Membranes Naphthalene data

SAFETY PROFILE Confirmed carcinogen with experimental tumorigenic data by skin contact. Human systemic effects by inhalation unspecified effects on olfaction and respiratory systems. Corrosive effects on the skin, eyes, and mucous membranes by inhalation. Flammable when exposed to heat or flame. Will react with water or steam to produce heat and toxic and corrosive fumes. Violent or explosive reaction with dimethyl sulfoxide, and aluminum chloride + naphthalene. To fight fire, use alcohol foam, CO2, dry chemical. Incompatible with dimethyl sulfoxide, (NaNs + KOH), water, steam, and oxidizers. When heated to decomposition it emits toxic fumes of CT, See also CHLORIDES and ALDEHYDES. 

Extensive data were collected on primary pollutants (phenols, and PAHs) and on secondary pollutants (oil, suspended and dissolved solids, COD, dioxins, and VOC s). The results of this project demonstrated the ability of the formed-in-place membrane, operating in a cross-flow mode, to minimize fouling, and to remove polynuclear aromatic hydrocarbons from the contaminated feed water. As operated, rejection of the PAHs appears to increase with the number of aromatic rings. However, similar correlations appear to exist with molecular weight as well as with the partition coefficient reflecting hydrophobicity. The permeate, accounting for approximately 80% of the feedwater, contained only about 12% of the predominant PAHs, naphthalene and phenanthrene. 

Fig. 33 Swelling data for different 1.3 meq/g BDSA-based SPl membranes phthalic ODA (A) and naphthalenic ODA/fluorenyl 1 1 ( ) ODA ( ) diaminooctane (DAO) with five sulfonated monomers in the ionic sequence ( and DAO with nine sulfonated monomers (x). Swelling data are expressed as water uptake in w/w% (up) and as the number of water molecules per sulfonate group, 2.

Nowadays, PEMFCs operate at 80 °C and one of the main objectives is to increase this temperature as much as possible. Thus, the water uptake has to be measured as a function of temperature or at least at elevated temperature. For most of the ionomer membranes, the water uptake increases almost exponentially with temperature up to partial or total dissolution [135,142]. In the early work of Faure et al. [29], the SPI water uptake was shown to be independent of the temperature in the range of room temperature to 80 °C for naphthalenic SPIs, while a slight increase was observed for phthalic SPIs as confirmed recently [50]. However, phthalic SPIs are very sensitive to hydrolysis, which induces a fast polymer degradation [29,50]. This sensitivity increases with temperature and the swelling data recorded at elevated temperature should be considered with care [68]. 

Fig. 37 SANS spectra of flexible phthalic (A) and rigid naphthalenic ( ) SPI membranes soaked in deuterated water. The SANS spectrum of a water-swollen Nafion membrane is given as reference ( ). The data were normalized by the scattering invariant for comparison...

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