Process optimization and enhancement of pesticide adsorption by porous adsorbents by regression analysis and parametric modelling

AbstractIn the present study, the adsorptive removal of organophosphate diazinon pesticide using porous pumice adsorbent was experimentally investigated in a batch system, modelled and optimized upon response surface methodology (RSM) and artificial neural network-genetic algorithm (ANN-GA), fitted to isotherm, kinetic and thermodynamic models. The quantification of adsorbent elements was determined using EDX. XRD analysis was utilized to study the crystalline properties of adsorbent. The FT-IR spectra were taken from adsorbent before and after adsorption to study the presence and changes in functional groups. The constituted composition of the adsorbent was determined by XRF. Also, the ionic strength and adsorbent reusability were explored. The influences of operational parameters like pH, initial pesticide concentration, adsorbent dosage and contact time were investigated systematically. ANN-GA and RSM techniques were used to identify the optimal process variables that result in the highest removal. Based on the RSM approach, the optimization conditions for maximum removal efficiency is obtained at pH = 3, adsorbent dosage = 4 g/L, contact time = 30 min, and initial pesticide concentration = 6.2 mg/L. To accurately identify the parameters of nonlinear isotherm and kinetic models, a hybrid evolutionary differential evolution optimization (DEO) is applied. Results indicated that the equilibrium adsorption data were best fitted with Langmuir and Temkin isotherms and kinetic data were well described by pseudo-first and second-order kinetic models. The thermodynamic parameters such as entropy, enthalpy and Gibbs energy were evaluated to study the effect of temperature on pesticide adsorption.

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Adsorption of Cr(VI) by Natural Clinoptilolite Zeolite from Aqueous Solutions: Isotherms and Kinetics

Polish Journal of Chemical Technology ◽

10.1515/pjct-2017-0056 ◽

2017 ◽

Vol 19 (3) ◽

pp. 106-114 ◽

Cited By ~ 13

Author(s):

Sahand Jorfi ◽

Mohammad Javad Ahmadi ◽

Sudabeh Pourfadakari ◽

Nematollah Jaafarzadeh ◽

Reza Darvishi Cheshmeh Soltani ◽

...

Keyword(s):

Experimental Data ◽

Aqueous Solutions ◽

Contact Time ◽

Chromium Concentration ◽

Order Kinetic ◽

Operational Parameters ◽

Simple Modification ◽

Adsorbent Dosage ◽

Clinoptilolite Zeolite ◽

Natural Clinoptilolite

Abstract The main aim of this study was to evaluate the efficiency of natural zeolite for Cr(VI) removal from aqueous solutions. Following simple modification of adsorbent, the effect of operational parameters including pH (2–10), adsorbent dosage (2–20 g/L), contact time (5–150 min) and Cr(VI) concentration (10–50 mg/L) were studied according to one-factor-at-a-time procedure. The maximum Cr(VI) removal of 99.53% was obtained at initial pH of 2, contact time of 30 min, adsorbent dosage of 8 g/L and initial chromium concentration of 10 mg/L. The Freundlich isotherm was best fitted with experimental data (R2 = 0.951). Also, type 1pseudo second order kinetic model showed the most correlation (R2 = 1) with the experimental data. According to obtained results, it can be concluded that the application of clay-like adsorbents such as natural clinoptilolite zeolite can be considered as an efficient alternative for final treatment of effluents containing Cr(VI).

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Equilibrium and Kinetic Studies of Liquid Phase Adsorption of Methylene Blue Onto Phosphoric Acid Modified Bambaranut Shell

Acta Chemica Malaysia ◽

10.2478/acmy-2021-0007 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Eze Nkechinyere Olivia ◽

Ejimofor Samuel Adimchinobi ◽

Onuegbu Theresa Uzoma

Keyword(s):

