scholarly journals Photocatalytic Degradation of Eosin Yellow Using Poly(pyrrole-co-aniline)-Coated TiO2/Nanocellulose Composite under Solar Light Irradiation

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
T. S. Anirudhan ◽  
S. R. Rejeena

The present study describes the feasibility of a novel adsorbent cum photocatalyst, poly(pyrrole-co-aniline)-coated TiO2/nanocellulose composite (P(Py-co-An)-TiO2/NCC), to remove eosin yellow (EY) from aqueous solutions. The removal of EY was investigated by batch adsorption followed by photocatalysis. The effect of various adsorption parameters like adsorbent dose, pH, contact time, initial concentration, and ionic strength has been optimized for treating effluents from the dye industry. Adsorption of EY reached maximum at pH 4.5 and complete removal of dye was achieved using 3.5 g/L of P(Py-co-An)-TiO2/NCC. Adsorption equilibrium data were fitted with Langmuir and Fritz-Schlunder isotherm models and the kinetics of adsorption follows a second-order mechanism. The adsorption capacity of P(Py-co-An)-TiO2/NCC was found to be 3.39 × 10−5 mol/g and reached equilibrium within 90 min. The photocatalytic degradation of adsorbed dye under sunlight was possible and about 92.3% of dye was degraded within 90 min. The reusability of P(Py-co-An)-TiO2/NCC was also investigated. The results indicate that P(Py-co-An)-TiO2/NCC is the best material for the wiping out of EY from aqueous solutions.

2019 ◽  
Vol 9 (8) ◽  
Author(s):  
Pezhman Zein Al-Salehin ◽  
Farid Moeinpour ◽  
Fatemeh S. Mohseni-Shahri

Abstract In the present paper, used cigarette filter ash was prepared and used as an active adsorbent to remove As(III) ions from aqueous solutions. The prepared adsorbent structure was identified by scanning electron microscopy analysis, Brunauer–Emmett–Teller method and energy-dispersive X-ray spectroscopy analysis. The influence of contact time, pH, adsorbent dose and initial concentration of As(III) on the removal of As(III) was assessed. Several isotherm models were checked to illustrate the adsorption equilibrium. The adsorption equilibrium data adapted well with the Langmuir isotherm model. The maximum adsorption capacity of 33.33 mg/g was acquired from the Langmuir isotherm. The calculated thermodynamic variables verified that the adsorption process is spontaneous and endothermic.


2011 ◽  
Vol 354-355 ◽  
pp. 33-36
Author(s):  
Jian Yun Li ◽  
Quan Xian Hua ◽  
Jun Ling Niu ◽  
Jian Wei Tang ◽  
Ke Xu

The adsorption of copper in aqueous solutions by steel slag was studied in batch adsorption experiments. The adsorption equilibrium data fitted best with Langmuir and Freundlich equations. The adsorption was preferential type. A comparison of the kinetics models on the apparent adsorption rate showed that the adsorption system was best described by the pseudo-second-order kinetics. The adsorption rate was controlled by both liquid film diffusion and intraparticle dispersion.


2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Ingrid Johanna Puentes-Cárdenas ◽  
Griselda Ma. Chávez-Camarillo ◽  
César Mateo Flores-Ortiz ◽  
María del Carmen Cristiani-Urbina ◽  
Alma Rosa Netzahuatl-Muñoz ◽  
...  

The adsorption performance of a Cu-TiO2composite for removing acid blue 80 (AB80) dye from aqueous solutions was investigated in terms of kinetics, equilibrium, and thermodynamics. The effect of operating variables, such as solution pH, initial dye concentration, contact time, and temperature, on AB80 adsorption was studied in batch experiments. AB80 adsorption increased with increasing contact time, initial dye concentration, and temperature and with decreasing solution pH. Modeling of adsorption kinetics showed good agreement of experimental data with the pseudo-second-order kinetics model. The experimental equilibrium data for AB80 adsorption were evaluated for compliance with different two-parameter, three-parameter, and four-parameter isotherm models. The Langmuir isotherm model best described the AB80 adsorption equilibrium data. The thermodynamic data revealed that the AB80 adsorption process was endothermic and nonspontaneous. Kinetics, equilibrium, and thermodynamic results indicate that Cu-TiO2adsorbs AB80 by a chemical sorption reaction.


