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1.
通过树脂的静态、动态实验研究,确定树脂吸附法分离提纯结晶废液中利巴韦林的优化工艺。选取LSD树脂吸附分离利巴韦林,上柱溶剂为90%乙醇水溶液,洗脱剂为pH8·5的Na2CO3溶液,该工艺使利巴韦林的浓度由不到10%浓缩到80%以上。再通过浓缩结晶可得到合格的利巴韦林产品。计算了吸附柱在不同流速下的总传质系数和传质区高度,为吸附器的设计提供了重要的数据。该工艺过程简单、无外添加、不使用有毒溶剂、能耗小。  相似文献   

2.
目的观察比较(干扰素+西咪替丁外用)[1]+利巴韦林与单用利巴韦林治疗小儿手足口病的疗效。方法将204例手足口病患儿随机分为治疗组104例,给予(干扰素+西咪替丁+0.9%生理盐水)外涂于口腔粘膜,舌头疱疹溃疡及皮肤皮疹+利巴韦林肌注或静脉用药。对照组100例,给予肌注或静脉滴入利巴韦林,每日1次。2组同时均给予对症支持治疗。结果治疗组的总有效率为94.7%,对照组为78%,2组比较差异有显著性(P<0.01),差异具有统计学意义,2组均未发现有副作用。结论干扰素+西咪替丁外用及利巴韦林治疗小儿手足口病均未见明显不良反应。干扰素+西咪替丁外用+利巴韦林治疗方案疗效较单用利巴韦林显著。症状改善见效快,住院时间缩短,疗效确切,值得临床推广。  相似文献   

3.
采用中国药典2015版四部通则0931第二法浆法,以磷酸缓冲液(p H为6. 8)、醋酸缓冲液(p H 4. 0)、盐酸溶液(p H 1. 2)和水等4种溶液为溶出介质,搅拌转速为50 rpm,比较已上市利巴韦林片、自制片与进口利巴韦林片在4种不同的溶出介质中的溶出曲线,为评价药品质量提供依据。结果表明:自制利巴韦林片在4种溶出介质中15 min溶出度与国内、国外两种市售利巴韦林片相当,均大于85%。  相似文献   

4.
大孔吸附树脂HZ816对红霉素的固定床吸附过程研究   总被引:1,自引:1,他引:0  
在上柱质量浓度为2.31—6.56 mg/mL、流量为14.33—42.80 mL/h的范围内研究了固定床吸附柱中大孔吸附树脂HZ816对红霉素的动态吸附过程,考察了原料液质量浓度和进口流量等操作参数对穿透曲线的影响。并采用基于液膜及孔内扩散模型的动力学模型,同时考虑吸附树脂颗粒内外扩散阻力及轴向扩散的影响,研究了固定床上红霉素在大孔吸附树脂中的吸附动力学,并从穿透曲线回归得到液膜传质系数孔内扩散系数。结果表明,在实验范围内,该模型能较好地描述红霉素在HZ816树脂上的吸附过程,由模型拟合得到的液膜传质系数随着原料液质量浓度减小而增大,随着流量升高而增大;孔内扩散系数随着原料液质量浓度增大而减小,随着流量升高而减小。为采用大孔吸附树脂HZ816吸附技术分离纯化红霉素工艺提供了实验和理论基础。  相似文献   

5.
色谱模型对研究色谱分离过程中的传质动力学具有重要的意义。根据物料守恒原理,结合传质扩散模型推导色谱分离连续方程。假设吸附过程相平衡是线性,连续性方程推导出理论板数与流速和色谱模型参数有关。在多组不同流速条件下测定色谱柱参数,计算得到两组分的传质系数和扩散系数。分别用测定模型参数模拟脉冲实验,结果表明拟合较好。  相似文献   

6.
利巴韦林生产废液处理的工艺研究   总被引:3,自引:0,他引:3  
通过树脂的静态、动态实验吸附和层析研究,确定利用离子交换树脂层析法分离提纯利巴韦林生产废液的最佳工艺。选LSD树脂为层析介质,料液溶剂为90%乙醇水溶液,用90%乙醇水溶液和纯水进行两阶逐次洗脱。该工艺使利巴韦林的浓度由不到10%浓缩到95%以上,分离效果较好,再通过浓缩结晶得到合格的利巴韦林产品。整个工艺过程简单、无外添加物,不使用有毒溶剂、能耗小。  相似文献   

