Abstract:

To evaluate the performance of forward osmosis (FO) membrane, water permeability coefficient, solute permeability coefficient, and membrane structure parameter are three valuable independent parameters. These parameters were always evaluated by theoretical models based experimental methods. The evaluation on the FO membrane performance and the establishment of the relationship between the membrane structure and performance would be influenced by the difference between the parameters measured by different methods. Thus, on the basis of the relevant researches recently, the operating conditions, theoretical models, advantages, drawbacks and limitations of two testing methods, which were in term of reverse osmosis-forward osmosis (RO-FO) method and forward osmosis (FO) method, were compared in detail. Based on the solution diffusion model and concentration polarization theory, these two methods could be carried out simply with limited application range and slightly reduced testing accuracy, due to their assumptions. The parameters testing accuracy could be improved by optimizing the theoretical model, whose applicability still remains to be verified.

Key words: forward osmosis, membrane characterization, water permeability coefficient, solute permeability coefficient, structural parameter

摘要：

纯水渗透系数、溶质渗透系数和结构参数是评价正渗透膜性能的三个关键特征参数，其通常采用实验测试和理论模型相结合的方法测得，但不同方法测得特征参数间的差异会影响其对正渗透膜性能的准确评价和膜结构与性能间关系的建立。针对上述问题，本文在归纳和总结近年来国内外相关研究的基础上，详细分析了正渗透膜特征参数测试方法和理论模型的特点及发展现状，比较了反渗透-正渗透法和正渗透法的优缺点和局限性。基于溶解扩散模型和浓差极化理论所建立的反渗透-正渗透法和正渗透法，其模型简单、便于计算，但其假设具有局限性，影响了方法的实施和结果的准确性。优化理论模型可提高正渗透膜特征参数测定的准确性，但新模型的稳定性和适用范围仍需验证。

关键词: 正渗透, 膜表征, 纯水渗透系数, 溶质渗透系数, 膜结构参数