高纯度金丝桃素生产工艺研究

利用大孔吸附树脂吸附法研究了金丝桃素的提取分离方法.结果表明,采用HZ 816大孔吸附树脂对贯叶连翘粗提物进行吸附纯化,以水、40%乙醇、60%乙醇洗去大量杂质后,以80%乙醇解吸,所得样品再经酸水结晶可得高纯度的金丝桃素.该方法简便,消耗低,产品纯度高,回收率高.     

无花果叶中补骨脂素的分离纯化工艺研究

研究了大孔树脂分离纯化无花果叶中补骨脂素的工艺条件及树脂前处理的方法。以补骨脂素洗脱率和纯度为考察指标,确定DM101型大孔吸附树脂分离纯化补骨脂素的吸附性能和洗脱参数,建立用紫外分光光度法进行大孔树脂前处理的方法。结果表明,DM101型大孔吸附树脂吸附容量以干树脂计为9.76mg·g~(-1),用纯化水和不同浓度的乙醇依次洗脱,以60%乙醇洗脱效果最佳,洗脱率达90.76%,总干燥物中补骨脂素含量达69.28%。大孔吸附树脂对补骨脂素有较好的分离纯化作用,且工艺简单,成本低,易于工业化生产。     

大孔吸附树脂分离纯化番石榴叶总皂苷的工艺研究

研究大孔吸附树脂分离纯化番石榴叶总皂苷的工艺条件.番石榴叶用70%乙醇回流提取后,上D101型大孔树脂,水洗后分别用30%,50%,70%乙醇洗脱,以番石榴叶总皂苷的洗脱率为指标,考察大孔树脂分离纯化番石榴叶总皂苷的吸附性能和洗脱参数.番石榴叶总皂苷主要富集于30%、50%乙醇洗脱液部分,大孔吸附树脂的吸附容量为17.53 mg·g-1,洗脱率达70.42%,而50%乙醇洗脱时总皂苷纯度可达55.68%,优选洗脱条件为用水洗去水溶性杂质,50%乙醇洗脱总皂苷.     

黄龙胆根黄酮类化合物的提取、纯化工艺研究

通过单因素与正交实验研究了微波辅助乙醇溶剂法提取黄龙胆根黄酮类化合物的最佳工艺条件,优化了大孔树脂对所得黄酮类化合物进行纯化的工艺。得出提取最佳工艺条件为:微波功率300 W,微波时间8 min,乙醇浓度35%,料液比1∶20。在此条件下,得率为32.19%,粗提物总黄酮含量为1.97%。通过静态实验,选出最佳纯化树脂为AB-8大孔树脂;通过动态实验,得出吸附分离黄龙胆根黄酮类化合物工艺参数为:上样液流速2.00 m L/min,洗脱剂流速2.00 m L/min。经纯化后总黄酮含量为20.17%。     

大孔树脂对5-羟基色氨酸的吸附研究

筛选适合分离纯化加纳籽中5-羟基色氨酸的树脂,并确定最佳工艺。以5-羟基色氨吸附量和回收率为指标,制定吸附等温线和研究树脂静态吸附动力学,确定大孔树脂型号;动态吸附分离法确定分离条件。对6种树脂进行考察,其中AB-8型大孔吸附树脂对5-羟基色氨酸具有良好的吸附分离性能,其初步分离纯化工艺条件：以浓度10.5mg/mL的样品动态吸附,以50%的乙醇为解吸剂,洗脱流速1.5BV/h,回收率98.79%。结果表明,AB-8型大孔吸附树脂适合分离纯化5-羟基色氨酸,该方法操作简便,利于实际的生产。     

大孔吸附树脂分离纯化银杏叶总黄酮的研究

利用4种大孔吸附树脂分离纯化银杏叶总黄酮.结果表明,HPD100型大孔吸附树脂最适合分离纯化银杏叶总黄酮,该树脂的静态饱和吸附量(以干树脂计)为63.8 mg·g-1,静态洗脱率为91.2%,动态饱和吸附-洗脱量为14.0 mg·g-1,洗脱剂为70%乙醇,洗脱剂用量为4倍树脂体积,树脂可重复使用7个周期.     

