scholarly journals Determination Of Interactions Of Ferrihydrite-Humic Acid-Pb(II) System

2021 ◽  
Author(s):  
Zhuanjun Zhao ◽  
Liwei Yao ◽  
Jie Li ◽  
Xiangbang Ma ◽  
Liangwei Han ◽  
...  
Keyword(s):  
Humic Acid ◽  
Mössbauer Spectra ◽  
High Efficiency ◽  
Adsorption Property ◽  
Freundlich Isotherm ◽  
Sorption Kinetics ◽  
Lead Uptake ◽  
Ph Change ◽  
Mossbauer Spectra

Abstract Ferrihydrite often precipitates with humic acid in natural ways, affecting the fate of lead ions, the stabilization of humic acid and the aging process of ferrihydrite. A series of 2-line ferrihydrite-humic (Fh-HA) acid with varying C loadings has been prepared, the morphology and surface properties of Fh-HA organo-minerals have been characterized, the adsorption property of Pb ions onto Fh-HA has been studied. The results indicated a strong interference of HA to ferrihydrite. 2-line Fh dominated mineral phase in all samples, but with increasing C/Fe molar ratios the crystallinity gradually weakened, particles became smaller and SSA decreased significantly. The data of Mössbauer spectra confirmed C loading changed the unit structure of ferrihydrite. Fh-HA performed good adsorption properties to Pb(Ⅱ): high efficiency and big capacity, especially Fh-HA_2.0. pH had great effect on Lead uptake, the pH change not only affects the amounts of competitive ions in solutions, but also the dissociation and protonation of functional groups on the surface of Fh-HA. Sorption kinetics can be well modeled by a pseudo-second order model, and the process was controlled by film and intraparticle adsorption simultaneously. The adsorption isotherms can be well described by Freundlich isotherm model. The careful determination of Fe 2p, O 1s and Pb 4f spectra before and after lead adsorption showed mononuclear bidentate or binuclear bidentate ligands occurring on Fh-HA surface, forming stable inner-sphere complex. By comparison of Mössbauer spectra and TEM images, it revealed a slower evolution of iron oxide/oxyhydroxide phases in Fh-HA-Pb system compared to pure ferrihydrite with aging time, ferrihydrite transformed to a combination of ferrihydrite, goethite and hematite phases. in this study, the determination of C-Fe interaction, Pb fate influenced by Fh-HA and transformation of ferrihydrite would have a great implication to application of Fh-HA precipitates in remediation for soil or groundwater polluted by heavy metals.

scholarly journals Use of aminated hulls of sunflower seeds for the removal of anionic dyes from aqueous solutions

2019 ◽  
Vol 17 (3) ◽  
pp. 1211-1224 ◽  
Author(s):  
T. Jóźwiak ◽  
U. Filipkowska ◽  
S. Brym ◽  
L. Kopeć
Keyword(s):  
Sorption Capacity ◽  
Textile Industry ◽  
Sunflower Seed ◽  
Freundlich Isotherm ◽  
Sorption Kinetics ◽  
Reactive Black 5 ◽  
Anionic Dyes ◽  
Maximum Sorption Capacity ◽  
Maximum Sorption

Abstract In this study, we analyzed the effectiveness of sorption of dyes popular in the textile industry (Reactive Black 5, Reactive Yellow 84, Acid Yellow 23, and Acid Red 18) on aminated and non-aminated seed hulls of common sunflower (Helianthus annuus L.). The scope of the study included: determination of the effect of pH on dye sorption effectiveness, sorption kinetics analyses (sorption equilibrium time, pseudo-first-order/pseudo-second-order model, intramolecular diffusion model), and determination of the maximum sorption capacity against dyes (Langmuir/Freundlich isotherm). The sorbent was subjected to the FTIR analysis. The sorption capacity of the aminated sunflower seed hulls against reactive dyes RB5 and RY84 accounted for 51.02 mg/g and 63.27 mg/g, respectively, and was higher by 1665% (17.6 times higher) and 1425% (15.3 times higher) compared to that of non-modified hulls. In the case of acidic dyes, Acid Yellow 23 and Acid Red 18, the sorption capacity of the aminated sunflower seed hulls reached 44.78 mg/g and 42.19 mg/g, respectively, and was higher by 1881% (19.8 times higher) and 2284% (23.8 times higher), respectively, compared to the non-modified hulls.

scholarly journals The influence of ozonation on the activated carbon adsorption of phenol and humic acid

2007 ◽  
Vol 9 (4) ◽  
pp. 107-110 ◽  
Author(s):  
Bożena Seredyńska-Sobecka ◽  
Maria Tomaszewska
Keyword(s):  
Activated Carbon ◽  
Humic Acid ◽  
Oxygen Demand ◽  
Freundlich Isotherm ◽  
Model Solution ◽  
Activated Carbon Adsorption ◽  
Phenol Adsorption ◽  
Isotherm Equation ◽  
Carbon Adsorption

The influence of ozonation on the activated carbon adsorption of phenol and humic acid To study the influence of ozonation on the activated carbon adsorption, a model solution containing approximately 8 mg/dm3 of humic acid and approximately 1 mg/dm3 of phenol has been ozonated, and then adsorption kintetics and adsorption isotherm experiments have been performed. The applied ozone doses ranged from 1 to 3 mg O3/dm3, and a contact time was 1 min. In the adsorption experiments, the commercial activated carbon CWZ-30 (Gryfskand Sp. z o.o., Hajnówka, Poland) has been used. Phenol adsorption under equilibrium conditions was determined by the Freundlich isotherm equation, and the modified Freudlich isotherm equation has been employed for the determination of humic acid equilibrium adsorption. The applied oxidation conditions resulted in color, chemical oxygen demand (COD), total organic carbon (TOC) and UV254 absorbance removal, by 4 - 13%, 3 - 6%, 3 - 7%, respectively. After ozonation, phenol concentration decreased by 6 - 23%. These changes in the model solution did not affect the humic acid adsorption, however, they deteriorated phenol adsorption.

