Application of ion-exchange resin beads to produce magnetic adsorbents

Abstract

Heavy metal ions are among the most dangerous contaminants, which can cause serious health problems. In this work, ion-exchange resin beads were used as supports for magnetite (Fe3O4) synthesis to produce heavy metal adsorbents which can be easily separated by magnetic field. The first step of the magnetite preparation was the replacement of hydrogen ions with Fe2+ and Fe3+ ions on the sulfonic acid groups of the resin. In the second step, magnetite particle formation was induced by coprecipitating the iron ions with sodium hydroxide. The regeneration of the ion-exchange resin was also carried out by using sodium hydroxide. SEM images verified that relatively large magnetite crystal particles (diameter = 100–150 nm) were created. The ion-exchange effect of the prepared magnetic adsorbent was also confirmed by applying Cu2+, Ni2+, Pb2+ and Cd2+ ions in adsorption experiments.

Polymeric and inorganic sorbents as a green option to recover critical raw materials at trace levels from sea saltwork bitterns

“…Considering the sulphonic sorbents structure and the mechanism suggested by Taha (2021), 75 Sikora et al (2021), 76 and Zhang et al (2022), 77 the suggested mechanisms for Co and Sr sorption are represented in reactions (15) and (16) depending on whether they are bonded to one or two functional groups. A similar mechanism to the one described in reaction (15) is expected for Cs and Rb (as Cs + and Rb + ) by the substitution of the Na + in the sorbent functional groups obtaining, in that case, a neutral molecule.…”

Beyond Freundlich and Langmuir: the Ruthven–virial equilibrium isotherm for aqueous-solid adsorption systems

“…The isotherm models evaluated in this study were fitted to literature data [tetracycline adsorption data (Ma et al 2022); nickel adsorption data (Sikora et al 2021)] using a nonlinear least-squares fitting algorithm to minimize the sum of squared residuals (SSR) defined by Eq. ( 8), where qi,obs is the ith observed value of q, qi,fit is the ith value of q calculated from a particular isotherm model, and z is the number of data points.…”

“…In this second example, the selected data set describes the adsorption of nickel ions by a magnetic ion exchanger (Sikora et al 2021). The adsorption isotherm, depicted in Fig.…”

“…The primary objective of the present study is to investigate the data fitting attributes of a slightly modified version of the exponential integral isotherm, called the Ruthven-virial isotherm. It is shown that the Ruthven-virial isotherm is highly competitive against both the Langmuir and Freundlich isotherms in correlating the experimental isotherms for tetracycline (Ma et al 2022) and nickel (Sikora et al 2021) adsorption on solid media. Furthermore, it is observed that the data fitting performance of the two-parameter Ruthven-virial isotherm is comparable to that of the three-parameter Sips isotherm.…”

A new polysaccharide-based ion-exchange resin for industrial wastewater treatment

“…In India ground water is used for domestic as well as agricultural purposes. Heavy metals ions such as iron, cobalt, cadmium, lead, mercury, chromium, selenium, arsenic, copper and zinc are invariably present in groundwater.These metal ions are considered to be toxins when they enter inside the body exceeding the prescribed limit, wherein they start causing illness [1][2][3]. Some of the heavy metal ions such as iron, cobalt, cadmium, lead, mercury, chromium, selenium and arsenic were found in industrial effluent of Okhla industrial area phase-II of Delhi NCR Region, India and because of this the groundwater of nearby areas is also contaminated [4].…”