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<正>变压吸附脱碳从变换气中脱除二氧化碳,氢收率可达99.5%,氮收率可达96%~99%,一氧化碳收率可达95%~98%,还可同时获得纯度大于98.5%(体积分数)的二氧化碳,2005年该项目被列为四川省重点科研项目。变压吸附提氢氢纯度99.9%(体积分数)时,氢收率可达95%~98%,氢纯度99.99%(体积分数)时,氢收率可达90%~95%,2002年该项目被列为四川省重点科研项目。变压吸附提纯与生产食品级或工业级二氧化碳变压吸附提纯一氧化碳变压吸附空分制氧提供XHK集散型造气微机油压控制系统,用户遍及全国各地。     

间甲氧基苯乙腈合成工艺研究

间甲氧基苯乙腈,别名3-甲氧基苯乙腈,主要用于医药、农药中间体。下游产品为间甲氧基苯乙酸乙酯,6-甲氧基-1,2,3,4-四氢异喹啉盐酸盐,6-甲氧基-1,2,3,4-四氢异喹啉盐酸盐为医药中间体,在医药行业应用较多。本文成功的合成间甲氧基苯乙腈,探讨了各反应条件对产品质量和收率的影响,产品纯度和总收率分别在99%(GC)和97%以上。     

水杨酸新戊二酯的合成

以水杨酸、氯化亚砜为原料,无水吡啶为催化剂,先制得水杨酰氯,再与新戊二醇在催化剂NaHSO4作用下合成了水杨酸新戊二酯,产品收率可达到89%以上,产品纯度97.6%。所得产物经GC-MS、核磁氢谱表征确认了其结构。     

芝麻酚的合成工艺改进

以胡椒环为原料,经傅克酰基化、 Bayer-Villiger氧化、水解3步反应合成了芝麻酚,总收率77.6%,产品纯度99.0%以上。其结构经熔点、核磁共振氢谱(1H NMR)确证。该方法工艺操作简单、反应温和,适合工业化生产。     

硝酸铈铵催化"一锅法"合成3,4-二氢嘧啶-2-酮

以硝酸铈铵为催化剂、无水乙醇为溶剂,醛、β-二羰基化合物(乙酰乙酸乙酯、乙酰乙酸甲酯、戊二酮)和脲在回流温度下进行环化缩合.考察了反应条件对产品收率的影响,并在较优反应条件下,合成一系列3,4-二氢嘧啶-2-酮衍生物,产品收率在80.0%以上,反应时间短,产品纯度高,操作简便,改进了Biginelli合成法.     

驱蚊剂N,N-二乙基间甲基苯甲酰胺的合成研究

以间甲基苯甲酸、二乙胺为原料,采用高温常压条件一步反应合成了N,N-二乙基间甲基苯甲酰胺(DEET)。用红外光谱、核磁共振氢谱对产物进行了表征。分析和讨论了原料间甲基苯甲酸与乙二胺配比、催化剂种类、催化剂用量、反应温度对产物收率的影响,得出了最优条件。在该条件下,DEET的产品纯度可以达到99%以上,收率71.5%。     

精密精馏分离光学异戊醇研究

采用高效填料 ,对预处理后的杂醇油进行两次精密精馏 ,获得异戊醇产品纯度 98% (质量 ) ,总收率95.0 % (质量 ) ;光学异戊醇产品纯度 95% (质量 ) ,收率 85.0 % (质量 )以上。     

4,4'-二羟基-3,3'-二硝基二苯甲酮的合成

以氯苯和对氯苯甲酰氯为原料,经傅克酰基化、混酸硝化、混合溶剂碱性水解3步反应制备4,4’-二羟基-3,3’-二硝基二苯甲酮,总收率78.34%。通过红外光谱、质谱、氢谱以及高效液相色谱对产品进行表征。采用单因素实验法对水解反应工艺进行考察,确定了最佳工艺条件。在该条件下粗水解产物收率为96.71%,纯度为97.11%。用DMF和异丙醇对水解产物进行重结晶,重结晶后产品收率为81%,纯度为99.30%。     

