β-Zeolite modified by ethylenediamine for sorption of Th(IV)

2017 ◽  
Vol 105 (6) ◽  
Author(s):  
Liu Peng ◽  
Wu Hanyu ◽  
Yuan Ni ◽  
Yin Zhuoxin ◽  
Pan Duoqiang ◽  
...  
Keyword(s):  
Steady State ◽  
Humic Acid ◽  
Ionic Strength ◽  
Contact Time ◽  
Surface Complexation ◽  
Sorption Isotherms ◽  
Ph Values ◽  
Β Zeolite ◽  
Batch Technique ◽  
Pseudo Second Order

Abstractβ-Zeolite-EDA was modified with ethylenediamine (EDA) after synthesized. The synthesized material was characterized and used for removal of Th(IV) from aqueous solutions. The influences of pH, ionic strength, contact time, temperature and humic acid (HA) on Th(IV) sorption onto synthesized β-zeolite-EDA was studied by batch technique. The dynamic process showed that the sorption of Th(IV) onto β-zeolite-EDA matched the pseudo-second-order kinetics model. The sorption of Th(IV) on β-zeolite-EDA was significantly dependent on pH values, the sorption percentage increased markedly at pH 3.5–4.5, and then maintained a steady state as pH values increased. Through simulating the sorption isotherms by Langmuir, Freundlich and Dubini–Radushkevich (D–R) models, it could be seen respectively that the sorption pattern of Th(IV) on β-zeolite-EDA was mainly controlled by surface complexation, and that the sorption processes was endothermic and spontaneous. The presence of HA increased Th(IV) sorption on β-zeolite-EDA.

Influence of soil humic acid and fulvic acid on sorption of thorium(IV) on MX-80 bentonite

2006 ◽  
Vol 94 (8) ◽  
Author(s):  
D. Xu ◽  
X. K. Wang ◽  
C. L. Chen ◽  
X. Zhou ◽  
X. L. Tan
Keyword(s):  
Humic Acid ◽  
Fulvic Acid ◽  
Sorption Isotherms ◽  
Positive Influence ◽  
Low Ph ◽  
Ph Values ◽  
Batch Technique ◽  
Soil Humic Acid ◽  
Drastic Effect ◽  
Chemical Analogue

SummaryTh(IV) is considered herein as a chemical analogue of other actinides (IV). Effect of pH, ionic strength and humic acid/fulvic acid concentrations on the sorption of thorium(IV) to MX-80 bentonite was studied by batch technique. The sorption isotherms were acquired by varying pH in the range of 0.5–12 and FA/HA concentration in the range of 2–20 mg/L. The results indicate that soil fulvic acid has higher carboxylic content than humic acid, and has stronger positive influence on the sorption of Th(IV) on bentonite at low pH values than humic acid. The increase of FA/HA concentration results in a slight increase of Th(IV) sorption on FA/HA coated bentonite. The results of no drastic effect of different addition sequences of FA/HA and Th(IV) to bentonite suspension on Th(IV) sorption in the ternary system HA/FA-Th(IV)-bentonite indicate that both the Th(IV)-HA/FA complexation and HA/FA-bentonite sorption do not affect the sorption of Th(IV) on HA/FA coated bentonite obviously. The samples were also measured by SEM method and the results show that the surface properties of different samples are different.

Adsorption behavior of Th(IV) onto illite: Effect of contact time, pH value, ionic strength, humic acid and temperature

2016 ◽  
Vol 127-128 ◽  
pp. 35-43 ◽  
Author(s):  
Zhang Hongxia ◽  
Wang Xiaoyun ◽  
Liang Honghong ◽  
Tan Tianshe ◽  
Wu Wangsuo
Keyword(s):  
Humic Acid ◽  
Ionic Strength ◽  
Contact Time ◽  
Ph Value ◽  
Adsorption Behavior

Disinfection performance of nanosilver and impacts of environmental conditions on viral inactivation by nanosilver

