Fabrication of polydimethylsiloxane mixed matrix membranes for recovery of ethylene glycol butyl ether from water by pervaporation

• Published in: Journal of membrane science Vol. 665; p. 121138
• Main Authors: Wang, Ting, Huang, Xiao-xing, Huang, Lu-lu, Wu, Li-guang, Zhu, Dong-feng, Wang, Guo-qin, Jiang, Xiao-jia
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.01.2023
• Subjects: Ethylene glycol butyl ether; Mixed matrix membranes; Pervaporation; Polydimethylsiloxane; Ethylene glycol butyl ether; Polydimethylsiloxane; Pervaporation; Mixed matrix membranes
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2022.121138

Due to its wide application as a solvent or cleaning agent in automotive paints and other coatings industries, the separation and recovery of ethylene glycol butyl ether (EB) from wastewater played a key role in reducing emissions in industries such as automotive coatings. To achieve the efficient separation of EB by pervaporation process, three different types of nanomaterials were first used as additives to construct the mixed matrix membranes (MMMs) for pervaporation using polydimethylsiloxane (PDMS) as the polymer material. The addition of three nanomaterials could improve the affinity of the resulting MMMs toward EB and accelerate the diffusion process of EB in MMMs, thus eventually enhancing the separation performance of the resulting membranes. When three nanomaterials seriously agglomerated in polymeric materials, the improvement of the EB diffusion in MMMs decreased. Moreover, the diffusion of EB molecules in the MMMs containing nanomaterials was still lower than that of water molecules due to the insufficient capturing of EB, and the diffusion selectivity of the resulting MMMs for EB was less than 1. The surface modification for nanomaterials by grafting polyethylene glycol (PEG) could enhance the affinity between PEG-grafted nanomaterials and EB molecules, which simultaneously improved the swelling performance of MMMs and the diffusion process of EB in MMMs. Owing to the stronger affinity between the PEG2000-grafted nanomaterials containing more ether groups and EB molecules, PDMS incorporated with PEG2000-grafted nanomaterials exhibited the best membrane flux (730 g m−2 h−1) and selectivity (30), which was twice that of the commercial membrane. Furthermore, the PDMS incorporated with PEG2000-grafted nanomaterials maintained excellent and stable performance for separating EB during pervaporation for 20 h, while the separation performance of the commercial membrane decreased significantly after 12 h of pervaporation experiments. Therefore, the MMMs fabricated in this work are promising candidates for the separation and recovering the ether solvents through membrane technology. [Display omitted] •Three nanomaterials were used as additives to construct the PDMS MMMs.•Adding three nanomaterials could improve the affinity of the resulting MMMs with EB.•MMMs with PEG-grafted nanomaterials had the high performance for EB separation.•Incorporation of PEG-grafted nanomaterials accelerated the EB diffusion in the MMMs.