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51.
52.
用国产非离子型大孔网状树脂CAD—45吸附提取麦迪霉素,取代了传统的溶媒萃取法.试验确定了提取工艺条件:吸附最佳pH为8.3~8.5,流速为1/6ml/min;解吸前先用1%氨水1:1(V/V)洗柱;最佳解吸剂为醋酸丁酯,流速为1/12ml/min。收率可达84.8%。 相似文献
53.
A new chelating polymeric sorbent was developed by functionalizing Amberlite XAD-16 with 1,3-dimethyl-3-aminopropan-1-ol via a simple condensation mechanism. The newly developed chelating matrix offered a high resin capacity and faster sorption kinetics for the metal ions such as Mn(II), Pb(II), Ni(II), Co(II), Cu(II), Cd(II) and Zn(II). Various physio-chemical parameters like pH-effect, kinetics, eluant volume and flow rate, sample breakthrough volume, matrix interference effect on the metal ion sorption have been studied. The optimum pH range for the sorption of the above mentioned metal ions were 6.0–7.5, 6.0–7.0, 8.0–8.5, 7.0–7.5, 6.5–7.5, 7.5–8.5 and 6.5–7.0, respectively. The resin capacities for Mn(II), Pb(II), Ni(II), Co(II), Cu(II), Cd(II) and Zn(II) were found to be 0.62, 0.23, 0.55, 0.27, 0.46, 0.21 and 0.25 mmol g−1 of the resin, respectively. The lower limit of detection was 10 ng ml−1 for Cd(II), 40 ng ml−1 for Mn(II) and Zn(II), 32 ng ml−1 for Ni(II), 25 ng ml−1 for Cu(II) and Co(II) and 20 ng ml−1 for Pb(II). A high preconcentration value of 300 in the case of Mn(II), Co(II), Ni(II), Cu(II),Cd(II) and a value of 500 and 250 for Pb(II) and Zn(II), respectively, were achieved. A recovery of >98% was obtained for all the metal ions with 4 M HCl as eluting agent except in the case of Cu(II) where in 6 M HCl was necessary. The chelating polymer showed low sorption behavior to alkali and alkaline earth metals and also to various inorganic anionic species present in saline matrix. The method was applied for metal ion determination from water samples like seawater, well water and tap water and also from green leafy vegetable, from certified multivitamin tablets and steel samples. 相似文献
54.
Steam distillation is combined with solid-phase resin extraction using a simple apparatus and interface. A concentration factor of at least 100 is obtained. The method is effective for the isolation and concentration of organic compounds from complex aqueous samples ar μg l?1 levels. Factors affecting the recovery of model compounds are studied; it is shown that the recovery of many compounds is improved markedly by disconnecting the condenser. Under proper conditions, compounds with boiling points in excess of 400°C are recovered quantitatively in only 24 mill. 相似文献
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The treatment and resource reuse of 1,2,4-acid producing wastewater by self-mademacroporous adsorption resin ND,A-107 was studied in this paper. Optimum adsorption anddesorption process parameters were acquired by systematically study. The polymeric resin NDA-10 7indicated good adsorption & desorption of 1,2, 4-acid in the wastewater. The removal efficiency of1,2,4-acid, CODer is about 78%, 72% respectively. It is evident that this adsorption process is anefficient treatment method for 1,2,4-acid producing wastewater. At the same time, the accumulationand resource reuse of l,2, 4-acid can be realized in this process. 相似文献
57.
体系以聚合氯化铝溶液为原料,以硫酸型强碱性阴离子交换树脂为载体,进行离子交换反应。结果表明,在保持氧化铝含量基本不变的情况下,能有效地提高聚合铝的碱化度。同时生成含SO4^2-的聚合氯化铝,实验证明它的絮凝效果优于了聚合氯化铝。 相似文献
58.
Nathan S. Lawrence Markus Pagels Simon F. J. Hackett Sean McCormack Andrew Meredith Timothy G. J. Jones Gregory G. Wildgoose Richard G. Compton Li Jiang 《Electroanalysis》2007,19(4):424-428
A pH probe based on a carbon‐epoxy electrode design is discussed. The electrode consists of three redox active components within a carbon epoxy matrix. These are the pH sensitive species anthraquinone and phenanthrenequinone, along with the pH insensitive ferrocene reference compound. The values of the peak potentials when combined are shown to shift by 120 mV/pH unit at 25 °C with respect to the ferrocene reference potential. 相似文献
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60.
2-噻吩乙酸在3种树脂上的吸附行为研究 总被引:15,自引:0,他引:15
通过静态吸附实验 ,研究了XAD 4、NDA 10 0和ND 90吸附树脂对水溶液中 2 噻吩乙酸的吸附热力学及动力学特性 ,结果表明 ,2 噻吩乙酸在XAD 4树脂上是单层吸附 ,符合Langmuir等温吸附方程 ,吸附过程符合准一级动力学吸附方程 .2 噻吩乙酸在NDA 10 0和ND 90树脂上的吸附也能用Langmuir等温吸附方程表示 ,但并不只是单层吸附而主要是由毛细管凝聚和微孔填充作用造成的 ,吸附过程可分为大孔和中孔区的吸附以及微孔区的吸附两个阶段 ,两个阶段都符合准一级动力学吸附方程 相似文献