scholarly journals Removal of the pesticide methomyl contained in simulated effluent from equipment washing by adsorption in residual orange bagasse

2020 ◽  
Vol 9 (11) ◽  
pp. e3569118528
Author(s):  
Thiago Ruiz Zimmer ◽  
Jailton Marques Silva ◽  
Diego Henrique de Aquino Rocha ◽  
Helder Lopes Teles ◽  
Domingos Sávio Barbosa ◽  
...  

This work consists of the study of methomyl removal, an extremely toxic carbamate pesticide, contained in aqueous solutions synthesized, by adsorption in residual orange bagasse from industrial juices processing. The adsorption kinetics was studied by obtaining the best fit for the model of pseudo-second order (R2= 0.949). The Langmuir isotherm model adjusted better to the experimental data confirming the adsorption in monolayers, without interaction among the adsorbate molecules. The scanning electron microscopy (SEM) revealed that particulate adsorbents have rather irregular surface, but with rigid structure and virtually no internal pores. The characterization of the functional groups by infrared spectroscopy (FTIR) revealed the presence of hydroxyl, Carbonyl and carboxylic groups on the adsorbents particles surface. Central composite rotational design 2x2 (DCCR 2x2) was used for the statistical study of the effects of pH and solid/liquid ratio (R) on the methomyl adsorption capacity in orange bagasse particles. The obtained mathematical model adjusted well to the experimental data (R2= 95%). In the studied intervals the highest values of adsorption capacity (q) were 3.73 and 3.43 (mg.g-1), obtained under the conditions of pH 6.0 with R 0.017 g.mL-1 and pH 4.5 with R 0.015 g.mL-1, respectively. Thus, it was possible to conclude that there was a greater adsorption in assays containing greater adsorbent mass in pH slightly acid.

Author(s):  
Joshua O. Ighalo ◽  
Ibrahim O. Tijani ◽  
Oluwaseun J. Ajala ◽  
Fisayo O. Ayandele ◽  
Omodele A. Eletta ◽  
...  

Background: Modified bio-based adsorbents from plant sources can be used for pollution remediation by adsorption due to their low cost and availability in large quantities. Objective: In this study, the competitive biosorption of Pb(II) and Cu(II) by Micropogonias undulates functionalised fish scales (FFS) was conducted. The functionalisation was done by wet impregnation with Fe2+. Method: The biosorbent was characterised by Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy with Energy-Dispersive X-ray Spectroscopy (SEM-EDS) and Branueur–Emmett–Teller (BET) analyses. Results: The major constituents in the FFS were calcium and phosphorus from the collagen and apatite on the scales. Optimum removal efficiency for both metals was >99% at 10 g/l dosage. It was observed that the Langmuir isotherm model and the pseudo second order kinetics model were the best fit for the experimental data. The monolayer adsorption capacity of FFS for Pb(II) and Cu(II) was observed to be 96.15 mg/g and 100 mg/g respectively. Conclusion: The study revealed that the competitive biosorption of heavy metals can be achieved (at a good adsorption capacity) using functionalised Micropogonias undulates fish scales.


2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Ghorban Asgari ◽  
Bahman Ramavandi ◽  
Sima Farjadfard

We introduce a new adsorbent, bimetallic chitosan particle (BCP) that is successfully synthesized and applied to remove the orange II dye from wastewater. The effects of pH, BCP quantity, and contact time are initially verified on the basis of the percentage of orange II removed from the wastewater. Experimental data reveal that the Cu/Mg bimetal and chitosan have a synergistic effect on the adsorption process of the adsorbate, where the dye adsorption by Cu/Mg bimetal, chitosan alone, and bimetal-chitosan is 10, 49, and 99.5%, respectively. The time required for the complete decolorization of orange II by 1 mg/L of BCP is 10 min. The Langmuir model is the best fit for the experimental data, which attains a maximum adsorption capacity of 384.6 mg/g. The consideration of the kinetic behavior indicates that the adsorption of orange II onto the BCP fits best with the pseudo-second-order and Elovich models. Further, the simulated azo dye wastewater can be effectively treated using a relatively low quantity of the adsorbent, 1 mg/L, within a short reaction time of 20 min. Overall, the use of BCP can be considered a promising method for eliminating the azo dye from wastewater effectively.


2014 ◽  
Vol 937 ◽  
pp. 276-281 ◽  
Author(s):  
Qi Lin Cao ◽  
Yuan Meng Zhao ◽  
Xiang Yan Wei ◽  
Fang Luo

Cornstalk, a cellulosic agricultural waste material, was modified by citric acid to improve the adsorption of rhodamine B (RB) and methylene blue (MB) from aqueous media. Characterization of SEM and FTIR spectra confirmed that the surface morphology of adsorbent changed and carboxylic groups were introduced into the raw cornstalk by chemical modification. The effects of pH, contact time, initial concentration and the amount of dried adsorbent were studied in batch experiments. There was no significant difference in the dye concentration remaining when the pH was increased from 4.0 to 10.0. Several models were used to fit experimental data and the results showed that experimental data fitted the Langmuir model and pseudo-second order model best. Compared with 58.71 and 81.71 mg g-1obtained by CS (raw cornstalk), the maximum adsorption capacities for RB and MB were 203.0 and 245.6 mg g-1by using CCS (cornstalk modified with citric acid), respectively.


