scholarly journals Preparation of Synthetic Clays to Remove Phosphates and Ibuprofen in Water

Water ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 2394
Author(s):  
Rosa Devesa-Rey ◽  
Jesús del Val ◽  
Jorge Feijoo ◽  
José González-Coma ◽  
Gonzalo Castiñeira ◽  
...  

The main objective of this study consists in the synthesis of a layered double hydroxide (LDH) clay doped with magnesium and aluminum in order to test the removal of phosphates and ibuprofen in water. Two different LDH composites are assessed: oven-dried (LDHD) and calcined (LDHC). Single adsorptions of phosphate and ibuprofen showed up to 70% and 58% removal in water, when LDHC was used. A poorer performance was observed for LDHD, which presented adsorption efficiencies of 52% and 35%, respectively. The simultaneous removal of phosphate and ibuprofen in water showed that LDHC allows a greater reduction in the concentration of both compounds than LDHD. Phosphate adsorption showed a close agreement between the experimental and theoretical capacities predicted by the pseudo-second-order model, whereas ibuprofen fitted to a first-order model. In addition, phosphate adsorption showed a good fit to an intraparticle diffusion model and to Bangham model suggesting that diffusion into pores controls the adsorption process. No other mechanisms may be involved in ibuprofen adsorption, apart from intraparticle diffusion. Finally, phosphate desorption could recover up to 59% of the initial concentration, showing the feasibility of the recuperation of this compound in the LDH.

2013 ◽  
Vol 726-731 ◽  
pp. 733-738 ◽  
Author(s):  
Ling Die Meng ◽  
Min Wu ◽  
Ye Tian ◽  
Shigenori Kuga ◽  
Yong Huang

This work reports a cationic modified cellulose hydrogel for fluoride and arsenic adsorption. This adsorbent had a high efficiency in removal of F-, AsO2- and AsO43- simultaneously from aqueous solutions, even at low initial concentrations. Adsorption kinetics showed the relatively rapid rate to reach equilibrium, as could be explained by the pseudo-second-order model and the intraparticle diffusion model within 20 min before the equilibrium. Freundlich model could fit the adsorption process best, and the results showed the improved arsenic adsorption performances especially for AsO43-, much larger than other reported absorbents.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Faranak Pishgar ◽  
Homayon Ahmad Panahi ◽  
Ali Akbar Khodaparast Haghi ◽  
Vahid Motaghitalab ◽  
Amir Hesam Hasani

Diazinon and chlorpyrifos are two common organophosphorus poisons to fight the pests in Iran. The removal of these poisons from water by thermosensitive nanosphere polymer (TNP), synthesized from the copolymerization of N-isopropylacrylamide and 3-allyloxy-1,2-propanediol, was investigated. The effect of pH, contact time, and the initial concentration on the removal amount was studied. The highest removal amount of these poisons by TNP occurred at pH 7. The contact time increase improves the removal amount and the equilibrium contact time for diazinon and chlorpyrifos was 10 and 18 min, respectively. For low concentration of less than 50 mgL−1it was shown that removal capacity remains above 95%. The initial concentration above 50 mgL−1decreased the removal amount, in which chlorpyrifos showed a greater decrease. The kinetic data has been checked using pseudo first-order, pseudo second-order, and intraparticle diffusion equations. The intraparticle diffusion model had the best conformability for the adsorption process.


2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Yuan Lu ◽  
Dankui Liao ◽  
Xuezhen Feng ◽  
Hualin Meng ◽  
Yuting Lu ◽  
...  

A metal affinity-immobilized magnetic liposome (MA-IML) was prepared in this research, which was with lipid and Ni2+ content of 143.25 μg/mg and 32 μmol/mg, respectively. The antihypertensive peptides Ile-Pro-Pro (IPP) and Val-Pro-Pro (VPP) could be adsorbed onto MA-IML under specific conditions, and the adsorption kinetics was explored. The pseudo-second-order kinetics (R2 value>0.98) was more suitable to describe the adsorption process of IPP and VPP than the intraparticle diffusion model and pseudo-first-order kinetic model. The results indicated that MA-IML could be used as an adsorbent for screening antihypertensive peptides from natural products.