2001 ◽  
Vol 19 (3) ◽  
pp. 197-210 ◽  
Author(s):  
A. Hashem ◽  
Reda M. El-Shishtawy

The factors influencing the cationization of microcrystalline cellulose with 3-chloro-2-hydroxypropyl triethylammonium chloride in the presence of NaOH were investigated. The course of the reaction was followed by estimating the nitrogen content of the cationized product while its structural features were confirmed by IR analysis. The ability of cationized cellulose to adsorb anionic dyes, viz. Acid Orange 7, Direct Blue 75 and Direct Violet 31, was investigated at 25°C and 50°C. The equilibrium data obtained were fitted by the Langmuir and Freundlich isotherm models, allowing the corresponding adsorption parameters to be determined. The results showed that the adsorption capacity was dependent on the adsorbent, temperature, the nature of the dye and (to some extent) on van der Waals and hydrogen bonding. Cationized cellulose exhibited a much better adsorption capacity towards anionic dyes than cellulose.


2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Bayram Kizilkaya ◽  
A. Adem Tekınay

Removal of lead (II) from aqueous solutions was studied by using pretreated fish bones as natural, cost-effective, waste sorbents. The effect of pH, contact time, temperature, and metal concentration on the adsorption capacities of the adsorbent was investigated. The maximum adsorption capacity for Pb (II) was found to be 323 mg/g at optimum conditions. The experiments showed that when pH increased, an increase in the adsorbed amount of metal of the fish bones was observed. The kinetic results of adsorption obeyed a pseudo second-order model. Freundlich and Langmuir isotherm models were applied to experimental equilibrium data of Pb (II) adsorption and the value ofRLfor Pb (II) was found to be 0.906. The thermodynamic parameters related to the adsorption process such asEa,ΔG°,ΔH°, andΔS° were calculated andEa,ΔH°, andΔS° were found to be 7.06, 46.01 kJ mol−1, and 0.141 kJ mol−1K−1for Pb (III), respectively.ΔH° values (46.01 kJmol−1) showed that the adsorption mechanism was endothermic. Weber-Morris and Urano-Tachikawa diffusion models were also applied to the experimental equilibrium data. The fish bones were effectively used as sorbent for the removal of Pb (II) ions from aqueous solutions.


2021 ◽  
Vol 875 ◽  
pp. 177-183
Author(s):  
Asma Ameer ◽  
Syed Mujtaba Ul Hassan ◽  
Syed M. Husnain ◽  
Jamil Ahmad ◽  
Faisal Shahzad ◽  
...  

This work explores the potential of adsorption of Pb2+ by hydrothermally synthesized alumina. In comparison to other heavy ion removal techniques, adsorption is preferred in the current study as it has the edge of ease of operation and environment friendly characteristics. Synthesis of high surface area alumina whiskers was achieved by hydrothermal route which were subsequently employed for the active adsorption of lead ions. AACH (Ammonium Aluminum Carbonate Hydroxide), used as precursor for alumina, was calcined at three different temperatures i.e. 700, 900 and 1100 °C to form alumina whiskers. These whiskers were characterized by XRD, SEM, BET and FTIR. Various adsorption parameters such as contact time, pH, initial metal concentration were studied for lead ions. Maximal removal efficiency was obtained for the specimen having pH 4 and calcined at 700 °C for 60 minutes. Kinetic data was best described by pseudo second order model, whereas the adsorption equilibrium data obeyed the Langmuir adsorption isotherm model.


2020 ◽  
Vol 10 (5) ◽  
pp. 1738
Author(s):  
Kay Thwe Aung ◽  
Seung-Hee Hong ◽  
Seong-Jik Park ◽  
Chang-Gu Lee

