The concept of phase change absorbents has been widely studied as a novel and low-energy consumption option for CO 2 capture. This work screened diethylene glycol dimethyl ether (DGM) from 17 physical solvent species as a better phase change accelerator for absorbents of 2-(methylamino)ethanol (MAE)-physical solvent-H 2 O. Then, the optimized mass ratio of 30:49:21 for MAE-DGM-H 2 O solution was investigated with phase change behaviors, CO 2 absorption–desorption performance, cyclic capacity, and energy consumption. The experimental results showed that the cyclic CO 2 capacity reached 1.32 mol/L and the CO 2 -rich phase made up only 50.4 % of the total volume for the 30 wt%MAE-49 wt%DGM-21 wt%H 2 O, as well as its regenerative energy consumption was 40 % lower than that of 30 wt% monoethanolamine (MEA) solution. Also, the viscosity and surface tension gap of the CO 2 -rich phase and CO 2 -lean phase for the optimized absorbent were studied. It was observed that those gaps increase with the increasing mass ratio of DGM. In addition, the possible phase change mechanism was proposed by using the dipole moment values of components calculated by Gaussian (B3LYP/6-31G) coupled with 13 C NMR spectra.
Water-lean liquid–liquid biphasic absorbents have recently received increasing attention due to the potential advantages for capturing low CO 2 concentration flue gas with high efficiency in capture rate and energetic aspects. However, performance assessment has rarely been performed in a lab-scale continuous and integrated capture plant. In this work, a water-lean biphasic system containing 2-(methylamino) ethanol (M), diglyme (D) and water (H) was proposed for about 5 vol% CO 2 exhaust gas treatment based on the batch absorption–desorption capture tests. Integrated phase changing capture process using the developed absorbent formulation 40 M−50D−10H (WLS-10C) was demonstrated in a lab-scale CO 2 capture plant over 200 hrs testing. Energetic and capture performance as well as operational stability were evaluated and compared with aqueous 30 mass % MEA under the same targeted capture rate (about 90 %). The stable phase change behavior after CO 2 absorption was observed in the phase separator, and the CO 2 rich phase can be effectively regenerated at 393 K, forming a monophasic solution in the feed tank with the CO 2 lean phase from the separator for solvent reuse. This biphasic WLS-10C can reduce the energy consumption by about 45–55 % compared with aqueous MEA at about 90 % capture rate, demonstrating a pronounced energy-saving effect. Moreover, volumetric mass transfer coefficient and viscosity were also discussed. These findings provide valuable insights into the further pilot demonstration of the proposed biphasic absorbent.
Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease characterized by lung inflammation and excessive deposition of extracellular matrix components. Transforming growth factor-β1 (TGF-β1) induced epithelial–mesenchymal transformation of type 2 lung epithelial cells leads to excessive extracellular matrix deposition, which plays an important role in fibrosis. Our objective was to evaluate the effects of 3-cyclopropylmethoxy-4-(difluoromethoxy) benzoic acid (DGM) on pulmonary fibrosis and aimed to determine whether EMT plays a key role in the pathogenesis of pulmonary fibrosis and whether EMT can be used as a therapeutic target for DGM therapy to reduce IPF. Firstly, stimulation of in vitro cultured A549 cells to construct EMTs with TGF-β1. DGM treatment inhibited the expression of proteins such as α-SMA, vimentin, and collagen Ⅰ and increased the expression of E-cadherin. Accordingly, Smad2/3 phosphorylation levels were significantly reduced by DGM treatment. Secondly, models of tracheal instillation of bleomycin and DGM were used to treat rats to demonstrate their therapeutic effects, such as improving lung function, reducing lung inflammation and fibrosis, reducing collagen deposition, and reducing the expression of E-cadherin. In conclusion, DGM attenuates TGF-β1-induced EMT in A549 cells and bleomycin-induced pulmonary fibrosis in rats.Keywords:IPF;A549;EMT;TGF-β1/Smad;ECM