Decreasing waste brine volume from anion exchange with nanofiltration: implications for multiple treatment cycles

2021 ◽  
Author(s):  
Julie A. Korak ◽  
Leah C. Flint ◽  
Miguel Arias-Paić
Keyword(s):  
Ion Exchange ◽  
Anion Exchange ◽  
Hexavalent Chromium ◽  
Implementation Cost ◽  
Multiple Treatment ◽  
Brine Disposal ◽  
Brine Volume ◽  
Regeneration Cycle

Ion exchange (IX) removes hexavalent chromium from water, but waste brine disposal makes implementation cost-prohibitive in many communities. Nanofiltration treats waste brine for reuse in the next regeneration cycle.

scholarly journals Selective capture of hexavalent chromium from an anion-exchange column of metal organic resin–alginic acid composite

2016 ◽  
Vol 7 (3) ◽  
pp. 2427-2436 ◽  
Author(s):  
Sofia Rapti ◽  
Anastasia Pournara ◽  
Debajit Sarma ◽  
Ioannis T. Papadas ◽  
Gerasimos S. Armatas ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Anion Exchange ◽  
Hexavalent Chromium ◽  
Alginic Acid ◽  
Anion Exchange Column ◽  
Exchange Column ◽  
Ion Exchange Column ◽  
Metal Organic ◽  
Organic Resin

An ion-exchange column of metal organic resin (MOR-1)–alginic acid (HA) composite shows remarkable efficiency and selectivity for sorption of Cr(vi).

Removal of hexavalent chromium by anion exchange: Behavior of non-target anions and practical implications

2021 ◽  
Author(s):  
Leah C Flint ◽  
Miguel S Arias-Paic ◽  
Julie A Korak
Keyword(s):  
Drinking Water ◽  
Ion Exchange ◽  
Anion Exchange ◽  
Hexavalent Chromium ◽  
Water Sources ◽  
Chromium Removal ◽  
Drinking Water Sources ◽  
Practical Implications

Ion exchange is effective for hexavalent chromium removal from drinking water sources, but non-target anions (i.e., arsenic, vanadium, and uranium) that co-occur in water sources must be assessed to inform,...

ION Exchange Characterisation of Modified Zeolite

1992 ◽  
Vol 26 (9-11) ◽  
pp. 2269-2272 ◽  
Author(s):  
Š Cerjan-Stefanovic ◽  
M. Kaštelan-Macan ◽  
T. Filipan
Keyword(s):  
Drinking Water ◽  
Ion Exchange ◽  
Anion Exchange ◽  
Natural Zeolite ◽  
Deionized Water ◽  
Isomorphous Substitution ◽  
Waste Waters ◽  
Modified Zeolite ◽  
Water Drinking

Isomorphous substitution of phosphorus into a natural zeolite affords the possibility to change the overall framework charge from negative to positive. The substances so created should be used for purification of waste waters. The work describes the preparation of phosphated zeolite, their characterisation and examples of their anion exchange of NO3 on observed in deionized water, drinking water and in the solution containing varying amounts of nitrate.

scholarly journals Transport Characteristics of CJMAED™ Homogeneous Anion Exchange Membranes in Sodium Chloride and Sodium Sulfate Solutions

2021 ◽  
Vol 22 (3) ◽  
pp. 1415
Author(s):  
Veronika Sarapulova ◽  
Natalia Pismenskaya ◽  
Valentina Titorova ◽  
Mikhail Sharafan ◽  
Yaoming Wang ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Anion Exchange ◽  
Volume Fraction ◽  
Exchange Capacity ◽  
Polymer Materials ◽  
Transport Numbers ◽  
Anion Exchange Membranes ◽  
Microheterogeneous Model ◽  
Pass Through ◽  
Pes Membrane

