scholarly journals Adsorption and equilibrium studies of phenol and para-nitrophenol by magnetic activated carbon synthesised from cauliflower waste

2019 ◽  
Vol 25 (5) ◽  
pp. 742-752 ◽  
Author(s):  
Nidhi Yadav ◽  
Dhruv Narayan Maddheshiaya ◽  
Shalu Rawat ◽  
Jiwan Singh

In this study, waste cauliflower leaves were used for adsorbent preparation. The waste cauliflower leaves were converted into activated carbon by pyrolysis at two different temperatures 250˚C and 500˚C with magnetic property. The prepared adsorbents were denoted as CAC-250 and CAC-500 and characterized by the use of scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The adsorbents were applied for the removal of phenol and PNP from their aqueous solutions. The adsorption of phenol was found very less by the application CAC-250, whereas by the application of CAC-500 the adsorption of both phenol and PNP was enhanced. The maximum adsorption of phenol was found 99% and that of PNP was found ~100% using CAC-500, with initial adsorbate concentration 5 mg/L at 25˚C. The adsorption data was analysed with Langmuir, Freundlich and Temkin isotherm models and different kinetic models that are pseudo first order, pseudo second order, Elovich, intraparticle and pore diffusion model.

2012 ◽  
Vol 14 (4) ◽  
pp. 88-94 ◽  
Author(s):  
R.P. Suresh Jeyakumar ◽  
V. Chandrasekaran

Abstract In this work, the efficiency of Ulva fasciata sp. activated carbons (CCUC, SCUC and SSUC) and commercially activated carbon (CAC) were studied for the removal of Cu (II) ions from synthetic wastewater. Batch adsorption experiments were carried out as a function of pH, contact time, initial copper concentration and adsorbent dose. The percentage adsorption of copper by CCUC, SSUC, SCUC and CAC are 88.47%, 97.53%, 95.78% and 77.42% respectively. Adsorption data were fitted with the Langmuir, Freundlich and Temkin models. Two kinetic models pseudo first order and the pseudo second order were selected to interpret the adsorption data.


2015 ◽  
Vol 4 (6) ◽  
pp. 289-296 ◽  
Author(s):  
Hind Yaacoubi ◽  
Zuo Songlin ◽  
Mustapha Mouflih ◽  
Mina Gourai ◽  
Said Sebti

Sedimentary phosphate (SP) was used as an adsorbent for the removal of 2-nitrophenol from aqueous solutions in an attempt to investigate (the feasibility of) its application (to) in wastewater purification.  The adsorbent was characterized by X-ray diffraction (XRD), IR spectroscopy, Fluorescence X and BET.  The results indicated that the SP (was) is francolite (Ca10 (PO4,CO3)6F2) and mesoporous. The effect of the adsorption time and the pH of the solution were studied. The pseudo-first-order, pseudo-second-order and intraparticle diffusion models were used to fit adsorption data in the kinetic studies. The equilibrium isotherms were determined using the Langmuir, Freundlich and Dubinin-Radushkevich models. The results show that the Dubinin-Radushkevich isotherm had better agreement with the 2-nitrophenol adsorption on SP with a correlation coefficient of 0.98, an equilibrium adsorption capacity of 633 mg. g-1 and a corresponding contact time of 2 h. The results imply that intraparticle diffusion could be summarized as the basic rate-controlling mechanisms during 2-nitrophenol adsorption on SP.


2011 ◽  
Vol 356-360 ◽  
pp. 1524-1527
Author(s):  
Mei Li ◽  
Yi Luo ◽  
Ru Chun Wu ◽  
Hong Yu Liang ◽  
Shuang Fei Wang

The adsorption of phenol onto activated carbon fiber (ACF) from aqueous solutions were studied.The adsorption kinetics of phenol by ACF can be described by the Lagergren first-order and pseudo second-order kinetic models, respectively.The Lagergren first-order was verified to be the best to describe the adsorption data. The intraparticle diffusion is not the only rate-controlling step .