无花果多糖脱色工艺研究

采用大孔吸附树脂优化无花果多糖的脱色工艺。以无花果干果为原料,热水浸提得无花果多糖粗提物,经Sevage试剂去蛋白、乙醇沉淀后冻干得粗多糖粉末。以脱色率和多糖保留率为考察指标,筛选适合无花果多糖脱色的最优树脂和最佳的脱色工艺条件。结果表明,无花果多糖脱色的最优树脂为LSD-296,最佳脱色工艺条件为:树脂用量2.0g、多糖溶液浓度4 mg·mL~(-1)、pH值6、脱色温度40℃,为无花果多糖进一步分离纯化奠定了基础。     

大孔树脂分离纯化沙芥黄酮的工艺研究

用大孔吸附树脂分离纯化沙芥总黄酮,比较了7种大孔树脂对沙芥总黄酮的静态吸附动力学特性,优选出D-4020型大孔吸附树脂分离纯化沙芥总黄酮,并对其进行动态吸附实验。结果表明,D-4020纯化沙芥总黄酮的最佳工艺参数为:上样液浓度0.4 mg/mL,pH值5,上样流速2 mL/min;使用4BV用量95%的乙醇作为洗脱剂,洗脱流速为2 mL/min。采用该工艺分离纯化沙芥总黄酮含量达40.91%。     

大孔树脂分离纯化沙芥黄酮的工艺研究

用大孔吸附树脂分离纯化沙芥总黄酮,比较了7种大孔树脂对沙芥总黄酮的静态吸附动力学特性,优选出D-4020型大孔吸附树脂分离纯化沙芥总黄酮,并对其进行动态吸附实验。结果表明,D-4020纯化沙芥总黄酮的最佳工艺参数为：上样液浓度0.4 mg/mL,pH值5,上样流速2 mL/min;使用4BV用量95%的乙醇作为洗脱剂,洗脱流速为2 mL/min。采用该工艺分离纯化沙芥总黄酮含量达40.91%。     

地黄有效成分梓醇的分离纯化工艺研究

用大孔树脂分离纯化地黄提取物中有效成分梓醇,考察了4种不同极性大孔吸附树脂对梓醇的吸附和解吸附性能,筛选出最佳树脂AB-8进行分离实验,考察最佳上样量、吸附时间以及洗脱溶剂。结果表明,地黄提取物中梓醇的分离纯化最佳工艺条件是:上样量171 mg/g树脂,吸附时间为0. 5 h,用不同乙醇浓度进行梯度洗脱,得到梓醇粗品,含量达64. 82%。     

Kinetics and Equilibrium Studies for the Removal of Cobalt,Manganese, and Silver in Ethanol using Dowex 50W-x8 Cation Exchange Resin

Organic solvents such as ethanol, find a wide range of applications in fuel, pharmaceutical industries, food industries, and paint formulations, among others. The removal of Ag(I), Co(II), and Mn(II) ions in ethanol by cation exchange resin, Dowex 50W-x8, was investigated. The adsorption characteristics of metal ions onto Dowex 50W-x8 resin were described by Langmuir isotherms. The maximum sorption exchange capacities at 298 K were obtained as 47.4 mg g^?1, 52.6 mg g^?1, and 58.5 mg g^?1 for Ag(I), Co(II), and Mn(II), respectively. The data was also fitted to Temkin and Dubinin-Radushkevich adsorption isotherm models to evaluate other adsorption properties. The ion exchange of silver, cobalt, and manganese on cation exchange resin followed pseudo-second-order kinetics, and the intraparticle diffusion was rate-determining step. The thermodynamic parameters indicated that the sorption of metal ions onto Dowex 50W-x8 resin was spontaneous (negative ΔG°) and endothermic in nature (positive ΔH°) implying that the adsorption capacity increased with increasing temperature. The resin can be regenerated by eluting metal ions with 3.0 mol L^?1 HNO₃ followed by washing it with 10 mL of Millipore water and 10 mL of 2.0 M NaOH, respectively. The proposed method was applied for metal ion removal in real ethanol samples.     