7.
张林生  刘周明  李光耀  陈婷婷  薛冰 《化工学报》2019,70(11):4172-4180
在基于直接接触换热法的开式吸附热泵系统中,引入预吸附过程或预设传质通道,考察其对蒸汽生成和系统性能的影响。实验结果表明,预吸附蒸汽压力为0.0680 MPa(饱和温度=89.2℃),系统生成高温蒸汽的平均温度为203℃,系统整体温升为98.4℃,相对于无预吸附系统,生成蒸汽的时间和质量分别增加52.2%和27.0%,系统制热系数和制热功率分别提升28.2%和27.2%。预置树枝状传质通道后,生成蒸汽的时间和质量分别增加了17.8%和8.75%,系统制热系数和制热功率分别提升8.16%和9.05%。预吸附过程使吸附床较快达到整体吸附和热力平衡,缩短蒸汽到达床层出口的时间。预吸附压力越高,系统到达整体吸附平衡的用时越短,蒸汽生成时间越早。传质通道促进吸附床局部平衡的达成,减小局部传质阻力,使部分蒸汽可迅速到达出口。整体和局部吸附平衡的快速达成,均强化了蒸汽的动态生成过程,提升系统整体性能。  相似文献   

8.
建立了用LC/MS/MS测定动物源食品中利巴韦林药物残留方法。样品中加入内标,用1%三氯乙酸-乙腈(1∶1,V/V)溶液提取,用氨水调至碱性,经Agilent PBA固相萃取小柱净化,净化后溶液经色谱柱IntertsilHPLC HILIC column(3.0 mm×150 mm,5μm)进行分离,用乙腈和水作为流动相进行梯度洗脱,电喷雾正离子(ESI+)模式电离,多反应监测(MRM)模式进行检测。实验结果,利巴韦林在2.0~50.0 ng/m L范围内有很好的线性关系(r2≥0.995);方法的定量限为2.0μg/kg;在2.0、10.0、50.0μg/kg添加浓度水平回收率为87.5%~97.07%,相对标准偏差(n=6)在2.76%~3.43%之间。此方法灵敏、准确、方便,适合于动物源食品中利巴韦林残留通量分析。  相似文献   

9.
梯形波脉冲筛板萃取柱传质性能   总被引:1,自引:0,他引:1  
本文以UO_2(NO_3)_2—30%TBP(KO)为实验体系,进行了梯形波脉冲筛板柱传质性能的研究。实验中测量了两组分的两相稳态浓度剖面共13组,以扩散模型为基础,求得了梯形波脉冲柱的“真实”传质单元高度HTU_(ox),分散单元高度HDU及表观传质单元高度HTU_(oxp)。通过对实验结果进行分析,选择出了适于本实验体系的较好的操作条件。  相似文献   

10.
在太阳能吸附制冷循环解吸过程中传质性能受到非稳定热源温度的限制,而压力调节可作为强化传质的有效补偿手段。通过构建活性炭-甲醇工质对的恒温解吸理论模型给出了解吸率、解吸速率的表达式,对变压强化传质效果进行计算,揭示了温度与压力变化对解吸率的影响规律。计算结果显示系统压力降低10 kPa可等效于热源温度升高了6~8℃。搭建了以活性炭-甲醇为工质对的吸附单元管吸附制冷平台,实验结果显示当解吸温度分别为90、100和110℃时,系统压力降低14 kPa后,解吸率分别提高了20.5%、15.1%和12.1%,平均解吸速率分别提高了49.3%、44.6%和37.1%,与理论计算吻合较好。得出了温度与压力对解吸性能影响的耦合关系,并对实际太阳能吸附制冷系统变压解吸方法给出建议。  相似文献   

