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Hydrophobic poly(ether ether ketone) (PEEK) were modified by sulfonation at different temperatures (22, 36, 45, and 55°C) and varying period of time with concentrated sulfuric acid used as solvent. A kinetic study was carried out based on the assumption that sulfonation reaction is a second-order reaction, which takes place preferentially in the aromatic ring between the two ether (OOO) links (the first type substitution), and there is only one substituent attached to each repeat unit of the PEEK before the complete substitution of this preferred aromatic ring. More than 100% substitution was observed in experiment. All the data with substitution degree less than 95% agree fairly well with the kinetic behavior of the second-order reaction. The reaction rate coefficient and activation energy for first type substitution were obtained. The sulfonated PEEK samples were characterized in terms of ion-exchange capacity (IEC), 1 H-NMR, contact angle, and solubility.

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Pervaporation separation of ethylene glycol aqueous solutions was carried out using sulfonated poly(ether ether ketone) homogeneous membranes. Membrane relaxation in separation processes was observed and alleviated by heat treatment. The heat-treated pervaporation membranes experience further relaxation in the separation process by the swelling interactions of the feed mixtures before steady-state transport is reached. Membrane performance is investigated in terms of sorption and pervaporation separation. The preferential sorption and diffusion of water in the membranes were observed. Membrane performance can be interpreted by the modified solution-diffusion model, which takes into account the plasticization interaction of the transporting species in the membrane. Some parameters in this model were estimated by fitting the related experimental data. The benefit of using pervaporation for ethylene glycol dehydration is discussed in terms of energy consumption.

/npsi/ctrl?lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?lang=fr Access and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. For the publisher's version, please access the DOI link below./ Pour consulter la version de l'éditeur, utilisez le lien DOI ci-dessous.http://dx.doi.org/10.1016/j.memsci.2012.09.044Journal of Membrane Science, 427, pp. 451-459, 2012-10-12 Simulation of membrane-based CO2 capture in a coal-fired power plant Shao, Pinghai; Dal-Cin, Mauro M.; Guiver, Michael D.; Kumar, Ashwani AbstractA two-stage membrane process is designed for CO 2 capture from coal-fired power plants.Vacuum operation on the permeate side of the membrane is the preferred option to reduce the power demand for compressing the huge feed volume. The energy recovered from the CO 2 -depleted emission stream and the energy consumed for post-capture CO 2 liquefaction are considered in this simulation study. A numerical modeling of the membrane process and a brief description on assessing both the capital and operating costs of the process are provided. It is found that the membrane area requirement is dominated by recovery of the lower concentrations of CO 2 in the tail portion of the flue gas stream. Process optimizations allowing the minimal CO 2 capture cost or minimal power demand indicate that current membrane technology is promising for flue gas CO 2 capture. The potential of membrane technology for CO 2 capture was also explored by using membranes with a CO 2 /N 2 selectivity of 50 and 200.