了表征。该催化剂用于异丁酸与正丁醇的酯化反应合成了异丁酸丁酯,考察了带水剂种类、催化剂用量、异丁酸与正丁醇的摩尔比、反应时间及催化剂重复使用性等因素对酯收率的影响。结果表明,该催化剂具有催化活性高、易分离回收、成本低、重复使用性好等优点。适宜反应条件为醇酸摩尔比为1.7、催化剂用量为反应物总质量的2.0%、反应时间100min,酯收率为96.5%。该催化剂重复使用6次,其酯收率仍接近80%。  相似文献   

2.
安卫红  卢晓明 《煤炭与化工》2021,44(10):135-137
为了寻找一种高效的古龙酸甲酯合成工艺,助推维生素C (VC)原料生产行业实现节能减排及绿色发展.以2-酮基-L-古龙酸、甲醇为原科,浓硫酸为催化剂,在微通道反应器中合成古龙酸甲酯.考察了物料比、催化剂加量、反应温度及停留时间等因素对产品含量和转化率的影响,优化了工艺参数.实验结果表明,当反应温度为85℃时,催化剂浓硫酸的用量可减少至0.2%,反应时间可缩短至90 min;与传统釜式合成工艺相比,新工艺减少了催化剂用量,消除了过程反应放大效应和温度波动,缩短了反应时间,可提高工艺安全性.  相似文献   

3.
以高岭土为载体、磷钨酸( PW12)为活性组分制备了非均相酯化催化剂PW12/高岭土,将其用于异丁酸与正丁醇的催化酯化合成异丁酸丁酯,考察了高岭土以及催化剂的焙烧温度、焙烧时间和磷钨酸与高岭土的质量比等因素对异丁酸丁酯酯化率的影响,并采用FTIR技术对载体、活性组分及催化剂进行了表征.结果表明,催化剂适宜的制备条件为:...  相似文献   

4.
范德滨 《同煤科技》2016,(4):17-19,24
实验主要研究了以磷钨酸/TiO_2催化剂,30%的双氧水为氧化剂时,柴油脱硫反应的脱硫率与反应的时间、反应温度、反应催化剂用量等反应条件的关系。  相似文献   

5.
采用单因素分析法考察自制油酸正丁酯硫酸酯钠盐(AH)表面活化处理重质碳酸钙的最佳工艺条件,通过控制分散剂十二烷基苯磺酸钠(SDBS)的用量、反应时间、反应温度、活化剂油酸正丁酯硫酸酯钠盐的用量,得到AH改性重质碳酸钙的最优化工艺条件为:m(SDBS)∶m(CaCO3)=2%,m(AH)∶m(CaCO3)=2%,活化时间35min,活化温度50~55℃。在此条件下,改性碳酸钙的沉降体积为0.76mL/g,吸油值为17.9mL/100g,粘度为140mPa.s,pH值为7.95。  相似文献   

6.
通过单因素实验分别考察了硫酸锰等四种金属离子催化剂与硝酸铵等三种铵盐的不同组合对合成反应的影响,选出硫酸锰和硝酸铵作为合成葡萄糖三聚氰胺树脂催化剂.通过正交试验法对合成反应体系的pH、反应温度、催化剂用量、原料配比、反应时间及固化条件进行了优化.实验结果表明,最佳的合成条件为:葡萄糖与三聚氰胺的摩尔比为3.0:1、催化剂用量为0.3 g、反应温度为106 ℃、反应时间为6 h.用邻苯二甲酸酐作固化剂,固化效果较好.较优的固化条件为:固化剂用量为胶粘剂质量的15%、固化时间为1.5 h、固化温度为120 ℃.  相似文献   

7.
粉煤灰复合硫酸亚铁固体酸催化剂的制备及表征   总被引:1,自引:0,他引:1  
利用沉淀-浸渍法,以工业废物粉煤灰和硫酸亚铁为主要原料制备FSZ类固体酸催化剂,应用在酯化反应中具有良好的催化效果。并用X衍射仪、红外光谱仪和比表面仪等仪器FSZ型催化剂进行表征,结果表明在主要成分的配比为:硫酸亚铁∶氧氯化锆∶粉煤灰=2∶1∶4(质量比),0.5 mol/L硫酸溶液浸泡,在550℃下焙烧3h所制得的催化剂,用于合成中酯化率可达92.9%。  相似文献   