2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Jhonatan R. Guarín ◽  
Juan Carlos Moreno-Pirajan ◽  
Liliana Giraldo

Currently, there is a great pollution of water by the dyes; due to this, several studies have been carried out to remove these compounds. However, the total elimination of these pollutants from the aquatic effluents has represented a great challenge for the scientific community, for which it is necessary to carry out investigations that allow the purification of water. In this work, we studied the bioadsorption of methylene blue on the surface of the biomass obtained from the algae D. antarctica. This material was characterized by SEM and FTIR. To the data obtained in the biosorption experiments, different models of biosorption and kinetics were applied, finding that the best fit to the obtained data is given by applying the pseudo-second-order models and the Toth model, respectively. It was also determined that the maximum adsorption capacity of MB on the surface of the biomass is 702.9 mg/g, which shows that this material has great properties as a bioadsorbent.


2012 ◽  
Vol 550-553 ◽  
pp. 2259-2262
Author(s):  
Song Bo Cui ◽  
Hua Yong Zhang ◽  
Lu Yi Zhang

The adsorption behavior of methylene blue (MB) dye from aqueous solutions onto honeycomb-cinder (HC) and its acid-activated product was investigated in a batch system. The results showed the adsorption capacity was decreased for raw HC samples with the increase of pH value, while it was increased for activated samples. The adsorption data were fit with Langmuir isotherm model for MB adsorption by all samples. The MB adsorption capacity on samples was increased from 2.62 mg/g to 7.81 mg/g and 7.00 mg/g after acid-activated by HCl and H2SO4, respectively. The adsorption processes of MB followed pseudo-second-order kinetics with a coefficient of correlation≥0.99. This study demonstrated that acid-activated HC has superior adsorbing ability for MB than raw HC and can be used as alternative adsorbents in dye wastewater treatment.


2021 ◽  
Author(s):  
khaled Mostafa ◽  
H. Ameen ◽  
A. Ebessy ◽  
A. El-Sanabary

Abstract Our recently tailored and fully characterized poly (AN)-starch nanoparticle graft copolymer having 60.1 G.Y. % was used as a starting substrate for copper ions removal from waste water effluent after chemical modification with hydroxyl amine via oximation reaction. This was done to change the abundant nitrile groups in the above copolymer into amidoxime one and the resultant poly (amidoxime) resin was used as adsorbent for copper ions. The resin was characterized qualitatively via rapid vanadium ion test and instrumentally by FT-IR spectra and SEM morphological analysis to confirm the presence of amidoxime groups. The adsorption capacity of the resin was done using the batch technique, whereas the residual copper ions content in the filtrate before and after adsorption was measured using atomic adsorption spectrometry. It was found that the maximum adsorption capacity of poly (amidoxime) resin was 115.2 mg/g at pH 7, 400ppm copper ions concentration and 0.25 g adsorbent at room temperature. The adsorption, kinetics and isothermal study of the process is scrutinized using different variables, such as pH, contact time, copper ion concentration and adsorbent dosage. Different kinetics models comprising the pseudo-first-order and pseudo-second-order have been applied to the experimental data to envisage the adsorption kinetics. It was found from kinetic study that pseudo-second-order rate equation was better than pseudo-first-order supporting the formation of chemisorption process. While, in case of isothermal study, the examination of calculated correlation coefficient (R2) values showed that the Langmuir model provide the best fit to experimental data than Freundlich one.


2017 ◽  
Vol 82 (4) ◽  
pp. 449-463 ◽  
Author(s):  
Sanja Marinovic ◽  
Marija Ajdukovic ◽  
Natasa Jovic-Jovicic ◽  
Tihana Mudrinic ◽  
Bojana Nedic-Vasiljevic ◽  
...  

Bentonites from three different deposits (Wyoming, TX, USA and Bogovina, Serbia) with similar cation exchange capacities were sodium enriched and tested as adsorbents for Sr2+ in aqueous solutions. X-Ray diffraction analysis confirmed successful Na-exchange. The textural properties of the bentonite samples were determined using low-temperature the nitrogen physisorption method. Significant differences in the textural properties between the different sodium enriched bentonites were found. Adsorption was investigated with respect to adsorbent dosage, pH, contact time and the initial concentration of Sr2+. The adsorption capacity increased with pH. In the pH range from 4.0?8.5, the amount of adsorbed Sr2+ was almost constant but 2?3 times smaller than at pH ?11. Further experiments were performed at the unadjusted pH since extreme alkaline conditions are environmentally hostile and inapplicable in real systems. The adsorption capacity of all the investigated adsorbents toward Sr2+ was similar under the investigated conditions, regardless of significant differences in the specific surface areas. It was shown and confirmed by the Dubinin?Radushkevich model that the cation exchange mechanism was the dominant mechanism of Sr2+ adsorption. Their developed microporous structures contributed to the Sr2+ adsorption process. The adsorption kinetics obeyed the pseudo-second-order model. The isotherm data were best fitted with the Langmuir isotherm model.


