英语翻译Although CS flat-sheet membranes or CS composite membran

英语翻译
Although CS flat-sheet membranes or CS composite membranes (supported on other flat sheets or hollow fibers) have been prepared,[8][19-21] these membranes have appeared to be relatively less attractive because of their small specific surface areas or the small amount of CS contained and,hence,low adsorption capacity for adsorptive separation.[8] To increase the specific surface area,hollow-fiber membranes are usually the preferred membrane configuration (because of the high packing density).[21] Unfortunately,CS has encountered significant difficulty in the preparation of hollow-fiber membranes with adequate mechanical strength so far.CS solutions have very high viscosities,and the polymer dope solutions used to spin the hollow-fiber membranes usually unavoidably have a low CS concentration (often 5 wt %).There have been three representative reports in the literature about the preparation of CS hollow-fiber membranes.[22-24] The authors of the first two studies[22][23] prepared CS dope solutions with about 3-5 wt % concentrations,and the spun hollow-fiber membranes did not seem to have good self-supporting capability in wet state.The third study reported[24] CS dope solutions with concentrations up to 7 wt % by using Low-viscosity CS,and the strength of the spun hollow-fiber membranes was increased by increasing the crystallinity of CS in the spinning process.Not only does the requirement for low-viscous CS limit the choice of CS products in the market,a higher crystallinity also reduces the adsorption capacity of CS and is,therefore,not desirable for adsorptive CS membranes.
The major obstacle in preparing CS hollow-fiber membranes with a high mechanical strength arises,to a large extent,from the practical difficulty of obtaining highly concentrated homogeneous CS dope solutions to spin the hollow-fiber membranes.In this study,a novel method was developed to prepare homogeneous and high-concentration CS dope solutions (up to 18 wt %).CS hollow-fiber membranes fabricated from these high concentration CS solutions showed good mechanical strengths.Adsorption studies for copper-ion removal with the prepared CS fibers showed very high adsorption capacities (copper ions were used in this study as a model heavy metal for easy comparison with some early results reported in the literature).

尽管c flat-sheet膜或CS复合膜(支持其他平片或中空纤维膜)已经准备好了,[8][19-21]这些膜相对较少出现了具有吸引力,因为他们的小特殊表面区域或少量的密室中较低,因此,吸附容量为吸附分离.[8]增加了中空纤维超滤膜的比表面积,通常是首选的膜结构(因为封装密度高.)[m].北京:21]不幸遇到很大的难度,c在准备中空纤维超滤膜的机械强度和适当为止.CS方案有很高的粘度、聚合物涂料方案用于旋转中空纤维超滤膜通常都很低浓度难免CS(通常5股份).有三种代表性的文献报道关于制备的中空纤维超滤膜22-24.[c],作者在前两项研究(22)[m].北京:23]预备方案与有关3-5 CS涂料股份的浓度,与纺中空纤维超滤膜似乎没有好的自立能力在湿的状态.第三项研究报告(24)CS涂料方案与浓度达到7股份利用低粘度、和强度中空纤维超滤膜纺提高结晶度的密室中增加了纺纱工艺流程.它不仅要求的选择low-viscous CS限制CS产品在市场、更高的结晶度也降低了吸附容量大,因此,c、不合宜的吸附CS膜.
主要的障碍和中空纤维超滤膜的制备CS机械强度高,在很大程度上,从实际困难,均取得高度集中的解决方案来旋转CS涂料中空纤维超滤膜.在这项研究中,提出了一种新颖的方法来准备均匀、高浓度溶液(CS涂料股份).中空纤维超滤膜从CS CS解决这些高浓度显示出良好的机械力量.为copper-ion吸附研究,准备CS纤维显得非常高的吸附能力(铜离子被应用于该研究作为模型比较容易重金属的一些早期的文献报告).