2019 ◽  
Vol 9 (8) ◽  
Author(s):  
Wassila Boulaiche ◽  
Badreddine Belhamdi ◽  
Boualem Hamdi ◽  
Mohamed Trari

Abstract This work reports the application of Posidonia oceanica for the elimination of heavy metals M(II) (M = Zn, Cd, Ni, Cu and Pb) by biosorption in batch system. The effect of the contact time, initial M concentration, pH and temperature was considered. The kinetic and equilibrium models for the M-biosorption were tested namely the pseudo-first-order, pseudo-second-order and Elovich kinetic models. Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherms models have also been used to fit equilibrium adsorption data. The adsorption kinetics follow a pseudo-second-order model for all studied systems, and the equilibrium data are suitably fitted by the above models. The amount of adsorbed metals by biosorption is 48.33, 43.9, 41.02, 37.90 and 30.22 mg/g for Pb(II), Cu(II), Ni(II), Zn(II) and Cd(II), respectively. The thermodynamic parameters suggested that the metal biosorption is spontaneous with an endothermic nature.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohamed S. Yahia ◽  
Ahmed S. Elzaref ◽  
Magdy B. Awad ◽  
Ahmed M. Tony ◽  
Ahmed S. Elfeky

Abstract Commercial Granulated Active Carbon (GAC) has been modified using 10 Gy dose Gamma irradiation (GAC10 Gy) for increasing its ability of air purification. Both, the raw and treated samples were applied for removing Chlorpyrifos pesticide (CPF) from ambient midair. Physicochemical properties of the two materials were characterized by Fourier Transform Infrared (FT-IR) and Raman spectroscopy. The phase formation and microstructure were monitored using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), supported with Energy-Dispersive X-ray (EDX). The Surface area measurement was detected using BET particle size prosometry. Obtained outcomes showed that, the maximum adsorption capacity, given by Langmuir equations, was greatly increased from 172.712 to 272.480 mg/g for GAC and GAC10 Gy, respectively, with high selectivity. The overall removal efficiency of GAC10 Gy was notably comparable to that of the original GAC-sorbent. The present study indicated that, gamma irradiation could be a promising technique for treating GAC and turned it more active in eliminating the pesticides pollutants from surrounding air. The data of equilibrium has been analyzed by Langmuir and Freundlich models, that were considerably better suited for the investigated materials than other models. The process kinetics of CPF adsorbed onto both tested carbon versions were found to obey the pseudo first order at all concentrations with an exception at 70 mg/l using GAC, where, the spontaneous exothermic adsorption of Chlorpyrifos is a strong function for the pseudo-first order (PFO) and pseudo second order (PSO) kinetics.


2011 ◽  
Vol 46 (1) ◽  
pp. 101-104 ◽  
Author(s):  
S Naeem ◽  
U Zafar ◽  
T Amann

In this investigation, adsorption of cyanide has been studied by means of batch-technique. Percentage adsorption was determined for Rice Husk Ash (RHA)-Cyanide solution system as a function of i) contact time, ii) pH, iii) adsorbate concentration and iv) temperature. Adsorption data has been interpreted in terms of Freundlich and Langmuir equations. Thermodynamics parameters for the adsorption system have been determined at three different temperatures. The value of ΔH°=38.326KJ/mole and ΔG°=-6.117KJ/mole at 283°K suggest that the adsorption of cyanide on RHA is an endothermic and a spontaneous process.Key words: Cyanide; Rice husk ash (RHA); Adsorption Isotherms DOI: http://dx.doi.org/10.3329/bjsir.v46i1.3524 Bangladesh J. Sci. Ind. Res. 46(1), 101-104, 2011


2008 ◽  
Vol 6 (4) ◽  
pp. 581-591 ◽  
Author(s):  
Lyudmila Belyakova ◽  
Oleksandra Shvets ◽  
Diana Lyashenko

AbstractThe present work investigates the adsorptive interactions of Hg(II) ions in aqueous medium with hydroxylated silica, aminopropylsilica and silica chemically modified by β-cyclodextrin. Batch adsorption studies were carried out with various agitation times and mercury(II) concentrations. The maximum adsorption was observed within 15–30 min of agitation. The kinetics of the interactions, tested with the model of Lagergren for pseudo-first and pseudo-second order equations, showed better agreement with first order kinetics (k1 = 3.4 ± 0.2 to 5.9 ± 0.3 min−1). The adsorption data gave good fits with Langmuir isotherms. The results have shown that β-cyclodextrin-containing adsorbent has the largest adsorption specificity to Hg(II): K L = 4125 ± 205 mmol−1. “β-cyclodextrin-NO3-” inclusion complexes with ratio 1: 1 and super molecules with composition C42H70O35 ⊎ 3 Hg(NO3)2 are formed on the surface of β-cyclodextrin-containing silica.


