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The industrial application of emerging water‐lean solvents to CO2 capture from flue gas is challenged by their high viscosity. In this work, we report a novel water‐lean CO2 solvent which possesses lower viscosity and higher CO2 cyclic capacity than other water‐lean solvents reported in the literature. The new solvent consists of N, N‐dimethyl‐1, 2‐ethanediamine (DMEDA), physical cosolvent N‐methyl‐2‐pyrrolidone (NMP) and up to 15% water (named ENH). We evaluated the effect of the solvent composition on the viscosity, CO2 cyclic capacity and regeneration energy of ENH and compared it with the reference monoethanolamine (MEA) based solvents. It was found that ENH containing 5% H2O (ENH‐5%H2O) with a CO2 loading of 0.767 mol CO2·mol amine–1 had a viscosity of 7.603 mPa·S at 40 ˚C, which was comparable with that of traditional blended amines. Excellent cyclic capacity performance was also observed, with ENH‐5% H2O showing a 140% improvement compared to aqueous MEA. Regeneration energy of ENH‐5% H2O was estimated to be 2.418 GJ·tCO2–1 which is 36% lower than the 30 wt. % aqueous MEA solvent. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Aiming to solve the problem of high ammonia loss during ammonia-based CO2 chemical absorption process, an ammonia wash system was recommended to be added after the absorber column. Hence, we need to deal with a lot of wash water. Recently, we proposed a vacuum membrane distillation (VMD) system to regenerate ammonia from ammonia wash water. The stripping gaseous ammonia can be used for producing a high-concentration ammonia solution for solvent make-up in the CO2 capture system, and the wash water after distillation can be reused. In this work, we investigated 0.3 M ammonia solutions on different operation factors such as feed flow rate, feed temperature, pressure in the permeate side, and CO2 loading. The experimental results show that both temperature and pressure in the permeate side have significant influences on the ammonia stripping process. Increasing feed temperature and reducing pressure in the permeate side will not only improve ammonia removal efficiency, but also enhance total transmembrane flux and overall mass transfer coefficient. The increase of feed flow rate can improve the total transmembrane flux, but will lower the ammonia removal efficiency. The increase of CO2 loading in the feed ammonia solution will decrease the ammonia removal rate. Furthermore, we investigated a continuous circulation experiment and found that the ammonia removal efficiency largely depended on the removal time. The removal efficiency can be up to 95.6% with a 120 min continuous circulation time. We think this VMD system has the potential to recover ammonia and solve the solvent loss problem. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

The low CO2 absorption rate and high ammonia volatile loss rate are two major issues for the ammonia-based CO2 capture technology. In this work, we investigated the effect of total pressure on CO2 absorption and ammonia vaporization in ammonia solutions on a wetted-wall column. We found that the elevated pressure absorption process was an effective way to increase CO2 absorption rate and suppress ammonia vaporization at the same time. We also studied the mass transfer mechanism at elevated pressure and found the overall mass transfer coefficients of CO2 absorption in both ammonia and MEA solutions at elevated pressures were lower than that under atmospheric pressure. The overall mass transfer coefficients of CO2 absorption in 3 M NH3 (298 K) at 1, 1.5, 2, 2.5 bar were 0.723 × 10−6, 0.652 × 10−6, 0.591 × 10−6, 0.555 × 10−6 mol/(s m2 Pa) and the corresponding gas side mass transfer coefficients were 13.8 × 10−6, 4.52 × 10−6, 2.61 × 10−6, 2.03 × 10−6 mol/(s m2 Pa), respectively. We also found the gas side mass transfer coefficient in the wetted-wall column was not only dependent on the hydrodynamic conditions of the column but also influenced by the total pressure. © 2014 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

A well-defined amphiphilic block copolymer was synthesized by the coupling of carboxyl-terminated methoxy poly(ethylene glycol) (MPEG) with a hydroxyl-terminated octamer of glycolic acid, which was obtained by a stepwise synthetic procedure with the end-group protection and deprotection. The block copolymer had a polydispersity index (PDI) of 1.01, as determined by gel permeation chromatography. It was further coupled to paclitaxel to form a prodrug of paclitaxel. The paclitaxel content in the prodrug was about 10%, and its PDI was 1.02. The antitumor activity of the conjugate against human lung carcinoma A549 cells was evaluated by mitochondrial dehydrogenase (MTT) assay. The results show that paclitaxel could be released from the conjugate without losing cytotoxicity. Therefore, the well-defined amphiphilic block copolymer from MPEG and oligomer of glycolic acid could potentially provide novel opportunities to obtain reproducible pharmacokinetic behavior in the design of a drug-delivery system. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

An efficient technique for the SI-ATRP of PS at the HAP surfaces was achieved through immobilization of the macroinitiator (BIBB). FTIR, TGA, NMR, and TEM studies confirmed that the modified individual nanoparticles composed of a HAP core and well-defined, densely grafted outer PS, which demonstrated that the surface of HAP was grafted with polymer chains successfully. Then, HAP/HIPS nanocomposites with different loadings of pristine HAP and modified HAP were prepared by solution mixing. The mechanical properties of the nanocomposites increased remarkably by introducing surface-coated nanoparticles due to the strong interfacial interaction and good compatibility between the two components, which was further confirmed by the SEM images of the brittle fracture face of the nanocomposites. Compared with the corresponding HIPS samples, DSC results demonstrated that the HAP/HIPS nanocomposites exhibited higher glass transition temperature (Tg). [ABSTRACT FROM PUBLISHER]