scholarly journals Cobalt adsorption on the nano-hydroxyapatite matrix: isotherm and kinetic studies

2017 ◽  
Vol 65 (2) ◽  
pp. 131-137 ◽  
Author(s):  
V. N. Narwade ◽  
R. S. Khairnar
Keyword(s):  
Room Temperature ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Order Model ◽  
Nano Material ◽  
Pseudo Second Order ◽  
Wet Chemical ◽  
Wet Chemical Precipitation

Abstract Cobalt radionuclide is one of the prime contaminants generated during operation of pressurized heavy water. The paper reports the study of cobalt adsorption on hydroxyapatite (HAp) nanoceramic. A modified wet chemical precipitation method is used for HAp synthesis. The HAp nano-material is characterized by XRD, FTIR, TG/DTA, AFM, SEM, and EDAX. Experiments are performed in batches to observe the effect of cobalt adsorption on HAp matrix. The adsorption of cobalt on HAp is examined at room temperature. The isotherm and kinetic studies showed that the Freundlich isotherm and pseudo-second order model are the best choices to describe the nature of adsorption.

Synthesis and Structural Characterization of Zinc and Magnesium Doped Hydroxyapatite

2012 ◽  
Vol 531-532 ◽  
pp. 250-253 ◽  
Author(s):  
Hong Quan Zhang ◽  
Ming Zhang ◽  
Lu Wei Fu ◽  
Yu Ning Cheng
Keyword(s):  
Hydrothermal Treatment ◽  
Structural Characterization ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Starting Solution ◽  
Wet Chemical ◽  
Zn Ions ◽  
Wet Chemical Precipitation ◽  
Surface Of Crystals

Zn or Mg ions doped hydroxyapatite (HA) particles were successfully developed by introducing various concentration of Zn or Mg in the starting solution using wet chemical precipitation method and followed a hydrothermal treatment. The products were identified as HA by XRD and FTIR, and the precipitated particles had a rod-like morphology. All the products for Mg and Zn ions concentration in the preparation solution less than 40 mol% were identified as HA. Substitution of Mg and Zn in HA crystal would impair the crystallization of HA and significantly reduce the length of a, c values of HA unit cell, which clearly demonstrated that Mg or Zn ions were structurally incorporated into the apatite crystals, they were not just absorbed on the surface of crystals.

scholarly journals ADSORPTION AND KINETIC STUDIES OF A NATURAL DYE FROM CURCUMA LONGA L., ONTO BAMBOO YARN

2017 ◽  
Vol 2 (1) ◽  
pp. 13-26
Author(s):  
Tengku Khamanur Azma Tg. Mohd Zamri ◽  
Mimi Sakinah Abd Munaim ◽  
Zularisam Ab Wahid
Keyword(s):  
Adsorption Process ◽  
Regression Coefficient ◽  
Curcuma Longa ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Natural Dye ◽  
Isotherm Models ◽  
Order Model ◽  
Dyeing Process ◽  
Pseudo Second Order

Natural dye extracted from the rhizome of Curcuma longa L. were applied to bamboo yarns using exhaustion dyeing process. This study investigates the dyeing behaviour of Curcumin; the major color component isolated from rhizomes of Curcuma longa L.on bamboo yarn. Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich isotherm models were used to test the adsorption process of curcumin on bamboo yarn. Comparison of regression coefficient value indicated that the Freundlich isotherm most fitted to the adsorption of curcumin onto bamboo yarn. Furthermore, the kinetics study on this research fitted the pseudo-second order model which indicates that the basis of interaction was chemical adsorption.

scholarly journals Far-infrared optical constants of ZnO and ZnO/Ag nanostructures

RSC Advances ◽  
2014 ◽  
Vol 4 (40) ◽  
pp. 20902-20908 ◽  
Author(s):  
Reza Zamiri ◽  
Avito Rebelo ◽  
Golriz Zamiri ◽  
Atena Adnani ◽  
Ajay Kuashal ◽  
...  
Keyword(s):  
Optical Constants ◽  
Far Infrared ◽  
Cost Effective ◽  
Chemical Precipitation ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
Ag Nanoparticle ◽  
Wet Chemical ◽  
Wet Chemical Precipitation

We report on the synthesis of ZnO nanoplates and ZnO nanoplate/Ag nanoparticle heterostructures via a simple and cost effective wet chemical precipitation method.

