Many chemical species are involved in the feed solution (FS) in a forward osmosis (FO) process used for water/wastewater treatment and desalination. Chemicals and their molecular interactions in FS could have variable influences on water transfer and permeability, and consequently the overall performance of the FO process. This fundamental is important for understanding molecular transfer mechanisms in FO system, but has received a little attention. This preliminary study associated with its systematic investigations aimed to discover the impacts of physical and chemical properties (chemical composition, diffusivity, molar mass and charges) of FS on the water transfer characteristics and permeability in a FO desalination system. We evaluated the water flux in FS containing different salts in natural water and seawater. Our results revealed that water permeability can be significantly affected by the chemical constituents and molecular weights of FS. Water flux profiles follow an order of cations in FS: Na⁺ > K⁺ > Mg²⁺ > Ca²⁺, while high water flux reduction was found in K⁺ and NO₃⁻ FS. Solute diffusivity in FS was evidenced to play a crucial role in the water permeability. High water flux was determined in the FS with K⁺ and NO₃⁻ as which have the high diffusion coefficient. Experimental data showed that water flux could be affected by ionic mass and charge of solutes in FS as analysed by ratio of charge to molar mass (Z/M). Water flux reduction follows an increase of Z/M. This preliminary study raises insight to getting better understanding of molecular interactions in the chemically complex FS and their impact on the water transfer mechanisms in FO system.

在用于水/废水处理和脱盐的正向渗透 (FO) 过程中，进料溶液 (FS) 中涉及许多化学物质。FS 中的化学品及其分子相互作用可能对水的传递和渗透性产生不同的影响，从而影响 FO 过程的整体性能。这个基础对于理解 FO 系统中的分子转移机制很重要，但受到了一些关注。这项初步研究与其系统调查相关，旨在发现 FS 的物理和化学特性（化学成分、扩散率、摩尔质量和电荷）对 FO 脱盐系统中的水传输特性和渗透率的影响。我们评估了天然水和海水中含有不同盐分的 FS 中的水通量。我们的结果表明，FS 的化学成分和分子量会显着影响透水性。水通量分布遵循 FS 中的阳离子顺序：Na⁺  > K ⁺  > Mg ²⁺  > Ca ²⁺，而在 K ⁺和 NO ₃ ⁻ FS 中发现高水通量降低。FS 中的溶质扩散率被证明在水渗透率中起着至关重要的作用。在 FS 中用 K ⁺和 NO ₃ ^-测定了高水通量因为具有高扩散系数。实验数据表明，水通量可能受 FS 中溶质的离子质量和电荷的影响，如通过电荷与摩尔质量之比 (Z/M) 分析。随着 Z/M 的增加，水通量减少。这项初步研究为更好地了解化学复杂的 FS 中的分子相互作用及其对 FO 系统中水转移机制的影响提供了见解。