Preconcentration and Determination of Metal Ions in Commercial Ethanol Used as Fuel for Automotive Engines

Abstract

The present investigation reports the synthesis, characterization, and adsorption properties of a new nanomaterial based on organomodified silsesquioxane nanocages. The adsorption isotherms for CuCl₂, CoCl₂, ZnCl₂, NiCl₂, and FeCl₃ from ethanol solutions were performed by using the batchwise method. The equilibrium condition is reached very quickly (3 min), indicating that the adsorption sites are well exposed. The results obtained in the flow experiments, showed a recovery of ca. 100% of the metal ions adsorbed in a column packed with 2 g of the nanomaterial, using 5 mL of 1.0 mol L^?1 HCl solution as eluent. The sorption‐desorption of the metal ions made possible the development of a method for preconcentration and determination of metal ions at trace level in commercial ethanol, used as fuel for car engines. The values determined by recommended method for plants 1, 2, and 3 indicated an amount of copper of 51, 60, and 78 µg L^?1, and of iron of 2, 15, and 13 µg L^?1, respectively. These values are very close to those determined by conventional analytical methods. Thus, these similar values demonstrated the accuracy of the determination by recommended method.     

Adsorption Profile and Complexing Behavior of Hg(II) Ions onto Polyurethane Foam from Acidic Mixed Solvent System (H2O + Ethanol) Containing Dithizone

A new method has been developed to remove Hg(II) metal ion by preconcentrating onto polyurethane foam (PUF) from acidic mixed solvent system (0.5 N HNO₃ + 25% ethanol) containing dithizone. Batch experiments were carried out to assess adsorption equilibrium and kinetic behavior by varying parameters such as acid concentration, agitation time, aqueous- ethanol ratio, and metal ion concentration. These facilitated the computation of kinetic parameters and adsorption behavior. The optimum conditions of sorption of mixed solvent system are 0.5 mol L^?1 HNO₃ + 25% ethanol containing 1.95 × 10^?4 mol L^?1 of dithizone with 40 minutes of equilibrium time. The kinetic parameters indicate that sorption follows the first-order reaction and intraparticle diffusion process. The obtained data followed the adsorption models. i.e., Freundlich, Langmuir, and Dubinin–Radushkevich (D-R) isotherms successfully. The thermodynamics studies indicate that sorption increases with rise in temperature, entropy driven, and endothermic chemisorption. The nature of the sorption mechanism of Hg(II) ions with dithizone and PUF has been discussed and the composition of the adsorbed complex has been predicted. The effect of different foreign cations and anions has been investigated. The data indicates that only EDTA, thiosulphate, and cyanide are interfering. The method was applied on different synthetic mixtures and saline solution to test the selectivity of the new method for the abatement of Hg(II) ions from mixed solvent system.     

Heterogeneous synthesis of chelating resin organophosphonic acid‐functionalized silica gel and its adsorption property of heavy metal ions from fuel ethanol solutions

In this study, chelating resin silica gel chemically modified by poly(triethylenetetramine bis(methylenephosphonic acid)) (denoted as SG‐Cl‐T‐P) was successfully developed by heterogeneous synthesis method and used for adsorptive removal of heavy metal ions from fuel ethanol solutions, and the relevant modified organic group was calculated by DFT method at the B3LYP/6‐31 + G(d) level. SG‐Cl‐T‐P was characterized by Fourier transform infrared spectrometer, scanning electron microscope, energy dispersive X‐ray analysis system, porous analysis, etc. SG‐Cl‐T‐P has been used to investigate the adsorption of Hg(II),Cu(II), Mn(II), Co(II), Zn(II), Ni(II), Fe(III), and Cd(II) metal ions from ethanol solutions. The research results revealed that it has the better adsorption capacity for Hg(II) and Cd(II). © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Metal ion removal by dyed cellulosic materials