8.
乏风瓦斯催化燃烧实验研究   总被引:1,自引:0,他引:1  
制备了含有稀土元素涂层的铂、钯贵金属堇青石载体催化剂,用低浓度甲烷对该催化剂进行催化燃烧实验,研究了不同反应温度、不同甲烷体积分数、不同反应空速下甲烷的转化率。实验结果表明:在反应空速为30 000 h-1条件下,温度为450℃时,甲烷转化率为68%左右,达到催化剂的起燃温度;在700℃时,甲烷转化率达到100%。甲烷体积分数为0.2%~1.5%时,甲烷转化率都超过了99%,该催化剂适用于乏风瓦斯催化燃烧。  相似文献   

9.
通过溶液浸渍法成功制备粉煤灰负载Fe2+/Cu2+催化剂,利用XRD、XRF和FTIR等对组成和结构进行表征,研究pH值、反应温度、H2O2质量浓度及催化剂用量等对甲基橙降解效果的影响。结果表明:粉煤灰负载型催化剂的活性组分由粉煤灰本身所含铁,以及浸渍过程中吸附和表面残留的铜、亚铁离子组成。负载型催化剂对甲基橙降解具有较宽的pH值范围,良好的降解效果,对于1 g/L的甲基橙溶液,当催化剂用量为1 g/L,pH值为4,反应温度为50℃,H2O2质量浓度为33.3 g/L,搅拌时间为20 min,甲基橙的降解率接近100%。  相似文献   

10.
以Hβ沸石分子筛为催化剂,对苯甲醚与三氯乙醛的Friedel-Crafts羟烷基化反应进行了研究,并系统地考察了反应时间、反应温度、催化剂用量对催化活性的影响,确定的最佳反应条件:反应时间为8 h,反应温度为70℃,催化剂用量为3.0 g。在此条件下,苯甲醚的转化率达到了45.0%,4-甲氧基-α-三氯甲基苯甲醇的选择性达到了94.0%。  相似文献   

11.
<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH  相似文献   

12.
正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to  相似文献   

13.
<正>Developing ecological lighting source The world is facing the big problem of energy shortage today and the contradiction between economy development and environmental protection is worsened.Therefore,people are more likely to choose an ecological light source that is more energy efficient and environmental friendly.The choice provides great opportunity for the development of rare earth optical material industry in China.The concept of green lighting positions rare earth luminescent material as a leading player in illumination market.The light source of both rare earth luminescent lamp and LED lamp is ecological and energy saving.This is why  相似文献   

14.
正Galaxy Magnet announced its financial results for the first half of 2014 on August 14.For the first six months ended on 30 June 2014,Galaxy Magnet achieved operation income of RMB 182.3 million,up8.40% over the same period of 2013,and the net profit attributable to the shareholders of the listed company of 34.02 million yuan,increasing 35.49% over the same period of last year.Stable performance increase was led by development of new customers and application market of magnets.  相似文献   

15.
<正>China has rich rare earth resources.Output of rare earth and steel in China ranks the top first in the world.However,there is still certain distance between the steel produced in China and developed countries from the point of varieties and quality.China still has to import some types of steel.Improving the quality should be emphasiZed in future development of steel industry in China.Rare earth can be used to upgrade traditional steel  相似文献   

16.
正November 21~30,2014Due to weak demand from downstream industries,transactions of rare earth in Chinese domestic market were inactive.It was difficult to sell any rare earth products except for dysprosium oxide and terbium oxide.Suppliers lost confidence in recent market.Demand for rare earth products was soft.Consumers continued to take a wait-and-see attitude.Rare earth export market remained slow.  相似文献   

17.
分析了近年来国内外稀散金属产业的生产、应用、资源与市场状况.铟锡氧化物靶材、砷化镓晶片、锗红外材料、铼高温合金和硒在电解锰及玻璃的应用等已成为稀散金属的主要应用领域.稀散金属的产量快速增长达到历史高位而导致了市场的失衡.以GaInP_2/GaAs/Ge,CIGS和CdTe为代表的非硅系太阳能电池是稀散金属的新兴应用领域,将给稀散金属带来日益增长的需求.  相似文献   

18.
<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth  相似文献   

19.
正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products  相似文献   

20.
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