Adsorption of Rhodamine B from an aqueous solution by acrylic-acid-modified walnut shells: characterization, kinetics, and thermodynamics

A series of porphyrin triads (1–6), based on the reaction of trans-dihydroxo-[5,15-bis(3-pyridyl)-10,20-bis(phenyl)porphyrinato]tin(IV) (SnP) with six different phenoxy Zn(II)-porphyrins (ZnLn), was synthesized. The cooperative metal–ligand coordination of 3-pyridyl nitrogens in the SnP with the phenoxy Zn(II)-porphyrins, followed by the self-assembly process, leads to the formation of nanostructures. The red-shifts and remarkable broadening of the absorption bands in the UV–vis spectra for the triads in CHCl3 indicate that nanoaggregates may be produced in the self-assembly process of these triads. The emission intensities of the triads were also significantly reduced due to the aggregation. Microscopic analyses of the nanostructures of the triads reveal differences due to the different substituents on the axial Zn(II)-porphyrin moieties. All these nanomaterials exhibited efficient photocatalytic performances in the degradation of rhodamine B (RhB) dye under visible light irradiation, and the degradation efficiencies of RhB in aqueous solution were observed to be 72~95% within 4 h. In addition, the efficiency of the catalyst was not impaired, showing excellent recyclability even after being applied for the degradation of RhB in up to five cycles.

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Thermo-Responsive Behavior of Mixed Aqueous Solution of Hydrophilic Polymer with Pendant Phosphorylcholine Group and Poly(Acrylic Acid)

Polymers ◽

10.3390/polym13010148 ◽

2021 ◽

Vol 13 (1) ◽

pp. 148

Author(s):

Hirokazu Fukumoto ◽

Kazuhiko Ishihara ◽

Shin-Ichi Yusa

Keyword(s):

Aqueous Solution ◽

Acrylic Acid ◽

Solution Temperature ◽

Interpolymer Complex ◽

Mixed Aqueous Solution ◽

Upper Critical Solution Temperature ◽

Acidic Conditions ◽

Decreasing Ph ◽

Increasing Temperature ◽

Poly Acrylic Acid

A mixed aqueous solution of hydrophilic poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and poly(acrylic acid) (PAAc) becomes cloudy under acidic conditions at room temperature. The pendant carboxylic acid groups in PAAc form hydrogen bonds with the ester and phosphate groups in PMPC. While the polymers aggregate under acidic conditions, neither one associate under basic conditions because of the deprotonation of the pendant carboxy groups in PAAc. We observed that the interpolymer complex formed from PMPC, and PAAc was dissociated in aqueous solutions with increasing temperature, which is an upper critical solution temperature behavior. With increasing temperature, the molecular motion increased to dissociate the interpolymer complex. The phase transition temperature increased with increasing polymer and salt concentrations, and with decreasing pH.

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Adsorptive removal of Rhodamine B dye from aqueous solution by using graphene–based nickel nanocomposite

Heliyon ◽

10.1016/j.heliyon.2021.e06851 ◽

2021 ◽

Vol 7 (4) ◽

pp. e06851

Author(s):

Usha Jinendra ◽

Dinesh Bilehal ◽

B.M. Nagabhushana ◽

Avvaru Praveen Kumar

Keyword(s):

Aqueous Solution ◽

Rhodamine B ◽

Adsorptive Removal ◽

Rhodamine B Dye

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Determination of the complexation properties of a crosslinked poly(acrylic acid) gel with copper(II), nickel(II), and lead(II) in dilute aqueous solution

Canadian Journal of Chemistry ◽

10.1139/v01-059 ◽

2001 ◽

Vol 79 (4) ◽

pp. 370-376 ◽

Cited By ~ 5

Author(s):

Catherine Morlay ◽

Yolande Mouginot ◽

Monique Cromer ◽

Olivier Vittori

Keyword(s):

Aqueous Solution ◽

Ionic Strength ◽

Acrylic Acid ◽

Metal Ion ◽

Conditional Stability ◽

Binding Properties ◽

Complex Species ◽

Complexing Capacity ◽

Dilute Aqueous Solution ◽

Poly Acrylic Acid

The possible removal of copper(II), nickel(II), or lead(II) by an insoluble crosslinked poly(acrylic acid) was investigated in dilute aqueous solution. The binding properties of the polymer were examined at pH = 6.0 or 4.0 with an ionic strength of the medium µ = 0.1 or 1.0 M (NaNO3) using differential pulse polarography as an investigation means. The highest complexing capacity of the polyacid was obtained with lead(II) at pH = 6.0 with µ = 0.1 M, 4.8 mmol Pb(II)/g polymer. The conditional stability constants of the complex species formed were determined using the method proposed by Ruzic assuming that only the 1:1 complex species was formed; for lead(II) at pH = 6.0 and µ = 0.1 M, log K' = 5.3 ± 0.2. It appeared that the binding properties of the polymer increased, depending on the metal ion, in the following order: Ni(II) < Cu(II) < Pb(II). The complexing capacity and log K' values decreased with the pH or with an increase of the ionic strength. These results were in agreement with the conclusions of our previous studies of the hydrosoluble linear analogues. Finally, with the insoluble polymer, the log K' values were comparable to those previously obtained with the linear analogue whereas the complexing capacity values expressed in mmol g-1 were slightly lower.Key words: insoluble crosslinked poly(acrylic acid), copper(II), nickel(II), and lead(II) complexation.

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