The development of membranes and membrane-based separation processes should be accompanied by a standardization of the protocols applied for membrane characterization and for data analysis. Here, streamlined equations for the estimation of the water flux and of the observed salt permeability coefficient in pressure-driven processes deploying dense membranes are presented. Also, a protocol for the experimental characterization of the transport properties of dense membranes is presented and the results are validated against the proposed equations. The proposed water flux equation is algebraic, whereas the ordinary equation needs to be solved iteratively. Moreover, in contrast to the traditional expression for the solute transport coefficient, which requires estimation of the concentration polarization, the respective equation proposed in this study only requires bulk parameters. Dimensionless variables for water flux, driving pressure, and mass transfer are introduced, and a filtration efficiency is defined, a useful parameter in terms of process design.

膜和基于膜的分离工艺的发展应伴随着用于膜表征和数据分析的协议的标准化。这里提出了用于估计部署致密膜的压力驱动过程中的水通量和观察到的盐渗透系数的简化方程。此外，还提出了致密膜传输特性的实验表征协议，并根据所提出的方程验证了结果。所提出的水通量方程是代数方程，而普通方程需要迭代求解。此外，与需要估计浓差极化的溶质输运系数的传统表达式相反，本研究中提出的相应方程仅需要大量参数。引入了水通量、驱动压力和传质的无量纲变量，并定义了过滤效率，这是工艺设计方面的一个有用参数。