Size sieving and electrostatic exclusion synergetic strategy for high efficiency recovery of superbase-derived ionic liquids via nanofiltration from the spinning process
{"title":"Size sieving and electrostatic exclusion synergetic strategy for high efficiency recovery of superbase-derived ionic liquids via nanofiltration from the spinning process","authors":"","doi":"10.1016/j.seppur.2024.129851","DOIUrl":null,"url":null,"abstract":"<div><div>Superbase-derived ionic liquids (SILs) as the promising green solvents for cellulose spinning process should be urgently and deeply evaluated with respect to their recyclability. Herein, size sieving and electrostatic exclusion synergetic strategy was adopted for recycling four SILs ([DBUH][CH<sub>3</sub>CH<sub>2</sub>OCH<sub>2</sub>COO], [DBUH][CH<sub>3</sub>OCH<sub>2</sub>COO], [DBNH][CH<sub>3</sub>CH<sub>2</sub>OCH<sub>2</sub>COO], and [DBNH][CH<sub>3</sub>OCH<sub>2</sub>COO]) from aqueous solutions by the nanofiltration membranes (NF270 and NF90) at the first time. NF270 with larger pore and more negative charge was conducive to recycle SIL on account of a higher volume flux and the remarkably high IL rejection (>95 %) compared to NF90. Rising the pressure and temperature played the positive role in the permeate flux of the membranes, whereas the elevated SIL concentration markedly decreased the electrostatic exclusion, leading to a decline in the recovery efficiency. Benefiting from the size sieving effect, the [DBNH][CH<sub>3</sub>OCH<sub>2</sub>COO] with small cation and anion structure could be recovered efficiently due to the high energy gap and big IL aggregates. Conversely, the strong electrostatic attraction was appeared between [DBUH][CH<sub>3</sub>CH<sub>2</sub>OCH<sub>2</sub>COO] (low energy gap and high positive charge density) and the membranes, leading to a decline in recovery efficiency. Furthermore, the combination of nanofiltration and evaporation to recover SIL from spinning wastewater effectively reduced the total recovery cost (1.51 $/Kg) in comparison with the evaporation only. Insight gained from this work suggested a high-efficiency and economical approach could be used in the recovery of SILs with small cations and anions size via large pore nanofiltration membranes during the industrialized cellulose spinning process.</div></div>","PeriodicalId":427,"journal":{"name":"Separation and Purification Technology","volume":null,"pages":null},"PeriodicalIF":8.1000,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Separation and Purification Technology","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1383586624035901","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Superbase-derived ionic liquids (SILs) as the promising green solvents for cellulose spinning process should be urgently and deeply evaluated with respect to their recyclability. Herein, size sieving and electrostatic exclusion synergetic strategy was adopted for recycling four SILs ([DBUH][CH3CH2OCH2COO], [DBUH][CH3OCH2COO], [DBNH][CH3CH2OCH2COO], and [DBNH][CH3OCH2COO]) from aqueous solutions by the nanofiltration membranes (NF270 and NF90) at the first time. NF270 with larger pore and more negative charge was conducive to recycle SIL on account of a higher volume flux and the remarkably high IL rejection (>95 %) compared to NF90. Rising the pressure and temperature played the positive role in the permeate flux of the membranes, whereas the elevated SIL concentration markedly decreased the electrostatic exclusion, leading to a decline in the recovery efficiency. Benefiting from the size sieving effect, the [DBNH][CH3OCH2COO] with small cation and anion structure could be recovered efficiently due to the high energy gap and big IL aggregates. Conversely, the strong electrostatic attraction was appeared between [DBUH][CH3CH2OCH2COO] (low energy gap and high positive charge density) and the membranes, leading to a decline in recovery efficiency. Furthermore, the combination of nanofiltration and evaporation to recover SIL from spinning wastewater effectively reduced the total recovery cost (1.51 $/Kg) in comparison with the evaporation only. Insight gained from this work suggested a high-efficiency and economical approach could be used in the recovery of SILs with small cations and anions size via large pore nanofiltration membranes during the industrialized cellulose spinning process.
期刊介绍:
Separation and Purification Technology is a premier journal committed to sharing innovative methods for separation and purification in chemical and environmental engineering, encompassing both homogeneous solutions and heterogeneous mixtures. Our scope includes the separation and/or purification of liquids, vapors, and gases, as well as carbon capture and separation techniques. However, it's important to note that methods solely intended for analytical purposes are not within the scope of the journal. Additionally, disciplines such as soil science, polymer science, and metallurgy fall outside the purview of Separation and Purification Technology. Join us in advancing the field of separation and purification methods for sustainable solutions in chemical and environmental engineering.