反渗透复合膜(Ⅰ)结构与性能

Reverse osmosis composite membrane(Ⅰ) Chemical structure and performance

Three composite reverse osmosis membranes were prepared from m-phenylenediamine (MPD) and trimesoyl chloride (TMC), 5-chloroformate-isophthaloyl chloride (CFIC), 5-isocynate-isophthaloyl chloride (ICIC) respectively through the interfacial polymerization technique on the polysulphone supporting membrane.The membranes produced were characterized by using permeation experiments with salt water, attenuated total reflectance infrared (ATR-IR), and X-ray photoelectronic spectroscopy (XPS).This study showed that with the increase of NaCl concentration, the flux of the three membranes decreased; the rejection of TMC/MPD, ICIC/MPD composite membranes increased firstly and then decreased; but the rejection of CFIC/MPD composite membrane kept steady.According to the ATR-IR and XPS results, the active layer of three membranes was composed of crosslinked polymer and linear polymer with pendant; all three composite membranes contained amide functional group( —CONH? ゛nd carboxyl acid functional group( —COOH ); the ICIC/MPD composite membrane contained urea functional group( —NHCONH? ? the CFIC/MPD composite membrane also contains urethane functional group( —OCONH? ゛nd hydroxyl functional group( —OH ).The hydroxyl functional group could lead to high rejection and low flux.

Three composite reverse osmosis membranes were prepared from m-phenylenediamine （MPD） and trimesoyl chloride （TMC）, 5-chloroformate-isophthaloyl chloride （CFIC）, 5-isocynate-isophthaloyl chloride （ICIC） respectively through the interracial polymerization technique on the polysulphone supporting membrane. The membranes produced were characterized by using permeation experiments with salt water, attenuated total reflectance infrared （ATR-IR）, and X-ray photoelectronic spectroscopy （XPS）. This study showed that with the increase of NaC1 concentration, the flux of the three membranes decreased; the rejection of TMC/MPD, ICIC/MPD composite membranes increased firstly and then decreased ; but the rejection of CFIC/MPD composite membrane kept steady. According to the ATR-IR and XPS results, the active layer of three membranes was composed of crosslinked polymer and linear polymer with pendant; all three composite membranes contained amide functional group （-CONH-） and carboxyl acid functional group （-COOH） ; the ICIC/MPD composite membrane contained urea functional group （-NHCONH-）; the CFIC/MPD composite membrane also contains urethane functional group （-OCONH-） and hydroxyl functional group （-OH）. The hydroxyl functional group could lead to high rejection and low flux.