2013 ◽  
Vol 14 (1) ◽  
pp. 150-157 ◽  
Author(s):  
Yang Xu ◽  
Xiaona Chu ◽  
Jiangyong Hu ◽  
Say Leong Ong
Keyword(s):  
Escherichia Coli ◽  
Silver Nanoparticles ◽  
Humic Acid ◽  
Ionic Strength ◽  
Environmental Conditions ◽  
Contact Time ◽  
Chloride Ion ◽  
Viral Inactivation ◽  
E Coli ◽  
High Concentrations

Three types of nanosilver materials, which were commercial, chemically-synthesized and biologically-synthesized, respectively, were compared in terms of the disinfection efficiencies against Escherichia coli and MS2 coliphage in order to pinpoint promising material with the best performance. Disinfection results showed biologically-synthesized silver nanoparticles (referred to hereafter as ‘bio-AgNPs’) had the best disinfection performance, 10 mg/L of which was able to inactivate all the E. coli in 1 min (>6 log removals) and achieved 4 log removals of MS2 coliphage. Bio-AgNPs were therefore selected for further study in terms of effects of the concentration and contact time as well as the impacts of environmental conditions on the viral inactivation. Given the viral inactivation profile of bio-AgNPs shown in this study, it could be concluded that viral inactivation by bio-AgNPs could be inhibited by total organic carbon (TOC) (10 mg/L as humic acid) and chloride ion (5 mg/L) to a large extent while Ca2+/Mg2+/ionic strength only had minor effects on the viral inactivation at high concentrations (188 mg/L as CaCO3 of hardness or 5.6 mM of ionic strength, respectively). This part of the study may help enlighten further mechanism studies on viral inactivation by nanosilver.

scholarly journals Adsorption Of Cd(II) Ions From Aqueous Solution By A Low-Cost Biosorbent Prepared From Ipomea Pes-Caprae Stem

2020 ◽  
Vol 9 (3) ◽  
pp. 197-206
Author(s):  
Thaharah Ramadhani ◽  
Faisal Abdullah ◽  
Indra Indra ◽  
Abrar Muslim ◽  
Suhendrayatna Suhendrayatna ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Optimal Condition ◽  
Adsorption Capacity ◽  
Contact Time ◽  
Low Cost ◽  
Ph Values ◽  
Monolayer Adsorption ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Ft Ir

The use of a low-cost biosorbent prepared from Ipomoea pes-caprae stem for the adsorption of Cd(II) ions from aqueous solution at different contact times, biosorbent sizes, pH values, and initial Cd(II) ions concentration solution was investigated. The biosorbent was analyzed using Fourier-transform infrared spectroscopy (FT-IR) to find important IR-active functional groups. A scanning electron microscope (SEM) was used to examine the biosorbent morphology. The experimental results showed the highest Cd(II) ions adsorption was 29.513 mg/g  under an optimal condition as initial Cd(II) ions concentration of 662.77 mg/L, 1 g dose, 80-min contact time, pH 5, 75 rpm of stirring speed, 1 atm, and 30 oC. Cd(II) ions' adsorption kinetics obeys the linearized pseudo-second-order kinetics (R2 = 0.996), and the adsorption capacity is based on the optimal condition, and the rate attained was 44.444 mg/g and 0.097 g/mg. Min, respectively. Besides, the adsorption isotherms were very well fitted by the linearized Langmuir isotherm model, and the monolayer adsorption capacity and pore volume determined was 30.121 mg/g and 0.129 L/mg, respectively. These results indicated the chemisorption nature

Sorption of Uranium (VI) From Aqueous Solution Using Nanomagnetite Particles; Singly and Coated With Humic Acid

2021 ◽  
Author(s):  
Ismail Mohamed Ahmed ◽  
Aly A. Helal ◽  
Rasha Gamal ◽  
Salah aboEinien ◽  
Abdullah A. Helal
Keyword(s):  
Aqueous Solution ◽  
Humic Acid ◽  
Magnetite Nanoparticles ◽  
Kinetic Data ◽  
Contact Time ◽  
Organic Coating ◽  
Langmuir Model ◽  
Sorption Kinetic ◽  
Maximum Capacity ◽  
Pseudo Second Order