2014 ◽  
Vol 70 (4) ◽  
pp. 678-684 ◽  
Author(s):  
Jun Chen ◽  
Xiaoqin Hong ◽  
Yongteng Zhao ◽  
Qianfeng Zhang

Exfoliated polyaniline/montmorillonite (PANI/MMT) composites with nanosheet structure were successfully prepared by in situ chemical oxidation polymerization with MMT platelets as the scaffold. Amphoteric polymer, (2-methacryloyloxyethyl)trimethyl ammonium chloride and methacrylate acid copolymer, was used to modify montmorillonite and a large number of carboxylic acids were introduced on the surface of the clay platelets, which can be used as a dopant of PANI and play a ‘bridge’ role to combine PANI with clay. Adsorption experiments were carried out to study the effects of pH, contact time, Cr(VI) concentration, adsorbent dose and temperature. The adsorption of Cr(VI) on the PANI/MMT was highly pH dependent and the adsorption kinetics followed a pseudo-second-order model. The Langmuir isothermal model described the adsorption isotherm data well and the maximum adsorption capacity increased with the increase in temperature. Thermodynamic investigation indicated that the adsorption process is spontaneous, endothermic and marked with an increase in randomness at the adsorbent – liquid interface. The maximum adsorption capacity of the PANI/MMT composites for Cr(VI) was 308.6 mg/g at 25 °C. The excellent adsorption characteristic of exfoliated PANI/MMT composites will render it a highly efficient and economically viable adsorbent for Cr(VI) removal.


2020 ◽  
Vol 32 (7) ◽  
pp. 1549-1556
Author(s):  
Abdulaziz Ali Alomari

The aim of this work is to investigate the use of eggshell for adsorption of Cr(VI) from aqueous solution and the effect of thermal treatment as well as coating with Fe2O3 of eggshell on the extraction percent of Cr(VI). The XRD, FTIR and SEM techniques proved that the eggshell mainly composed of calcite rhombohedral structure in addition to a trace of quartz silica residual protein fibers. Heating at 550 ºC does not decompose eggshell but decomposes the residual protein. The effect of pH, weight of eggshell adsorbent, contact time, and initial concentration of Cr(VI) ions on the adsorption of Cr(VI) on eggshell sorbents were determined under static conditions by the batch equilibrium technique. The sorption kinetic as well as mechanistic isotherm parameters of Cr(VI) on the eggshell sorbent, were analyzed. It was concluded that the adsorption of Cr(VI) on eggshell increases as pH increases in the range 3-7, then, with decreases at higher pH. The extraction percent of Cr(VI) increases with an increase in the dosage of eggshell sorbents. The optimum dosage of eggshell adsorbents was found to be 5 g after which the extraction percent of Cr(VI) did not marked increase. The extraction percent of Cr(VI) by eggshell sorbents rapidly increases within 60 min followed by a slower extraction after that when maximum adsorption was reported. The adsorption capacity of Cr(VI) ions is slightly reduced in case of heated eggshell due to the change that occurs in the pore size distribution and structure of eggshell during heating. Hence, the thermal treatment and coating with Fe2O3 do not affect the chemical structure of eggshell sorbents. The adsorption kinetics data were best fitted with the pseudo-second-order equation and the adsorption isotherms were best fitted with the Langmuir isotherm model.


Author(s):  
Bo Wang ◽  
Jie Yu ◽  
Hui Liao ◽  
Wenkun Zhu ◽  
Pingping Ding ◽  
...  

A novel natural honey hydrothermal biochar (HHTB) was prepared using natural honey as raw material. The as-prepared adsorbent was applied to adsorb Pb2+ from aqueous solution and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy to investigate the structure and morphology change of the adsorbent before and after Pb2+ adsorption. The influence of the pH, initial Pb2+ concentration, temperature, and contact time on the adsorption of Pb2+ was systematically investigated. The results revealed that the adsorption capacity for Pb2+ is up to 133.2 mg·g−1 at initial pH of 5.0 and adsorption temperature of 298 K. Meanwhile, the adsorption of Pb2+ on HHTB can be well fitted by the pseudo-second-order model and Langmuir isotherm model. The adsorbent had great selectivity for Pb2+ from the aqueous solution containing coexisting ions including Cd2+, Co2+, Cr3+, Cu2+, Ni2+ and Zn2+. Furthermore, the adsorption of Pb2+ on HHTB was attributed to complexation coordination, where it involved hydroxyl and carboxylic groups on HHTB in the process of adsorption of Pb2+.


Sign in / Sign up

Export Citation Format

Share Document