Author(s):  
Farid Abu Shammala ◽  
Barry Chiswell

This article describes a novel and efficient MCTS/GO nanocomposite for the accumulation and removal of a hazardous azo dye (Chrysoidine Y) from its aqueous solutions. Magnetic Chitosan /graphene oxide (MCTS/GO) nanocomposite adsorbent was prepared by wet-spinning technique, was used as accumulation and removal of Chrysoidine Y from aqueous solution. The structure and morphology of MCTS/GO nanocomposites were investigated using transmission electron microscope (TEM) and Fourier transform infrared (FTIR) spectroscopy were carried out on the MCTS/GO before the Chrysoidine Y (CY) accumulation experiments. The adsorption kinetics and isotherm studies were conducted under different conditions (pH = 3-7 and CY concentration = 100-400 mg/L) to examine the accumultion efficiency of the MCTS/GO towards CY in aqueous solution. The kinetics data of the adsorption process were analyzed using different kinetic models in order to investigate the adsorption behavior of CY on MCTS/GO. The results showed that the maximum adsorption capacity of the MCTS/GO nanocomposites towards CY can achieve up to ~700 mg/g for the adsorption at 300 mg/L CY. Kinetic data of adsorption process were found to fit pseudo-second order model as compared with pseudo-first-order model. The intraparticle diffusion model suggested that the adsorption process of MCTS/GO towards CY was dominated by the external mass transfer of CY molecules to the surface of MCTS/GO.


2019 ◽  
Vol 4 (12) ◽  
pp. 78-85
Author(s):  
Aboiyaa A. Ekine ◽  
Patience N. Ikenyiri ◽  
O. Hezekiah-Braye

This Research investigated the adsorption capacity of locally prepared adsorbents from Egg shells for the removal of fluoride ion in well water. It evaluated the performance of these adsorbents calcinated at 3000C and modified with 1.0M HNO3 (trioxonitrate (v)) acid. Batch adsorber was used to allow for interaction between adsorbent (grounded Egg shells) with water containing fluoride ion. The batch experiment was performed with particle size of 2.12 contact time (60, 120, 180, 240, 300min), mass dosage (5g, 10g, 15g, 20g) and temperature (250C, 300C, 400C, 500C). The modified adsorbent was characterized to determine the physiochemical properties of grounded Egg shells (GE). Also the chemical composition of the modified adsorbent was analyzed to determine the percentage of calcium element required for the uptake of the fluoride ions in water for calcium as 39.68% for grounded Egg shells (GE). Percentage adsorption increased with increase in contact time, mass dosage and temperature for the adsorbent. The adsorption capacity was also determined which also increased with increase in contact time, temperature but decreased with increase in mass dosage at constant time of 60minutes. The pseudo first-order, pseudo second order and intraparticle diffusion kinetic models were fitted into the experimental results. The results obtained indicated that the pseudo first order and intraparticle diffusion models for the grounded Egg shells (GE) reasonably described the adsorption process very well whereas the pseudo second order model was not suitable for a calcinations temperature of 3000C and particle size of 2.12m. The adsorption isotherms were obtained from equilibrium experiment Performed at temperature of 25, 35, 45 and 550C. The result showed that Langmuir and Freundlich isotherm fitted perfectly the experimental data. However, the negative values of Gibb’s free energy indicated that adsorption was favourable and the positive enthalpy change H0 revealed that adsorption process was endothermic while the positive value of the entropy change signified increased randomness with adsorption.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Sultan Alam ◽  
Luqman Khan ◽  
Luqman Ali Shah ◽  
Noor Rehman ◽  
◽  
...  

AbstractHomo and copolymer hydrogels of acrylamide and 2-hydroxyethyl methacrylate (HEMA) were synthesized by free radical addition polymerization. The synthesized hydrogels were characterized by scanning electron microscopy (SEM), thermal gravimetric and differential thermal analysis (TGA/DTA). The hydrogels were used as an adsorbent for the removal of toxic azo dye Basic blue 3 (BB3) in aqueous medium. To check the swelling property the equilibrium swelling of these synthesized hydrogels were established within 24 h. The effect of pH, time and temperature in the process of BB3 adsorption was studied in detail. The maximum adsorption of BB3 on hydrogels was occurred at pH 9 with 60 min equilibration time. The kinetic data were applied to pseudo first order, pseudo second order and intraparticle diffusion model. The obtained results indicate that the adsorption process, obey pseudo second order kinetics and is diffusion control. The negative value of ΔS and positive values of ΔG and ΔH showed that the adsorption process is orderliness, non-spontaneous and endothermic respectively in nature. The hydrogels were successfully regenerated from the mixture and used again in several steps without a reduction in their efficiency.