4,4'-二羟基-3,3'-二硝基二苯甲酮的合成

以氯苯和对氯苯甲酰氯为原料,经傅克酰基化、混酸硝化、混合溶剂碱性水解3步反应制备4,4'-二羟基-3,3'-二硝基二苯甲酮,总收率78.34%。通过红外光谱、质谱、氢谱以及高效液相色谱对产品进行表征。采用单因素实验法对水解反应工艺进行考察,确定了最佳工艺条件。在该条件下粗水解产物收率为96.71%,纯度为97.11%。用DMF和异丙醇对水解产物进行重结晶,重结晶后产品收率为81%,纯度为99.30%。     

氨基甲磺酸的高效简便合成

本文以甲醛、氨水和二氧化硫为原料,采用"一锅法"合成氨基甲磺酸,产品收率达到85%以上,纯度达到99%以上。该工艺具有操作简单、合成收率高、产品纯度高等特点,具有较好的应用前景。     

变压吸附─低温分离联合法制氢技术的应用

介绍了采用变压吸附─低温分离联合法从合成氨弛放气制取氢气的工艺流程及特点，制得氢气纯度＞99．9％，回收率可提高到95％以上，纯氢产量约为313、8m3／h。     

氯碱厂副产氢气的分离提纯方法

从纯化机制入手,介绍了氯碱厂的副产氢气经分离提纯到99．9％及99．9999％以上的方法：低温吸附法、变压吸附法和膜分离法等。     

高纯过氧化氢生产中有机物杂质的净化技术进展

介绍了工业级过氧化氢中有机物杂质的来源,综述了高纯过氧化氢生产中有机物杂质的净化技术研究进展,包括精馏、吸附、离子交换树脂、溶剂萃取、结晶、膜分离技术以及这些技术的组合净化技术。精馏净化产品纯度不高,但技术成熟,可工业放大;膜分离净化技术较安全,但膜的寿命短;吸附树脂工艺简单、净化效率高,但树脂易被氧化。指出以精馏为前净化技术,再与膜分离、树脂吸附相结合是有机碳杂质去除技术的发展趋势。     

VPSA技术在干气回收氢气的应用

回收氢气装置是利用经过脱硫处理后的芳烃厂富氢干气,采用国内成熟的变压吸附专利技术回收干干气气中氢气。利用高压吸附,低压抽真空解吸的原理,从含粗氢的干气中提纯出99.9%(v)的产品氢,提供芳烃装置用氢。同时变压吸附的尾气通过尾气压缩机增压后供芳烃装置做加热炉燃料,从而达到厂内富氢干气综合利用的目的,提高装置综合经济效益。     

变压吸附提氢工艺的优化

结合某甲醇厂甲醇尾气提氢技术指标，介绍了变压吸附装置的工艺原理；简述了8—1—6VPSA提氢装置工艺流程、工艺控制点以及自主开发的智能化PLC控制程序在提氢装置的应用情况；提出了提氢工艺的优化措施。结果表明，提氢装置可将氢气纯度提高到99．99％。     

A parametric study of layered bed PSA for hydrogen purification

The production of high purity hydrogen (99.99+%) at reduced cost is an important and sought target. This work is focused on the separation of hydrogen from a five component mixture (H₂/CO₂/CH₄/CO/N₂) by pressure swing adsorption. A complete mathematical model that describes the dynamic behaviour of a PSA unit is presented. This model is applied in the study of the behaviour of both single column and four columns PSA processes with layered activated carbon/zeolite beds and with an eight steps cycle. In the single column simulation, a 99.9994% purity hydrogen stream is attained at the end of the feed step for a process hydrogen recovery of 51.84% and a productivity of . The multicolumn simulation predicts a hydrogen recovery and purity, respectively, of 52.11% and 99.9958%. The influence of feed flow rate, purge to feed ratio and lengths of both adsorbent layers on the system performance is assessed. It is shown that the introduction of the zeolite layer improves both the purity and recovery of the process. Reduced models are formulated based on the sequential identification of controlling resistances in the complete model. The predictions of the reduced models are evaluated by comparing their results with those obtained from the complete model. It is shown that the model that merely takes into account the micropore resistance (described by the LDF model) and assumes thermal equilibrium only between the gas and solid phases satisfactorily predicts the behaviour of the pressure swing adsorption unit.     