Further studies on adsorption of different metal ions by the four dyed and undyed cellulosic substrates namely cotton fibers, bleached bamboo pulp, jute fibers, and sawdust were carried out. Different metal ions adsorbed were Fe²⁺, Fe³⁺, Pb²⁺, and Hg²⁺. The equilibrium metal adsorption was studied by EDTA method. The control and dyed substrates adsorbed these metal ions to a significant extent, thus providing an effective and cheap method for adsorption of costly but polluting and toxic metals like Pb²⁺ and Hg²⁺. The adsorption levels varied up to 95% for various substrate–dye–metal ion combinations.     

磺化煤对重金属离子的吸附效果研究

磺化煤是一种价格低廉、原料广泛的具有较强吸附性能的新型吸附剂。介绍了磺化煤的制备方法采用静态法测定了磺化煤对几种重金属离子的吸附量,结果显示吸附量的顺序为Pb^2 ＞Cu^2 ＞Ni^2 ＞Zn^2 。研究了吸附时间、pH值对吸附量的影响及磺化煤在电镀废水处理中的实际应用效果,探讨了磺化煤吸附重金属离子的机理。结果表明,pH值是影响磺化煤吸附作用的主要因素,且其对实际电镀废水的吸附净化效果较好,对重金属的去除率高达99％、     

马尾松松针儿茶素提取工艺研究

采用乙醇回流法提取马尾松松针儿茶素,考察了乙醇浓度、提取温度、液料比对儿茶素得率的影响。结果显示,最优工艺条件为:乙醇浓度为60%,提取温度为60℃,料液比为1∶10(g∶mL),儿茶素得率为0.038%。     

羧甲基壳聚糖对金属离子吸附的研究进展

羧甲基壳聚糖及其改性产品的吸附性能主要体现在对各种金属离子的的吸附上.为了有选择性地吸附某些金属离子,人们通过修饰、交联、接技等方法对羧甲基壳聚糖进行了各种改性研究.文章综述了1992年以来羧甲基壳聚糖及其衍生物在金属离子吸附方面的研究进展.展望了吸附剂存重金属离子废水处理过程中的巨大优势和良好的发展前景.     

微波法合成硫脲树脂及其吸附性能研究

研究了硫脲、甲醛、对苯二酚的聚合,比较了微波辐射和常规加热对树脂产率的影响,考察了不同条件下树脂对金属离子的吸附情况。用核磁共振和红外光谱对树脂可能含有的官能团进行表征。结果表明:微波辐射与常规加热相比具有反应时间短、产率高的优点。酸性条件下树脂对Ag 的最高吸附量可达2.2mmolg-1,而相同条件下对Ni2 、Cd2 、Co2 等过渡金属离子基本不吸附,体现了该树脂在对金属离子的选择分离方面有较高的应用价值。利用含8%硫脲的1molL-1HNO3溶液洗脱经吸附过的树脂,洗脱率可达95%以上,再生的树脂吸附量仍可达到前一次的98%。     

Adsorption of Cd(II), Pb(II), and Ag(I) in aqueous solution on hollow chitosan microspheres

Cross‐linked chitosans synthesized by the inverse emulsion cross‐link method were used to investigate adsorption of three metal ions [Cd(II), Pb(II), and Ag(I)] in an aqueous solution. The chitosan microsphere, was characterized by FTIR and SEM, and adsorption of Cd(II), Pb(II), and Ag(I) ions onto a cross‐linked chitosan was examined through analysis of pH, agitation time, temperature, and initial concentration of the metal. The order of adsorption capacity for the three metal ions was Cd²⁺ > Pb²⁺ > Ag⁺. This method showed that adsorption of the three metal ions in an aqueous solution followed the monolayer coverage of the adsorbents through physical adsorption phenomena and coordination because the amino (? NH₂) and/or hydroxy (? OH) groups on chitosan chains serve as coordination sites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010