Waste Water ◽

Methylene Blue ◽

Contact Time ◽

Average Pore Size ◽

Batch Process ◽

Blue Dye ◽

Order Kinetic ◽

Operational Parameters ◽

Average Pore ◽

Adsorbent Dosage

AbstractIn view of the global need to curb the effect of contaminants in waste water on our environment, the adsorption potentials of modified carbon from bambaranut (Vigna subterranean) shell was investigated for its efficiency in the removal of methylene blue from waste water. The adsorbent morphology and surface chemistry were established by Brunauer-Emmett-Teller (BET) determination and Scanning Electron Microscopy (SEM), as well as other standard laboratory procedures. The prepared material was used for the uptake of MB from aqueous solution in a batch process, using UV spectrophotometer Model 752 at 620nm to analyze for the residual dye concentration. The effect of operational parameters such as contact time, adsorbent dosage, initial dye concentration and pH were analyzed to determine the factors controlling the rate of adsorption. Results from the study showed that the active carbon prepared was a porous material, with surface area of 193 m2/g, average pore size of about 10.98nm, and pore volume of 0.530cm3/g. With increase in initial dye concentration from 15mg/l to 75mg/l, a decrease in percent adsorption from 95.4% to 72.19% was observed. Increase in adsorbent dosage (from 0.1g to 0.5g), contact time (from 5 min to 40 min) and pH from 2 to 10 resulted in increase in percent adsorption from 84.03% to 98.83%, 54.24% to 84% and 48.17% to 84.03% respectively. About 98.83% removal of MB dye was achieved after 20 min, at pH of 6, temperature of 27±2oC, 0.5g weight of adsorbent and initial concentration of 60mg/l of 50ml MB dye solution. Langmuir isotherm best fits the equilibrium adsorption data with R2 = 0.996; the adsorption intensity obtained from Freundlich model (n>1) and the energy of adsorption obtained from the D-R model (< 8kJ/mol) suggested that physisorption dominates the adsorption of methylene blue onto the prepared activated carbon. Adsorption kinetic data was best described using Pseudo second order kinetic model (R2 = 0.996), giving equilibrium rate constant (k2) of 7690g mg-1 min-1. The characteristic results showed that bambaranut shell can be employed as an alternative to commercial adsorbents in the removal of methylene blue dye from aqueous solutions and waste water.

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Adsorption of Acid Red 18 (AR18) by Activated Carbon from Poplar Wood- A Kinetic and Equilibrium Study

E-Journal of Chemistry ◽

10.1155/2010/958073 ◽

2010 ◽

Vol 7 (1) ◽

pp. 65-72 ◽

Cited By ~ 22

Author(s):

Reza Shokoohi ◽

Vahid Vatanpoor ◽

Mansuor Zarrabi ◽

Akram Vatani

Keyword(s):

Activated Carbon ◽

Removal Efficiency ◽

Kinetic Models ◽

Contact Time ◽

Isotherm Models ◽

Order Kinetic ◽

Poplar Wood ◽

Adsorbent Dosage ◽

First Order ◽

Pseudo First Order

Adsorption process by activated carbon is widely used for removal of dyes. Because of economical limits, activated carbon derived from low cost materials seem to be economical. The aim of this work is preparation of activated carbon from poplar wood and investigation of its ability to removal of (AR18) dye. In this work, we prepared the activated carbon by chemical activation method in electric furnace. In addition we have investigated effect of various parameters such as pH, contact time, dye concentration and adsorbent dosage on dye removal. Langmuir and Freundlich isotherm models have been investigated. Pseudo-first order, pseudo-second order and modified pseudo-first order kinetic models have been used for experimental data. The results showed that removal efficiency was increased with increasing of adsorbent dosage, contact time and decreasing of pH, but with increasing of dye concentration, the removal efficiency was decreased. Adsorption isotherm models showed that Langmuir isotherm model was best fitted onto collected data (r2>0.978). In addition, kinetic models showed that sorption of AR18 onto activated carbon prepared from poplar wood follows the pseudo-first order model (r2>0.9758).

