Biosorption of Chromium Ions by Calcium Alginate Nanoparticles

Abstract

The objectives of the present work include synthesis of nanoparticles of calcium alginate by emulsion crosslinking method, their characterization by techniques such as FTIR, scanning electron microscopy (SEM), XRD, particle size and surface charge analysis, and study of removal of chromium ions from synthetic aqueous solutions. In order to study the effect of various factors like adsorbent dose, initial metal ion concentration, pH and temperature on the adsorption of chromium ions from water, a series of batch sorption experiments were conducted. The obtained results were analysed by Langmuir and Freundlich isotherm models and it was found that the adsorption of chromium more precisely follows Langmuir absorption isotherm. The metal ion removal capacity of the nanoparticles was found to depend on the chemical composition of the adsorbent, concentration of the metal ion solution, pH and temperature of the medium and speed of the suspension from wastewater before disposal.

Analysis of the Degradation Process of Alginate-Based Hydrogels in Artificial Urine for Use as a Bioresorbable Material in the Treatment of Urethral Injuries

“…The absorbance in the range 3000 to 3500 cm −1 , characteristic for the stretching of hydroxyl bonds (O-H), was the highest for samples crosslinked with calcium ions. Tensile vibration bands of symmetrical and asymmetrical CO carboxyl bonds and divalent ions were observed at values ranging from 1400 to 1600 cm −1 , while bands from 1000 to 1200 cm −1 characteristic for C-O bond vibration, at 800 cm −1 characteristic for mannuronic acid, and at 700 cm −1 characteristic for guluronic acid were also observed upon binding crosslinking ions [32,33]. of the results obtained could be achieved by conducting clinical trials using the proposed materials in the form of a urethra stent.…”

Isothermal Modelling of the Adsorption of Chromium onto Calcium Alginate Nanoparticles

“…The equilibrium data from [23] was analyzed using ten models-Henry, Langmuir, Dubinin-Radushkevich, Freundlich, BET, Toth, Sips, Fritz-Schlunder IV, Baudu and Fritz-Schlunder V, and fitted using non-linear regression. Only the Toth and Frtz-Schlunder V models cannot fit the data (Figs.…”

“…Data from Figure 1 from a published work [23] were digitized using the software Webplotdigitizer 2.5 [39]. The data were then nonlinearly regressed using the curve-fitting software CurveExpert Professional software (Version 1.6).…”

“…Chromium in the cryochromate (CrO4 2-) and dichromate (Cr2O7 2-) forms is more toxic than chromium in other valence states [20]. When selecting an adsorbent for the removal of dangerous metal ions, it is important to consider both traditional and non-conventional materials [9,[21][22][23][24] including nanomaterials. The sorption of chromium ions onto nanoparticles have been attempted before using silicon and iron nanoparticles [25][26][27].…”

Sequestration of Sulfate Anions from Groundwater by Biopolymer-Metal Composite Materials

“…The IR spectrum of sodium alginate has a characteristic -OH stretching band at 3480 cm −1 , C-H stretching vibrations at 2927 cm −1 and asymmetric stretching vibration for -COOH at 1648 cm −1 . The bands at 1306 and 1426 cm −1 relate to symmetric C-O stretching of the carboxyl groups, whereas the IR bands at 937 and 1104 cm −1 were assigned to elongation of C-O groups [63][64][65]. Upon composite formation, the C=O stretching and bending bands exhibit broadening along with a shift to lower wavenumber values, respectively.…”