Synthese, Struktur und Sb-Mößbauer-Spektren kovalenter und ionischer Tetraorganoantimon(V) -Verbindungen / Synthesis, Structure and Sb-Mößbauer Spectra of Covalent and Ionic Tetraorganoantimony(V) Compounds

1983 ◽  
Vol 38 (11) ◽  
pp. 1477-1483 ◽  
Author(s):  
Hubert Schmidbaur ◽  
Beatrix Milewski-Mahrla ◽  
Fritz E. Wagner
Keyword(s):  
Crystal Structure ◽  
Structure Determination ◽  
Anthranilic Acid ◽  
Mössbauer Spectra ◽  
Crystal Structure Determination ◽  
Mossbauer Spectra

AbstractTetramethylstibonium and tetraphenylstibonium oxinate(1, 2) and anthranilate (4, 5) have been prepared from the antimony pentaorganyls and 8-oxy-quinoline or anthranilic acid, respectively. The crystal structure determination of 1 revealed covalent molecules with planar bidentate oxinate as part of a distorted coordination octahedron at antimony. -121Sb-Mößbauer spectra of 1, 2, 4, 5 and of tetramethylstibonium acetylacetonate (3) are also in agreement with covalent structures, but a pentacoordinate environment of Sb is more likely for the anthranilates 4, 5. The spectra of the hydrogendicarboxylates 6-9, however, point to ionic stuctures with, if any, only weak donor interactions of the anions with the stibonium cations.

The determination of θ=(Vzz, H) from Mössbauer spectra

1978 ◽  
Vol 157 (1) ◽  
pp. 127-129 ◽  
Author(s):  
Gérard Le Caër ◽  
Jean-Marie Dubois ◽  
Lennart Häggström ◽  
Tore Ericsson
Keyword(s):  
Mössbauer Spectra ◽  
Mossbauer Spectra

Donor Atom Set and Spin State of Iron(II). Bis(ligand)iron(II) and Bis(ligand)nickel(II) Complexes of 2,2′-Bipyridine-6-carbothioamide and 2,2′-Bipyridine-6-carboxamide

1998 ◽  
Vol 51 (4) ◽  
pp. 273 ◽  
Author(s):  
Bradley J. Childs ◽  
John M. Cadogan ◽  
Donald C. Craig ◽  
Marcia L. Scudder ◽  
Harold A. Goodwin
Keyword(s):  
Ground State ◽  
Mössbauer Spectra ◽  
Monoclinic Space Group ◽  
Singlet Ground State ◽  
Orthorhombic Space Group ◽  
Triclinic Space Group ◽  
Space Group ◽  
Mossbauer Spectra ◽  
Infrared Spectral

2,2′-Bipyridine-6-carbothioamide (bpytm) and 2,2′-bipyridine-6-carboxamide (bpyam) are NNS and NNO donors, respectively, in their cationic bis(ligand)iron(II) and bis(ligand)nickel(II) complexes. The former ligand provides the stronger field and salts of [Fe(bpytm)2]2+ have a singlet ground state, while those of [Fe(bpyam)2]2+ have a quintet ground state. The magnetism and the electronic and Mössbauer spectra of salts of these cations have been measured. The low-temperature Mössbauer spectra of iron(II) complex salts of the carboxamide indicate, for the perchlorate and triflate salts, but not for the fluoroborate salt, a partial transition to singlet-state species. The mode of coordination of the ligands is indicated by infrared spectral data and has been confirmed by determination of the structures of [Ni(bpytm)2] Cl2.4H2O, [Ni(bpyam)2] [BF4]2.H2O and [Fe(bpyam)2] [BF4]2. In addition, the structures of the free ligands have been determined. Hydrogen bonding is present in the free ligands and their complexes. 2,2′-Bipyridine-6-carbothioamide: monoclinic, space group P21/c, a 8·265(3), b 11·175(2), c 11·114(4) Å, β 94·47(2)°, Z 4. 2,2′-Bipyridine-6-carboxamide: monoclinic, space group P21/c, a 13·581(2), b 9·926(1), c 16·824(3) Å, β 116·481(7)°, Z 8. [Ni(bpytm)2] Cl2.4H2O: triclinic, space group P-1, a 9·291(5), b 12·426(7), c 13·425(7) Å, α 113·54(3), β 95·63(3), γ 94·43(3)°, Z 2. [Ni(bpyam)2][BF4]2.H2O: triclinic, space group P-1, a 10·663(5), b 10·861(6), c 12·799(6) Å, α 68·70(4), β 77·84(4), γ 78·47(4)°, Z 2. [Fe(bpyam)2] [BF4]2: orthorhombic, space group P bcn, a 12¡317(6), B 12¡609(4), c 16·644(8) Å, Z 4.

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