Abstract Magnetite nanoparticles (Fe3O4) and humic acid coated magnetite nanoparticles (Fe3O4/HA) were investigated for the removal of U(VI) from aqueous solution. Batch sorption experiments were studied as a function contact time, adsorbent mass, U(VI) concentration and pH. The sorption kinetic data follow the pseudo-second order while the isotherms are found to obey Langmuir model with maximum capacity (Qmax) of 230, 196 mg/g for Fe3O4 and Fe3O4/HA, respectively. The study reveals that humic acid decreases the sorption capacity due to the formation of a polyanionic organic coating and thus altering the surface properties of the particles and reduces the magnetite aggregation and stabilizes the magnetite suspension.

Adsorption of Zn(II) from Aqueous Solution by Attapulgite

2014 ◽  
Vol 692 ◽  
pp. 149-155 ◽  
Author(s):  
Jun Ren ◽  
Dan Xu ◽  
Ling Tao ◽  
Zhao Wen Fu
Keyword(s):  
Aqueous Solution ◽  
Ionic Strength ◽  
Contact Time ◽  
Langmuir Adsorption Isotherm ◽  
Maximum Adsorption Capacity ◽  
Order Process ◽  
Langmuir Adsorption ◽  
Pseudo Second Order ◽  
Adsorbent Dose ◽  
Second Order Process

The adsorption behavior of Zn (II) by attapulgite were studied in the paper, The effects of adsorbent dose. Contact time, ionic strength and temperature on the adsorption were investigated. The maximum adsorption capacity is 4.129 mg.g-1 at 333 K. The kinetic study indicated that the adsorption was a pseudo-second-order process. The adsorption was well fitted by the Langmuir adsorption isotherm model. The results indicated that the sorption of Zn (II) by attapulgite was a spontaneous process, and the sorption was endothermic.

Bentonite for ciprofloxacin removal from aqueous solution

2013 ◽  
Vol 68 (4) ◽  
pp. 848-855 ◽  
Author(s):  
Nevim Genç ◽  
Esra Can Dogan ◽  
Meral Yurtsever
Keyword(s):  
Aqueous Solution ◽  
Ionic Strength ◽  
Contact Time ◽  
Aqueous Solubility ◽  
Agitation Speed ◽  
Soil System ◽  
Adsorbent Dosage ◽  
Fluoroquinolone Antibiotics ◽  
Isotherm Adsorption ◽  
Pseudo Second Order

Ciprofloxacin hydrochloride (CIP) is the second generation of fluoroquinolone antibiotics whose residues are found in wastewater and surface water. CIP has high aqueous solubility under different pH conditions and high stability in the soil system. In this study, bentonite was used as a potential sorbent for the removal of CIP from aqueous solutions using batch experiments. The effects of various parameters such as contact time, pH, adsorbent dosage, agitation speed, ionic strength and initial concentration of CIP in aqueous solution on the adsorption capacity were investigated. The optimum contact time, pH, agitation speed and adsorbent dosage were found to be 30 min, 4.5 pH, 150 rpm and 2.5 g L−1, respectively. When the ionic strength was increased from 5 to 50 mM, the adsorption of CIP decreased from 97.8 to 93.4%. The isotherm adsorption data fitted well with the Langmuir model, Kl and qe were found to be 0.27 L mg−1 and 147.06 mg g−1, and the data fitted well with the pseudo-second order kinetics, whereby k was found to be 2.19 g mg−1 h−1.

scholarly journals Effect of Water Chemistry on the Uptake of Co(II) on Graphene Oxide Investigated by Batch Technique

2021 ◽  
Vol 20 (3) ◽  
Author(s):  
X. Tang ◽  
J. Luo ◽  
L. Wang ◽  
X. Li
Keyword(s):  
Graphene Oxide ◽  
Ionic Strength ◽  
Kinetic Studies ◽  
Inhibitory Effect ◽  
Order Kinetic ◽  
Temperature Dependent ◽  
Environmental Application ◽  
Batch Technique ◽  
Order Kinetic Model ◽  
Pseudo Second Order