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Extraction of Heavy Metals from Aqueous Medium by Husk Biomass: Adsorption Isotherm, Kinetic and Thermodynamic study

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2018-1182 ◽

2019 ◽

Vol 233 (2) ◽

pp. 201-223 ◽

Cited By ~ 8

Author(s):

Khalida Naseem ◽

Rahila Huma ◽

Aiman Shahbaz ◽

Jawaria Jamal ◽

Muhammad Zia Ur Rehman ◽

...

Keyword(s):

Metal Ions ◽

Aqueous Medium ◽

Contact Time ◽

Metal Ion ◽

Adsorption Process ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Adsorbent Dosage ◽

Adsorption Sites ◽

Order Kinetic Model

Abstract This study describes the adsorption of Cu (II), Co (II) and Ni (II) ions from wastewater on Vigna radiata husk biomass. The ability of adsorbent to capture the metal ions has been found to be in the order of Ni (II)>Co (II) and Cu (II) depending upon the size and nature of metal ions to be adsorbed. It has been observed that percentage removal of Cu (II), Co (II) and Ni (II) ions increases with increase of adsorbent dosage, contact time and pH of the medium but up to a certain extent. Maximum adsorption capacity (qmax) for Cu (II), Co (II) and Ni (II) ions has been found to be 11.05, 15.04 and 19.88 mg/g, respectively, under optimum conditions of adsorbent dosage, contact time and pH of the medium. Langmuir model best fits the adsorption process with R2 value approaches to unity for all metal ions as compared to other models because adsorption sites are seemed to be equivalent and only monolayer adsorption may occur as a result of binding of metal ion with a functional moiety of adsorbent. Pseudo second order kinetic model best interprets the adsorption process of Cu (II), Co (II) and Ni (II) ions. Thermodynamic parameters such as negative value of Gibbs energy (∆G°) gives information about feasibility and spontaneity of the process. Adsorption process was found to be endothermic for Cu (II) ions while exothermic for Co (II) and Ni (II) ions as signified by the value of enthalpy change (∆H°). Husk biomass was recycled three times for removal of Ni (II) from aqueous medium to investigate its recoverability and reusability. Moreover V. radiata husk biomass has a potential to extract Cu (II) and Ni (II) from electroplating wastewater to overcome the industrial waste water pollution.

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Adsorption of Pb(II) from Aqueous Solutions on Dithizone-Immobilized Coal Fly Ash

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.840.57 ◽

2020 ◽

Vol 840 ◽

pp. 57-63

Author(s):

Dina Fitriana ◽

Mudasir Mudasir ◽

Dwi Siswanta

Keyword(s):

Fly Ash ◽

Adsorption Isotherm ◽

Contact Time ◽

Coal Fly Ash ◽

Order Kinetic ◽

Adsorbent Dosage ◽

Activated Coal ◽

Concentration Of Ions ◽

Order Kinetic Model ◽

Pseudo Second Order

Adsorption of Pb(II) ions onto selective adsorbent of dithizone-immobilized coal fly ash (DCFA) from Holcim, Cilacap, Indonesia has been investigated in batch experiments. Prepared coal fly ash (CFA) modified by immobilization of dithizone previously were characterized by FT-IR and XRD. Several parameters influencing the adsorption of Pb(II) ions such as effect of pH, adsorbent dosage, contact time and initial concentration of ions on the efficiency of the adsorption were studied. The optimum condition of Pb(II) adsorption was found at pH 5, adsorbent dosage 0.1 g, contact time 60 min and initial Pb(II) ions concentration of 60 mg L–1. The adsorption kinetics of Pb(II) ions on DCFA was found to follow a pseudo-second-order kinetic model. The adsorption isotherm data were fitted to the Langmuir model. Kinetics and adsorption isotherm studies suggest that the capacity and affinity of the DCFA in adsorbing Pb(II) ions is significantly improved compared to those of non-immobilized activated coal fly ash (ACFA).