2021 ◽  
Vol 55 (9-10) ◽  
pp. 1131-1142
Author(s):  
BENGÜ ERTAN ◽  

Stinging nettle was used as lignocellulosic adsorbent for the removal of cationic dye – malachite green (MG), and anionic dye – Congo red (CR), from aqueous solution, without any chemical pretreatment. The adsorption equilibrium data fitted well with the Langmuir model for the adsorption of both dyes, with the calculated maximum adsorption capacity of 270.27 mgg-1 and 172.14 mgg-1 for MG and CR, respectively. The adsorption process was controlled by the pseudo-second-order model in the adsorption of MG and by the pseudo-first-order model in the adsorption of CR. The thermodynamics modelling displayed that the process was spontaneous and endothermic. The π–π electron–donor interaction, hydrogen bonds and pore diffusion may also be effective, besides electrostatic interaction between the adsorbate and the adsorbent in the mechanism of MG and CR uptake.


2019 ◽  
Vol 298 ◽  
pp. 128-132 ◽  
Author(s):  
To Uyen T. Dao ◽  
Hong Tham T. Nguyen ◽  
Do Trung Sy ◽  
Khoa Hien Nguyen ◽  
Anh Tien Nguyen ◽  
...  

The equilibrium and physicochemical properties of the Ca-Al LDH material were determined in this study. Kinetic data were analyzed using isothermal models including Langmuir, Freundlich, Temkin and Dubinin–Radushkevich. Adsorption behavior is well described by the Langmuir isotherm and the pseudo-second-order model. The maximum adsorption capacity of CR on Ca-Al LDH is found to be 72.569 mg/g. The uptake results indicated that the adsorption process was controlled by chemical processes and single-layer adsorption. Due to, the Ca-Al LDH material may be become an effective adsorbent for removal CR dye in aqueous solution.


2011 ◽  
Vol 233-235 ◽  
pp. 1972-1980 ◽  
Author(s):  
Yu Bin Tang ◽  
Fang Yu ◽  
Fang Yan Chen ◽  
Cheng Chen

Rectorite (REC), humic acid (HA) and polyvinyl alcohol (PVA) were used to prepare microspheres. Batch adsorption experiments of Pb2+ion on to the microspheres were performed. The results obtained indicate that adsorption time, the microspheres dosage and temperature were the main factors influencing the adsorptive capacities. The adsorption data for Pb2+ion were well described by the Freundlich, Langmuir and Temkin models. The kinetic experimental data properly correlated with the pseudo-first-order model, pseudo-second-order model and Elovich equation. The adsorption process is spontaneous, endothermic and out-of-order. The whole adsorption process is mainly controlled by entropies. The adsorption can be classified as chemical adsorption. The mechanisms for the adsorption of Pb2+ion on to the microspheres involved ion-exchange adsorption of Pb2+or the formation of complex compound. Under the experimental conditions employed, the removal of Pb2+ion attained value of 96.05%.


2012 ◽  
Vol 610-613 ◽  
pp. 514-517 ◽  
Author(s):  
Xue Chuan Wang ◽  
Fei Fei Zhang ◽  
Tao Tao Qiang

Collagen fiber loaded hyperbranched polyamide-amine(CF-HBPN) was prepared by the crosslinking power of glutaraldehyde. The structure of CF-HBPN before and after adsorption was characterized and analyzed via scanning electron microscopy. The CF-HBPN was effective adsorbent for the removal of Cr(VI) from aqueous solutions. The adsorption isotherm and kinetic of the adsorption process were studied. The experimental results were fitted using the Langmuir, Freundlich and Temkin equations. The experimental results indicated that the Langmuir isotherm was better in describing the adsorption process. Two kinetic models, the pseudo-first order and pseudo-second order, were used to analyze the kinetic data. The pseudo-second order model was proven to be better in describing the adsorption behavior.


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