Preparation of chelating fibrous polymer by different diamines and study on their physical and chemical properties

Abstract

The present work describes a new modification process for producing a chelating ion-exchanger fibers with a distinct selectivity for toxic heavy metal ions. Acrylic fibers were reacted with different diamine compounds in similar conditions. Modified acrylic fibers were prepared by partial conversion of the nitrile groups into amino groups under two-step processes. In the first step, the pure liquid diamine was mixed with the fibers and in the second step, water was gradually added to the reaction flask to reach a predetermined 3M concentration at refluxing temperature of 91 C. The aminated acrylic fibers (AAFs) were used as an ion adsorbent in a series of batch adsorption experiments for removal of chromium(III) and lead (II) ions.Experimental results showed that modified acrylic fiber with tetra methylene diamine (TMD) has the highest Pb(II) ion adsorption capacity. Results also showed aminated acrylic with ethylene diamine (EDA) has the most Cr(III) ion adsorption ability. Solubility tests showed, amination treatments give rise to the intermolecular crosslinkage in all samples. The Freundlich and Langmuir models simulated the adsorption equilibrium data of Cr(III) ions on modified fibers and their constants were determined.

Preconcentration and determination of Mercury(II) from natural water and milk sample by Histidine functionalized multi-walled carbon nanotubes (MWCNTs-His)

“…The metal ions adsorbed on the MWCNTS-HIS were then removed by placing 0.1 g of metal loaded MWCNTs-His in 10 ml of 1 M HNO3 solution for 30 min (Tahaei et al, 2008;Tuzen and Soyla, 2005).…”

“…Among different types of polymer adsorbent, polymer fibers have attracted great interest in recent years (Tahaei et al, 2008). This can be related to their structure and characteristics, like high specific surface, small cross-section, uniformity in diameter (in macroscopic scale) and long length of fiber to diameter (Abdouss and Mousavi-shoushtari, 2012).…”

“…Meanwhile, other investigators have successfully utilized these sorbents for quantitative extraction and monitoring trace amounts of lead (Tahaei et al, 2008). This paper describes the applications of multi-walled carbon nanotubes (MWCNTs-His) for selective extraction and solid phase pre-concentration of Hg(II) from aqueous and natural water samples.…”

Perconcentration of Ni(II) from Sample Water by Modified Nano Fiber

“…The metal ions adsorbed on the PANF-MMAwere then removed by placing 0.1 g of metal loaded fiber in 10 ml of 1M HNO 3 solution for 30 minutes 28 .…”

“…In our previous attempts, we modified SPE membrane disks with suitable compounds for selective determination of chromium [18][19]35 and lead 20 .Meanwhile, other investigators have successfully utilized these sorbents for quantitative extraction and monitoring trace amounts of lead [21][22][23] , copper [24][25][26] , silver [27][28] , mercury [29][30] , cadmium 31 , palladium 32 , Ce 33 and UO 2 34 .…”