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Adsorption of methylene blue from aqueous solutions by pyrolusite ore

Mongolian Journal of Chemistry ◽

10.5564/mjc.v18i44.880 ◽

2018 ◽

Vol 18 (44) ◽

pp. 5-11 ◽

Cited By ~ 3

Author(s):

Nizamettin Demirkıran ◽

G D Turhan Özdemir ◽

M Saraç ◽

M Dardağan

Keyword(s):

Methylene Blue ◽

Particle Size ◽

Contact Time ◽

Average Particle Size ◽

Dye Adsorption ◽

Blue Dye ◽

Average Particle ◽

Order Kinetic ◽

Adsorbent Dosage ◽

Initial Ph

In this study, the adsorption of methylene blue dye was examined by using pyrolusite ore as a low-cost alternative adsorbent source. Pyrolusite, which contains mainly MnO2, is a manganese ore. The effects of the initial concentration of dye, contact time, initial pH of solution, adsorbent dosage, stirring speed of solution, and average particle size of adsorbent on the adsorption of methylene blue were studied. It was found that the percentage of the adsorbed dye increased with increasing the amount of pyrolusite. While the initial dye concentration, initial pH, contact time, stirring speed, particle size, and adsorbent dosage were 25 ppm, 6, 90 min, 250 rpm, 63 µm, and 12 g/l, respectively, the efficiency of dye adsorption on pyrolusite ore was 99%. The isotherm and kinetic studies relating to this adsorption process were also made. It was found that the equilibrium data followed the Langmuir isotherm model while the kinetic of process could be described by the pseudo-second order kinetic model.

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Removal of Phosphate Ions from Aqueous Solutions by Adsorption onto Leftover Coal

Water ◽

10.3390/w12051381 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1381

Author(s):

Dereje Tadesse Mekonnen ◽

Esayas Alemayehu ◽

Bernd Lennartz

Keyword(s):

Experimental Data ◽

Aqueous Solutions ◽

Contact Time ◽

Aqueous Media ◽

Effect Of Temperature ◽

Phosphate Adsorption ◽

Operational Parameters ◽

Solution Ph ◽

Retention Efficiency ◽

Set Up

High loadings of wastewater with phosphors (P) require purification measures, which can be challenging to realize in regions where the technical and financial frame does not allow sophisticated applications. Simple percolation devices employing various kinds of adsorbents might be an alternative. Here, we investigated the application of leftover coal, which was collected from Ethiopian coal mining areas, as an adsorbent for the removal of phosphate from aqueous solutions in a classical slurry batch set-up. The combined effects of operational parameters such as contact time, initial concentration, and solution pH on P retention efficiency was studied employing the Response Surface Methodology (RSM). The maximum phosphate adsorption (79% removal and 198 mg kg−1 leftover coal) was obtained at a contact time of 200 min, an initial phosphate concentration of 5 mg/L, and a solution pH of 2.3. The Freundlich isotherm was fitted to the experimental data. The pseudo second-order equation describes the experimental data well, with a correlation value of R2 = 0.99. The effect of temperature on the adsorption reveals that the process is exothermic. The results demonstrate that leftover coal material could potentially be applied for the removal of phosphate from aqueous media, but additional testing in a flow-through set-up using real wastewater is required to draw definite conclusions.

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Removal of Azo Dyes (Violet B and Violet 5R) from Aqueous Solution Using New Activated Carbon Developed from Orange Peel

Journal of Chemistry ◽

10.1155/2013/283274 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Saeedeh Hashemian ◽

Khaterah Salari ◽

Hamila Salehifar ◽

Zahra Atashi Yazdi

Keyword(s):