11.
地黄中梓醇的超声提取-树脂分离纯化工艺   总被引:2,自引:0,他引:2  
研究了地黄中梓醇的超声提取-树脂分离纯化工艺。结果表明,超声提取的最佳工艺条件为:提取溶剂采用68%(体积)的乙醇,液料体积(ml)质量(g)比5:1,超声时间36 min。考察了10种大孔树脂对地黄粗提液的分离纯化效果,其中以H103对梓醇的纯化效果最佳。通过实验进一步考察了H103的动态吸附性能,得到分离纯化的最佳工艺条件为:上柱液浓度为6.15 mg·ml-1,上柱液流速为1.0 ml·min-1,洗脱剂为75%乙醇,洗脱流速为0.5 ml·min-1,洗脱体积为3.33 BV(bed volume)。提取、纯化两步操作后梓醇纯度达到62.39%。  相似文献   

12.
Sulfate mass transfer coefficient (MTC) is a sensitive parameter to evaluate the kinetic leakage of anion exchange resin used in condensate polishing system of thermal and nuclear power plant. However, a sufficiently precise determination method has not been well established. In this paper, the final expression of sulfate MTC derived based on plug flow reactor model is the same as Harries’ model, which is widely acknowledged in this field. In the determining system we constructed, in-situ calibration of the concentration of sulfate and its cation conductivity was conducted and sulfate MTCs of four typical strongly basic anion exchange resin samples were determined. The systematic error is 8.26% and the calibrated curve used for quantifying sulfate is obtained. The repeatability and reproducibility standard deviation are 0.05×10-4 m·s-1 and 0.07×10-4 m·s-1 respectively, which are lower than previous works. By controlling test condition accurately, this study has developed a more precise sulfate MTC determining method. This method provides a basis for further research.  相似文献   

13.
以辣椒树脂为原料,采用静态吸附法确定了201×7型阴离子交换树脂吸附辣椒碱的最优工艺和提取机理。通过可见分光光度法测定了辣椒碱的质量浓度,并绘制出了不同pH的吸附等温线,建立了离子交换吸附辣椒碱的动力学模型。实验结果表明:该树脂吸附辣椒碱的最优pH值为5.5,当pH5.0或pH6.0时,Langmuir方程能够更好地拟合该吸附过程;而当pH=5.0~6.0时,辣椒碱的吸附等温线更符合Freundlich方程。在pH=5.5、308.15K下,较高的辣椒树脂的质量浓度能显著提高离子交换速率,且初期(t30 min)800~1200r/min的搅拌速率有利于吸附过程。通过计算得出,树脂吸附辣椒碱模型的速率常数k0=2.11×10-3s-1、活化能Ea=12.6 k J/mol、反应级数为0.268,并利用Freundlich模型解析获得了最优pH值(5.5)下阴离子交换树脂吸附辣椒碱的动力学方程。  相似文献   

14.
基于亲水/憎水复合膜的全热交换器换热换湿性能   总被引:2,自引:0,他引:2       下载免费PDF全文
张炎  张立志  项辉  徐学利 《化工学报》2007,58(2):294-298
膜全热交换器由于可以同时回收空调排风中的潜热和显热而受到重视。研究了基于PVAL/PVDF复合透湿膜的全热交换器的透热透湿性能,实验测定了新风与排风之间的显热交换能力和水蒸气交换能力,并建立了基于亲水/憎水复合膜的逆流膜全热交换器传热传质计算模型,实验与理论结果吻合较好。结果表明,该复合膜全热交换器的总传热系数为20~35 W·m-2·℃-1,总传质系数为(1.5~3.5)×10-3 m·s-1。  相似文献   

15.
The desorption process of volatile organic compounds(VOC) from a polymer adsorbent in counter-current multistage fluidized bed was studied. And a mathematical model considering the mass transfer dynamics was developed, which was validated from experiment data. The gaseous ethyl acetate mass transfer was discussed, and the limiting step is the intraparticle mass transfer of the desorption process. The value of intraparticle mass transfer coefficient is between 1.85 × 10~(-6) and 1.38 × 10~(-5) m·s~(-1) under temperature of 100–160 °C. Experiments under different operating conditions were carried out. The effects of operating conditions such as gas–solid flow ratio,gas inlet temperature and total stage number of multistage fluidized bed on outlet VOCs concentration and desorption efficiency were discussed. The maximum outlet VOCs concentration and corresponding desorption efficiency of the multistage fluidized bed desorber was calculated under different gas inlet temperatures and total stage numbers.  相似文献   