Polyacrylonitrile (PAN) fibers were prepared via electrospinning and were modified with diethylenetriamine (DETA) to fabricate surface-modified PAN fibers. The surface-modified PAN fibers were used to evaluate their adsorption capacity for the removal of Cu(II) from aqueous solutions. Batch adsorption experiments were performed to examine the effects of the modification process, initial concentration, initial pH, and adsorbent dose on the adsorption of Cu(II). Kinetic analysis revealed that the experimental data fitted the pseudo-second-order kinetic model better than the pseudo-first-order model. Adsorption equilibrium studies were conducted using the Freundlich and Langmuir isotherm models, and the findings indicated that the PAN fibers modified with 85% DETA presented the highest adsorption capacity for Cu(II) of all analyzed samples. Moreover, the results revealed that the Freundlich model was more appropriate than the Langmuir one for describing the adsorption of Cu(II) onto the modified fibers at various initial Cu(II) concentrations. The maximum adsorption capacity was determined to be 87.77 mg/g at pH 4, and the percent removal of Cu(II) increased as the amount of adsorbent increased. Furthermore, the surface-modified PAN fibers could be easily regenerated using NaOH solution. Therefore, surface-modified PAN fibers could be used as adsorbents for the removal of Cu(II) from aqueous solutions.


2012 ◽  
Vol 9 (3) ◽  
pp. 1389-1399 ◽  
Author(s):  
R. Hema Krishna ◽  
A. V. V. S. Swamy

The powder of mosambi fruit peelings (PMFP) was used as an adsorbent for the removal of heavy metal like Cr (VI) from aqueous solutions was studied using batch tests. The influence of physico-chemical key parameters such as the initial metal ion concentration, pH, agitation time, adsorbent dosage, and the particle size of adsorbent has been considered in batch tests. Sorbent ability to adsorb Cr (VI) ions was examined and the mechanism involved in the process investigated. The optimum results were determined at an initial metal ion concentration was 10 mg/lit, pH=2, agitation time – 60 min, an adsorbent dose (150 mg/50 ml) and the particle size (0.6 mm). The % adsorption, Langmuir constants [Q0=7.51(mg/g) and b=1.69(mg/lit)] Freundlich constant(Kf=2.94), Lagergren rate constants (Kad(min-1)=5.75 x 10-2) for [Cr(VI)] 10 mg/lit were determined for the adsorption system as a function of sorbate concentration. The equilibrium data obtained were tested using Langmuir, Freundlich adsorption isotherm models, and the kinetic data obtained were fitted to pseudo first order model.


2015 ◽  
Vol 71 (11) ◽  
pp. 1611-1619 ◽  
Author(s):  
Jun Liu ◽  
Hongyan Du ◽  
Shaowei Yuan ◽  
Wanxia He ◽  
Pengju Yan ◽  
...  

Alkaline deoxygenated graphene oxide (aGO) was prepared through alkaline hydrothermal treatment and used as adsorbent to remove Cd(II) ions from aqueous solutions for the first time. The characterization results of transmission electron microscopy, X-ray diffraction, Raman spectroscopy, and Fourier transform infrared (FT-IR) spectra indicate that aGO was successfully synthesized. The batch adsorption experiments showed that the adsorption kinetics could be described by the pseudo-second-order kinetic model, and the isotherms equilibrium data were well fitted with the Langmuir model. The maximum adsorption capacity of Cd(II) on aGO was 156 mg/g at pH 5 and T = 293 K. The adsorption thermodynamic parameters indicated that the adsorption process was a spontaneous and endothermic reaction. The mainly adsorption mechanism speculated from FT-IR results may be attributed to the electrostatic attraction between Cd2+ and negatively charged groups (–CO−) of aGO and cation-π interaction between Cd2+ and the graphene planes. The findings of this study demonstrate the potential utility of the nanomaterial aGO as an effective adsorbent for Cd(II) removal from aqueous solutions.


2014 ◽  
Vol 894 ◽  
pp. 121-124 ◽  
Author(s):  
Yan Qiang Jian ◽  
Ming Yu Li ◽  
Qing Xuan Zeng

A chelating ion exchange fiber containing thioureido groups for the removal of Cr (VI) has been prepared from chloramethylated styrene grafted polypropylene fiber (2.96 mmol/g Cl) reacted with thiourea, batch adsorption experiments are adopted to investigate its adsorption equilibrium properties, Adsorption isotherms at various temperatures were obtained. Langmuir linear equation model can well describe the adsorption equilibrium data suggesting that the adsorption process involves both chemisorption and physisorption. The values of thermodynamic parameters, including ΔH, ΔGand ΔS, indicate that the adsorption of Cr (VI) is a spontaneous, entropy-driven and endothermic process.


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