The uptake of Co(II) on graphene oxide (GO) by an adsorption process as a function of pH and ionic strength in the absence and presence of humic acid (HA) or fulvic acid (FA) was studied using batch technique. The results indicated that the uptake is strongly dependent on pH but independent of ionic strength. A stimulative effect of HA/FA on Co(II) uptake was found at pH < 7.0, whereas an inhibitory effect was observed at pH > 7.0. Kinetic studies suggest that Co(II) uptake on GO could be described more favorably by the pseudo-second-order kinetic model. The uptake isotherms can be described better by the Langmuir, Freundlich, and D-R models than by the linear model. The thermodynamic data calculated from the temperature-dependent uptake isotherms suggests that the uptake of Co(II) on GO is spontaneous and endothermic. Results of this work are of great importance for the environmental application of GO in the treatment of Co(II) from wastewater and indicated that GO is promising for the natural attenuation of Co(II) and related metal ions from aqueous solution.

scholarly journals Cadmium and Lead Adsorption Capacities of Nigerian Ultisol Soil of Tropics

2019 ◽  
Vol 35 (3) ◽  
pp. 1004-1012 ◽  
Author(s):  
Henry Olumayowa Oluwasola ◽  
Jonnie Niyi Asegbeloyin ◽  
Alfred Ezinna Ochonogor ◽  
Julius Udeh Ani ◽  
Collins Ugochukwu Ibeji ◽  
...  
Keyword(s):  
Contact Time ◽  
Adsorption Process ◽  
Sorption Process ◽  
Maximum Adsorption Capacity ◽  
Lead Adsorption ◽  
Adsorption Capacities ◽  
Batch Technique ◽  
Pseudo Second Order ◽  
Cadmium And Lead ◽  
Kinetics Of

The study investigates the sorption of cadmium (Cd) and lead (Pb) by Nsukka urban soils, a Nigeria soil classified as an ultisol soil of tropics. Laboratory batch technique was utilized to investigate the effect of pH, temperature, contact time, and concentration on the adsorption process. Results showed that adsorption efficiency of the soils for Cd2+ and Pb2+ increased with increase in pH, temperature, and contact time but decreased with increase in concentration. The data from adsorption study was fitted to the Langmuir, Freundlich and Temkin adsorption isotherms, and results revealed that Langmuir isotherm fitted most satisfactorily. On the basis of the obtained maximum adsorption capacity (qmax) from the Langmuir model, the affinity of Cd and Pb for the studied soil was Pb2+ > Cd2+. Pseudo-second order (r2 ≥ 0.995-0.999) best described the kinetics of the sorption process for the metal ions in the soil.

scholarly journals Characterization and Pb(II) removal potential of corn straw- and municipal sludge-derived biochars

2017 ◽  
Vol 4 (9) ◽  
pp. 170402 ◽  
Author(s):  
Shujuan Wang ◽  
Wei Guo ◽  
Fan Gao ◽  
Rui Yang
Keyword(s):  
Aqueous Solutions ◽  
Surface Complexation ◽  
Order Kinetic ◽  
Municipal Sludge ◽  
Corn Straw ◽  
Ph Values ◽  
Adsorption Capacities ◽  
Adsorption Data ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Corn straw- and municipal sludge-derived biochars (CS-BC and MS-BC, respectively) were used to remove Pb(II) from aqueous solutions. Despite being pyrolysed at the same temperature (723 K), MS-BC showed higher porosity and hydrophobicity than CS-BC. The optimum biochar loading and pH values allowing efficient Pb(II) removal (greater than 80%) were 0.2 g l −1 and 7.0, respectively. The presence of PO 4 3− (greater than 0.01 mol l −1 ) significantly affected the adsorptive performance of Pb(II) on the biochar samples. The adsorption data fitted well to a pseudo-second-order kinetic model and a Langmuir model, and the maximum Pb(II) adsorption capacities were 352 and 387 mg g −1 for CS-BC and MS-BC, respectively. The main mechanisms involved in the adsorption of Pb(II) on biochar were electrostatic attraction and surface complexation. When comparing both biochars, CS-BC showed better cost-effectiveness for the removal of Pb(II) from aqueous solutions.

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