Hydrogen recovery from Tehran refinery off-gas using pressure swing adsorption, gas absorption and membrane separation technologies: Simulation and economic evaluation

Hydrogen recovery from Tehran refinery off-gas was studied using simulation of PSA (pressure swing adsorption), gas absorption processes and modeling as well as simulation of polymeric membrane process. Simulation of PSA process resulted in a product with purity of 0.994 and recovery of 0.789. In this process, mole fraction profiles of all components along the adsorption bed were investigated. Furthermore, the effect of adsorption pressure on hydrogen recovery and purity was examined. By simulation of one-stage membrane process using co-current model, a hydrogen purity of 0.983 and recovery of 0.95 were obtained for stage cut of 0.7. Also, flow rates and mole fractions were investigated both in permeate and retentate. Then, effects of pressure ratio and membrane area on product purity and recovery were studied. In the simulation of the gas absorption process, gasoline was used as a solvent and product with hydrogen purity of 0.95 and recovery of 0.942 was obtained. Also, the effects of solvent flow rate, absorption temperature, and pressure on product purity and recovery were studied. Finally, these three processes were compared economically. The results showed that the PSA process with total cost of US$ 1.29 per 1 kg recovered H₂ is more economical than the other two processes (feed flow rate of 115.99 kmol/h with H₂ purity of 72.4 mol%).     

Modelling and simulation of two-bed PSA process for separating H_2 from methane steam reforming

Methane steam reforming is the main hydrogen production method in the industry. The product of methane steam reforming contains H_2, CH_4, CO and CO_2 and is then purified by pressure swing adsorption(PSA) technology. In this study, a layered two-bed PSA process was designed theoretically to purify H_2 from methane steam reforming off gas. The effects of adsorption pressure, adsorption time and purgeto-feed ratio(P/F ratio) on process performance were investigated to design a PSA process with more than99.95% purity and 80% recovery. Since the feed composition of the PSA process changes with the upstream process, the effect of the feed composition on the process performance was discussed as well.The result showed that the increase of CH_4 concentration, which was the weakest adsorbate, would have a negative impact on product purity.     

超纯过氧化氢制备中有机杂质的吸附净化技术进展

介绍了超纯过氧化氢的应用及其生产技术。论述了活性炭的吸附净化机理、工业过氧化氢中有机杂质的产生、危害以及常用的净化除杂技术。在对各种净化技术的优势和不足进行比较的基础上,指出吸附净化技术工艺简单、净化效果好。同时指出了采用活性炭吸附净化技术脱除工业过氧化氢中有机杂质的关键及存在的技术难点。     

丙烷脱氢反应气分离提纯丙烯和氢气过程严格模拟与能效评估

丙烷脱氢(PDH)是生产丙烯产品的重要方式之一,丙烷脱氢反应气组分复杂,为获得聚合级丙烯和纯度不小于99.90 mol/mol的氢气产品,在Aspen软件中对丙烷脱氢反应气分离和富氢尾气回收氢气的过程进行建模和模拟,分离过程包括醇胺脱碳、压缩深冷、脱乙烷、丙烯精馏和变压吸附单元。为了合理利用丙烯精馏塔的能量,对丙烯精馏塔进行能量集成,采用变压吸附工艺回收氢气并对分离过程工艺参数进行灵敏度分析及优化工艺参数,以提高经济性和能效。模拟结果可得到符合要求的丙烯和氢气产品,单位产品能耗分别为267.46 kg标准油/t丙烯产品,474.44 kg标准油/t氢气产品。