Adsorptive removal of PPCPs by biomorphic HAP templated from cotton

2016 ◽  
Vol 74 (1) ◽  
pp. 276-286 ◽  
Author(s):  
Bin Huang ◽  
Dan Xiong ◽  
Tingting Zhao ◽  
Huan He ◽  
Xuejun Pan
Keyword(s):  
Adsorption Mechanism ◽  
Adsorption Process ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Precipitation Method ◽  
Adsorptive Removal ◽  
Transmission Electron ◽  
Initial Ph ◽  
Pseudo Second Order ◽  
Co Precipitation

Biomorphic nano-hydroxyapatite (HAP) was fabricated by a co-precipitation method using cotton as bio-templates and employed in adsorptive removal of ofloxacin (OFL) and triclosan (TCS) that are two representative pharmaceuticals and personal care products (PPCPs). The surface area and porosity, crystal phase, functional group, morphology and micro-structure of the synthesized HAP were characterized by Brunauer–Emmett–Teller isotherm, X-ray powder diffraction, Fourier transform infrared spectroscopy, scanning electron macroscopic and transmission electron microscopy. The effects of initial pH, ionic strength, initial concentration, contact time and temperature on the removal of PPCPs were studied in a batch experiment. The adsorption of OFL and TCS was rapid and almost accomplished within 50 min. Kinetic studies indicated that the adsorption process of OFL and TCS followed the pseudo-first-order and pseudo-second-order models, respectively. The Freundlich isotherm described the OFL adsorption process well but the adsorption of TCS fitted the Langmuir isotherm better. Thermodynamics and isotherm parameters suggested that both OFL and TCS adsorption were feasible and spontaneous. Hydrogen bond and Lewis acid–base reaction may be the dominating adsorption mechanism of OFL and TCS, respectively. Compared to other adsorbents, biomorphic HAP is environmentally friendly and has the advantages of high adsorption capacity, exhibiting potential application for PPCPs removal.

Removal of Pb (II) from Aqueous Solution by Blast-Furnace Slags

2013 ◽  
Vol 726-731 ◽  
pp. 2736-2741
Author(s):  
Ming Da Liu ◽  
Ge Tian ◽  
Liang Jie Zhao ◽  
Yao Sheng Wang ◽  
Lei Guo ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Blast Furnace ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Sorption Process ◽  
Second Order ◽  
Order Model ◽  
Pseudo Second Order ◽  
Solution Kinetic ◽  
Second Order Model

Five blast-furnace slags were used as adsorbents to remove Pb (II) from aqueous solution. Kinetic studies showed that the sorption process was best described by pseudo-second-order model. Among Langmuir, Freundlich and Temkin isotherms, the Freundlich isotherm had a better fit with the simulation of the adsorption of Pb (II).

scholarly journals Research on adsorption of Cd2+ by hydroxyapatite/chitosan nanocomposite

2021 ◽  
Vol 10 (2) ◽  
pp. 36-42
Author(s):  
Duyen Le Thi ◽  
Hanh Vo Thi ◽  
Dung Cong Tien ◽  
Thanh Dinh Thi Mai
Keyword(s):  
Experimental Data ◽  
Contact Time ◽  
Room Temperature ◽  
Acetic Acid Solution ◽  
Suitable Condition ◽  
Freundlich Isotherm ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Isotherm Models ◽  
Adsorption Efficiency

Hydroxyapatite/chitosan nanocomposite (n-HAp/ChS) was synthesized successfully from 0.5 M Ca(NO3)2 + 5 % chitosan/2 % acetic acid solution and 0.3 M (NH4)2HPO4 solution at pH 10-11 using 28 % NH3 solution by chemical precipitation method. n-HAp/ChS was used for the adsorption of Cd2+ from aqueous solution. The effect of factors on the Cd2+ adsorption efficiency and capacity was investigated. The adsorption efficiency and capacity obtained 97,75 % and 58,65 mg/g respectively at suitable condition: pH0 5.9,n-HAp/ChS mass of 0.1 g, initial Cd2+ concentration of 60 mg/L, contact time 40 minutes at room temperature (30oC). The experimental data was described by Langmuir and Freundlich isotherm models.

Sign in / Sign up

Export Citation Format

Share Document