The objective of this study was to investigate the pore size distribution (PSD) of nanofiltration (NF) membranes using gas
adsorption and Atomic Force Microscopy (AFM) methods and to elucidate the mechanisms responsible for the
passage of different solutes (Rhodamine-WT, arsenious acid and sodium chloride)
through nanofiltration (NF) membranes. Rhodamine-WT (R-WT), a fluorescent chemical with
molecular weight of 480 Daltons and approved for use as a tracer chemical in drinking
water, was used as a surrogate for organic solutes. R-WT concentrations were measured
using a Bowman Series 2 Luminescence Spectrometer.
An excitation wavelength of 550 nm and emission wavelength of 570-700 nm were used.
The minimum quantification level was 50 ng/L. Two inorganic solutes were also studied,
sodium chloride and sodium arsenite. Chloride ion was analyzed by ion chromatography
Standard Method 4110B using a Dionex Ion Chromatograph Model DX-300, and the concentration of arsenious acid was determined by a Thermo
Elemental ExCell Inductively Coupled Plasma/Mass Spectrometry (ICP-MS) using Yttrium as an internal standard.
Lab-scale experiments were performed with a closed-loop system consisting of two flat-leaf cells connected in series. Each flat-leaf cell consisted of two stainless steel
316 plates, separated by a membrane coupon sealed by two o-rings placed in the bottom
plate. Feed water went into each cell and circulated through a feed channel in the bottom
plate parallel to the membrane surface. Experiments were performed with small coupons cut from a sheet of
ESNA or TFCS NF membranes. Includes 2 references, table, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 430 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 8 |
| Published : | 06/15/2003 |