2011 ◽  
Vol 704-705 ◽  
pp. 486-491
Author(s):  
Yi Nan Hao ◽  
Xi Ming Wang ◽  
Li Jun Ding ◽  
Da Yan Ma

Xanthoceras Sorbifolia Bunge hull activated carbon (XSBHAC) developed by phosphoric acid activation for removing basic fuchsin (BF) has been investigated. Experiments were carried out as function of contact time, pH (4-10) and temperature (303,313 and 323K). Adsorption isotherms were modeled with the Langmuir and Freundlich isotherms. The data fitted well with the Langmuir isotherm. The Langmuir monolayer saturation capacities of BF adsorbed onto activated carbon were 351.35, 354.96 and 355.94 mg/g at 303,313, and 323 K, respectively.The kinetic models were also studied .The rates of adsorption were found to conform to the pseudo-second-order kinetics with good correlation.Using the equilibrium concentration contents obtained at different temperatures, various thermodynamic parameters,such as △G,△H and △S, have been calculated. The thermodynamics parameters of system indicated spontaneous and endothermic process. Key words: Xanthoceras sorbifolia bunge hull;biosorption; basic fuchsin


2020 ◽  
Vol 49 (1) ◽  
pp. 55-62
Author(s):  
Akbar Eslami ◽  
Zahra Goodarzvand Chegini ◽  
Maryam Khashij ◽  
Mohammad Mehralian ◽  
Marjan Hashemi

Purpose A nanosilica adsorbent was prepared and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and BET. Design/methodology/approach The optimum conditions for the highest adsorption performance were determined by kinetic modeling. The adsorbent was used for the adsorption of acetaminophen (ACT), and the parameters affecting the adsorption were discussed like pH, initial concentration, contact time and adsorbent dosage. The adsorbent have been characterized by SEM, XRD and BET analysis. The kinetic models including pseudo-first-order and pseudo-second-order with Langmuir and Freundlich isotherm models were applied to investigate the kinetic and isotherms parameters. Findings The adsorption of ACT increased to around 95% with the increase of nanosilica concentration to 30 g/L. Moreover, the adsorption process of ACT follows the pseudo-second-order kinetics and the Langmuir isotherm with the maximum adsorption capacity of 609 mg/g. Practical implications This study provided a simple and effective way to prepare of nanoadsorbents. This way was conductive to protect environmental and subsequent application for removal of emerging pollutants from aqueous solutions. Originality/value The novelty of the study is synthesizing the morphological and structural properties of nanosilica-based adsorbent (specific surface area, pore volume and size, shape and capability) and improving its removal rate through optimizing the synthesis method; and studying the capability of synthesis of nanosilica-based adsorbent for removal of ACT as a main emerging pharmaceutical water contaminant.


2019 ◽  
Vol 55 (2) ◽  
pp. 132-144 ◽  
Author(s):  
Amir Hossein Mahvi ◽  
Arash Dalvand

Abstract In this research, the adsorption of the Direct Red 23 dye from synthetic textile wastewater using nanoclay was studied in a batch system. The properties of nanoclay were investigated by scanning electron microscope, Fourier transform infrared, and EDX analysis. The specific surface area of the nanoclay was determined using Sear's method. The results revealed that with increasing adsorbent dose and contact time and decreasing pH, ionic strength, and adsorbate concentration, dye removal efficiency has increased. Nanoclay could remove 99.4% dye from the solution containing 50 mg/L dye at 30 min. The results indicated that dye removal followed pseudo-second-order kinetic (R2 > 0.99) and the Langmuir isotherm. According to the findings, nanoclay is an effective adsorbent for direct dye removal from wastewater.


Sign in / Sign up

Export Citation Format

Share Document