Activated Carbon ◽

Contact Time ◽

Organic Dyes ◽

Agricultural Waste ◽

Orange Peel ◽

Polluted Water ◽

Order Kinetic ◽

Operational Parameters ◽

Freundlich Isotherms ◽

Order Kinetic Model

Activated carbon developed from agricultural waste orange peel (COP) was prepared. COP was characterized using Fourier infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and BET. COP has surface area and mean pore diameter of 225.6 m2 g−1and 22.40 nm, respectively. The removal of violet B (VB) and violet 5R (V5R) from aqueous solutions by COP was investigated. The effect of operational parameters such as contact time, pH, initial dye concentration, and adsorbent dosage on the adsorption of dyes was investigated. Maximum dye was removed within 30 min of contact time at pH > 7. Two common models, the Langmuir and Freundlich isotherms, were used to investigate the interaction of dye and COPs. The isotherm evaluations revealed that the Langmuir model provides better fit to the experimental data than the Freundlich model. The adsorption of VB and V5R onto COP was followed by pseudo-second-order kinetic model with a good correlation (R2>0.99). Activation energies 5.47 and 29.7 KJ mol−1were determined for violet B and violet 5R, respectively. The rate of adsorption of violet 5R was faster than that of violet B (kV5R>kVB). The prepared COP could thus be used as promising adsorbent for removal of organic dyes, especially azo dye, from polluted water. The solid COP could be conveniently regenerated after adsorption.

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Benzene Removal by Iron Oxide Nanoparticles Decorated Carbon Nanotubes

Journal of Nanomaterials ◽

10.1155/2016/5654129 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 14

Author(s):

Aamir Abbas ◽

Basim Ahmed Abussaud ◽

Ihsanullah ◽

Nadhir A. H. Al-Baghli ◽

Marwan Khraisheh ◽

...

Keyword(s):

Carbon Nanotubes ◽

Iron Oxide ◽

Iron Oxide Nanoparticles ◽

Contact Time ◽

Batch Adsorption ◽

Oxide Nanoparticles ◽

Order Kinetic ◽

Initial Concentration ◽

Adsorbent Dosage ◽

Benzene Removal

In this paper, carbon nanotubes (CNTs) impregnated with iron oxide nanoparticles were employed for the removal of benzene from water. The adsorbents were characterized using scanning electron microscope, X-ray diffraction, BET surface area, and thermogravimetric analysis. Batch adsorption experiments were carried out to study the adsorptive removal of benzene and the effect of parameters such as pH, contact time, and adsorbent dosage. The maximum removal of benzene was 61% with iron oxide impregnated CNTs at an adsorbent dosage 100 mg, shaking speed 200 rpm, contact time 2 hours, initial concentration 1 ppm, and pH 6. However, raw CNTs showed only 53% removal under same experimental conditions. Pseudo-first-order kinetic model was found well to describe the obtained data on benzene removal from water. Initial concentration was varied from 1 to 200 mg/L for isotherms study. Langmuir isotherm model was observed to best describe the adsorption data. The maximum adsorption capacities were 987.58 mg/g and 517.27 mg/g for iron oxide impregnated CNTs and raw CNTs, respectively. Experimental results revealed that impregnation with iron oxide nanoparticles significantly increased the removal efficiency of CNTs.

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Adsorption, Equilibrium and Kinetic Studies of the Removal of Methyl Violet from Aqueous Solution Using White Potato Peel Powder

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.80.17 ◽

2018 ◽

Vol 80 ◽

pp. 17-29 ◽

Cited By ~ 1

Author(s):

Conrad Kenechukwu Enenebeaku ◽

Ikechukwu C. Ukaga ◽

Nnaemeka John Okorocha ◽

Benedict Ikenna Onyeachu

Keyword(s):

Aqueous Solution ◽

Contact Time ◽

Methyl Violet ◽

Dye Adsorption ◽

Freundlich Isotherm ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Operational Parameters ◽

Potato Peel ◽

White Potato

The adsorption of methyl violet (MV) dye onto white potato Peel powder from aqueous solution was investigated by analyzing the operational parameters such as contact time, adsorbent dosage, initial dye concentration, PH and temperature to observe their effects in the dye adsorption process. The optimum conditions for the adsorption of MV onto the adsorbent (WPPP) was found to be contact time (120 mins), PH (10.0) and temperature (303K) for an initial MV dye concentration of 50mg/l and adsorbent dose of 1.0g. The experimental equilibrium adsorption data of the (MV) dye fitted best and well to the freundlich isotherm model. The maximum adsorption capacity was found to be 17.13mg/g for the adsorption of MV. The kinetic data conforms to the pseudo – second order kinetic model.

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