16.
《分离科学与技术》2012,47(3):512-532
Abstract

Ion exchange equilibria and kinetics are determined for lysine adsorption on the strong acid cation exchanger DIAION SK‐1B at temperatures of 25, 40, and 60°C. The ion exchange equilibrium is found to be independent of temperature. Conversely, the kinetics of ion exchange increases dramatically as the temperature is increased. Average ion exchange selectivity coefficients of 6.0 g/cm3 and 0.52 are obtained for the ion exchange of divalent and monovalent cationic lysine with hydrogen ion, respectively. Resin phase diffusivities are determined by fitting batch binary ion‐exchange data with a mass transfer model based on the Nernst‐Planck equations. As the temperature is increased from 25 to 60°C, the resin phase diffusivity increases from 0.04×10?6 to 0.14×10?6 cm2/s for divalent lysine and from 0.16×10?6 to 0.55×10?6 cm2/s for monovalent lysine. The combination of temperature‐independent ion exchange equilibria and faster mass transfer at higher temperatures results in higher dynamic binding capacity and more efficient desorption of lysine when ion exchange is operated at an elevated temperature. This behavior is confirmed by means of column adsorption/desorption experiments whose results are found to be in agreement with a model incorporating the equilibrium and mass transfer data obtained in this work.  相似文献   

17.
李广军  杨英珍 《化工学报》1997,48(6):740-745
<正>气液两相流中界面波的存在对传热、传质、阻力特性及稳定性都有很大影响。前人有关界面波的研究大多偏重于两相流中界面波的类型及其转变,而对其特征参数变化规律(如振幅、波长、频率和速度等)的研究则很少。但界面波对气液两相流流动阻力和流动结构影响机理的深入研究必须以了解界面波的各特性参数为前提,同时界面波有关特性参数的深入研究也可为气液两相流的数学理论化提供实验基础。 本文以气、水为工质,系统研究了水平矩形管内气液两相流的界面波特性。根据界面波在时域、幅域内的不同特征区别出了各种类型的波并给出了相应的波形和流型图。着重研究了界面波各特征量随气液两相流量变化的变化规律。  相似文献   

18.
谢远红 《广东化工》2012,39(5):30-31
研究6种大孔吸附树脂对芹菜黄酮类物质的吸附和解吸性能,筛选出吸附率较高的XAD-16树脂,并对XAD-16树脂静态吸附和动态吸附解吸工艺做了研究。优化出XAD-16树脂纯化芹菜黄酮的最佳工艺参数为:室温下吸附;上样流速4 BV/h,在上样浓度0.55 mg/mL下,上样体积为15倍柱床体积;洗脱溶剂采用体积分数50%的乙醇,洗脱流速为6 BV/h,洗脱液量为4倍柱床体积。  相似文献   

19.
In this study, we investigated the performance of a synthetic resin for the adsorption of Li from pre-desilicated solution which is the waste liquid produced by extracting aluminum from fly ash. The adsorption kinetics and isotherms of the resin were obtained and analyzed. The saturated adsorption sites of the resin were in agreement with the quasi-second-order kinetic model. Then, the pore diffusion model (PDM) was applied to represent the lithium adsorption kinetics which confirming that the external mass is the limiting step. Moreover, we evaluated the adsorption properties of this resin in fixed-bed mode. We established a feasible extraction process for Li from strong alkaline solutions with low Li concentrations. The process parameters, such as the flow rate, initial adsorption solution concentration, water washing process, desorption agent concentration, and flow rate were studied. The desorption rate of the Li+ ions was directly proportional with the concentration of the desorption agent. The time required to accumulate Li decreased as the hydrochloric acid concentration and flow rate increased. Time of the peak appeared increased from 0.5 bed volume (BV) to 2.5 BV as the concentration was increased from 1 to 3 mol·L-1, and the peak increased from 231 to 394 mg·L-1. The resin presented good selectivity for Li+ ions and could effectively separate impurity ions from the pre-desilication solution.  相似文献   

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