The interplay between the ion exchange capacity, water content and concentration dependences of conductivity, diffusion permeability, and counterion transport numbers (counterion permselectivity) of CJMA-3, CJMA-6 and CJMA-7 (Hefei Chemjoy Polymer Materials Co. Ltd., China) anion-exchange membranes (AEMs) is analyzed using the application of the microheterogeneous model to experimental data. The structure–properties relationship for these membranes is examined when they are bathed by NaCl and Na2SO4 solutions. These results are compared with the characteristics of the well-studied homogenous Neosepta AMX (ASTOM Corporation, Japan) and heterogeneous AMH-PES (Mega a.s., Czech Republic) anion-exchange membranes. It is found that the CJMA-6 membrane has the highest counterion permselectivity (chlorides, sulfates) among the CJMAED series membranes, very close to that of the AMX membrane. The CJMA-3 membrane has the transport characteristics close to the AMH-PES membrane. The CJMA-7 membrane has the lowest exchange capacity and the highest volume fraction of the intergel spaces filled with an equilibrium electroneutral solution. These properties predetermine the lowest counterion transport number in CJMA-7 among other investigated AEMs, which nevertheless does not fall below 0.87 even in 1.0 eq L−1 solutions of NaCl or Na2SO4. One of the reasons for the decrease in the permselectivity of CJMAED membranes is the extended macropores, which are localized at the ion-exchange material/reinforcing cloth boundaries. In relatively concentrated solutions, the electric current prefers to pass through these well-conductive but nonselective macropores rather than the highly selective but low-conductive elements of the gel phase. It is shown that the counterion permselectivity of the CJMA-7 membrane can be significantly improved by coating its surface with a dense homogeneous ion-exchange film.

Recovery of Hexavalent Chromium Ion from Methanol with Ion Exchange Resin

2007 ◽  
Vol 40 (5) ◽  
pp. 447-453 ◽  
Author(s):  
Kazuaki Yamagiwa ◽  
Tetsunori Yamashita ◽  
Toshiaki Kamimura ◽  
Tadaaki Shimizu ◽  
Akira Ohkawa
Keyword(s):  
Ion Exchange ◽  
Hexavalent Chromium ◽  
Exchange Resin ◽  
Ion Exchange Resin ◽  
Chromium Ion

scholarly journals Boron Removal from Aqueous Solutions by Strong Base Anion-exchange Resin Batch and Column Experiments

2021 ◽  
Author(s):  
György Pátzay ◽  
József Dobor ◽  
Emil Csonka ◽  
Gábor Lozsi ◽  
Ferenc Feil
Keyword(s):  
Ion Exchange ◽  
Acid Solution ◽  
Boric Acid ◽  
Anion Exchange ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Free Water ◽  
Sulfate Solution ◽  
Boric Acid Solution ◽  
Strong Base

Borate ion exchange capacity of Purolite NRW600 strong base anion resin in hydroxide form and mixed bed NRW600+NRW100 ion exchange was investigated with static experiments. Anion exchange resin was saturated with 0.1–45 g/dm3 concentration boric acid solution in a static mixer at 20, 30, 40 and 50 °C at 150 rpm for 24 hours. Remaining borate content of saturation solutions was deter-mined with ion chromatography and ICP-OES. The amount of fixed borate as borate anions increased with the saturation borate concentration as well as in case of simple anion exchange as in case of mixed bed.Column sorption-elution study was carried out by using strong base anion exchange resins (Purolite NRW600 and Amberlite IRN78). Resins in hydroxide and in chloride forms were saturated in column with 5–40 g/dm3 boric acid solution in excess. The resin was then eluted with 200 cm3 salt free water with 5 cm3/min at 25 °C and then eluted by 1 mol/dm3 sodium-sulfate solution with 5 cm3/min. The effluent was collected and analyzed for borate content by titrimetric method. In chloride form the resin adsorbed and released much less borate. Effective borate and polyborate sorption needs hydroxide ions in resin phase.

scholarly journals Removal of Hexavalent Chromium Ions from Aqueous Solutions by an Anion-Exchange Resin

2008 ◽  
Vol 26 (9) ◽  
pp. 693-703 ◽  
Author(s):  
P. Senthil Kumar ◽  
K. Kirthika ◽  
K. Sathish Kumar
Keyword(s):  
Aqueous Solutions ◽  
Anion Exchange ◽  
Hexavalent Chromium ◽  
Exchange Resin ◽  
Ph Value ◽  
Anion Exchange Resin ◽  
Freundlich Isotherm ◽  
Sorption Process ◽  
Isotherm Models ◽  
Exchange Resins

The removal of hexavalent chromium, Cr(VI), from aqueous solutions under different conditions using an anion-exchange resin (AXR) as an adsorbent was investigated under batch conditions. Such studies indicated that the percentage adsorption decreased with increasing initial Cr(VI) concentration, with the maximum removal of such ions occurred at a pH value of ca. 2.0. Both the Langmuir and Freundlich isotherm models were capable of reproducing the isotherms obtained experimentally. The sorption process was rapid during the first 20 min with equilibrium being attained within 30 min. The process followed first-order kinetics. The results demonstrate that such anion-exchange resins can be used for the efficient removal of Cr(VI) ions from water and wastewater.

Sign in / Sign up

Export Citation Format

Share Document