scholarly journals Response surface methodology for the optimization of acid dye adsorption onto activated carbon prepared from wild date stones

2019 ◽  
Vol 9 (8) ◽  
Author(s):  
Lamia Brahmi ◽  
Farida Kaouah ◽  
Salim Boumaza ◽  
Mohamed Trari

Abstract In the present study, wild date stones (WDS) were used as a novel and sustainable precursor for high-quality activated carbon preparation to be applied for the removal of Acid Blue 25 dye (AB25) from synthetic water. The carbonization temperature of the raw material was selected at 850 °C on the basis of thermo-gravimetric analysis. The adsorbents were characterized by the BET method, Fourier transform infrared spectroscopy, and scanning electron microscopy. The results indicated that the activated carbon presents a high specific surface area (610.84 m2 g−1) and a pore volume (0.224 cm3 g−1) compared with the natural material. Based on the central composite design, the effect of different parameters such as the biomass dose, initial dye concentration, contact time and temperature was optimized and the optimal removal of AB25 (99.61%) was achieved for AB25 concentration of 100 mg L−1 and an adsorbent dose of 0.8 g L−1, at 45 °C after 120 min. The kinetic studies indicated that the pseudo-second-order model was appropriately applied for the adsorption kinetic of AB25 onto wild date stones activated carbon. The intraparticle diffusion model is not the only controlling step, and other mechanisms may be involved in the adsorption process. The Langmuir isotherm provided the best fit with a high correlation coefficient (R2) of 0.993 and a maximum monolayer adsorption capacity of 181.59 mg g−1.

2010 ◽  
Vol 6 (2) ◽  
pp. 1017-1023
Author(s):  
N.R.A. El-Mouhty ◽  
H. M. H. Gad ◽  
A. Y. El-Naggar

This study investigated the applicability of chemically (phosphoric acid) activated bagasse pith and date pits in the adsorption of water pollutants. The textural properties including porous parameters, monolayer equivalent surface area, total pore volumes, average pore radius, Methylene blue number and other physic-chemical characterization were investigated. The activated carbons were analyzed for moisture content, ash content. Ultimate analysis was done by using CHNS analyzer (Cairo University, Micro-analytical Center). To investigate the effect of phosphoric acid on the raw material, thermo gravimetric analysis (TGA) and differential thermo gravimetric (DTG) recordings were determined. The adsorption of heavy metals as pollutants, including Co, Sr, Cu, Cs, Pb, Cd, Ni, Fe, Zn, was studied in a batch experiments. Comparison of date pits activated carbon with commercial activated carbon was done, and the results indicated that using of prepared activated carbon for removal of Co, Sr, Cu, Cs, Pb, Cd, Ni,  Fe, Zn was  more effective than commercial activated carbon.


2021 ◽  
Vol 36 (1) ◽  
pp. 16-24
Author(s):  
O. A. Ajayi ◽  
S Nanbyen ◽  
A. A Oladipo ◽  
F. U. Nwafulugo

MIL-53(Fe)/Cow bone char composite, prepared via the sol-gel method was used for the removal of chromium from real tannery effluent having an initial concentration of 40mg/l. The characteristics of MIL-53(Fe)/Cow bone char were studied using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA) Boehm titration and scanning electron microscopy (SEM-EDX). Adsorption capacity of MIL-53(Fe)/Cow bone char composite for chromium was 19.61 mg/g with a removal efficiency of 87.8% at an optimal bed height of 2.4cm (2.0g) for MIL-53(Fe)/Cow bone char composite, time of 2 minutes and pHpzc=5.4.The kinetic studies showed that the adsorption data were well fitted to the pseudo second-order model with high correlation coefficient R2=0.9911. Furthermore, the adsorption isotherm equilibrium studies confirmed that the Langmuir model best described the adsorption process of chromium onto MIL-53(Fe)/Cow bone char composite. Analysis of data with Dubinin–Radushkevich and Temkin isotherms showed that adsorption of chromium onto MIL-53(Fe)/Cow bone char composite is physical in nature.


2021 ◽  
Vol 5 (1) ◽  
pp. 364-371
Author(s):  
Yakubu Abdulkadir ◽  
K. A. Bichi ◽  
F. H. Garba ◽  
Y. C. Itopa ◽  
Y. U. Jibrin ◽  
...  

This study offers an integrated process for treatment and recycling of tannery waste, it has a dual purpose. First the activated carbon has been prepared from leather shaving and buffing dust by physical activation. Both the raw material (leather waste) and the prepared activated carbon were analyzed by DTG, Thermo Gravimetric Analysis TGA, and scanning electron microscope. The adsorption tests of methylene blue and iodine onto the raw material and the prepared adsorbent were carried out and it was found that the adsorption capacity of the activated carbon was enhanced by the physical activation. The Activated Carbon was then characterized by equation of Brunauer-Emmett-Teller surface area and Fourier transforms infrared spectroscopy (FTIR). The Brunauer-Emmett-Teller surface area was found to be 491.05 and 242.60 m2/g for activated carbons prepared from Leather Savings and Buffing Dust respectively and the functional groups on the adsorbent surface were mainly CN, NH, OH, CO and CS. Secondly, the performance of the prepared activated carbon was assessed by adsorption of chromium (VI) from a synthetic solution, and then the chromium (III) present in the tanning effluent. The results revealed a decrease of chromium by 76% and 73% for the activated carbons prepared from Leather Savings and Buffing Dust, respectively


2016 ◽  
Vol 22 (2) ◽  
pp. 167-179 ◽  
Author(s):  
Didem Özçimen ◽  
Tufan Salan

In this study, adsorbents were produced from sewage sludge via chemical and thermal activation processes. Experiments were carried out in a tubular furnace at the heating rate of 20?C min-1 and temperature of 550 ?C with a nitrogen flow rate of 400 mL min-1 for 1 h. Dye adsorption experiments were performed with Remazol Brilliant Blue R for its several concentrations under batch equilibrium conditions by comparing sewage sludge based adsorbents with raw material and a commercial activated carbon. Maximum adsorption capacities of carbonized sewage sludge (CSWS) and activated sewage sludge (ASWS) were found as 7.413 mg g-1 and 9.376 mg g-1 for 100 mg L-1 dye solution, whereas commercial activated carbon had a capacity of 11.561 mg g-1. Freundlich and Langmuir isotherms were used to explain the adsorption mechanism together with pseudo-first-order and pseudo-second-order kinetic models. Langmuir isotherm, which had adsorption capacities of 34.60 mg g-1 (CSWS) and 72.99 mg g-1 (ASWS), provided better fit to the equilibrium data than that of Freundlich isotherm. Pseudo second-order, model which had adsorption capacities of 7.451 mg g-1 (CSWS) and 9.319 mg g-1 (ASWS), was very favorable to explain the adsorption kinetics of the dye with high regression coefficients.


2009 ◽  
Vol 6 (3) ◽  
pp. 713-724 ◽  
Author(s):  
Y. Vijaya ◽  
A. Krishnaiah

As excess of fluoride (> 1.5 mg/L) in drinking water is harmful to the human health, various treatment technologies for removing fluoride from groundwater and aqueous medium have been investigated in the past. Present investigation aims to develop chitosan coated silica (CCS) and to investigate the removal of fluoride by CCS through adsorption. Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Thermo gravimetric analysis (TGA), X-ray diffraction (XRD) were used for the characterization of the sorbent. The surface morphology of the CCS was observed using SEM. Series of batch adsorption experiments were carried out to assess parameters that influence the adsorption process. The factors investigated include the influence of pH, contact time, adsorbent dose and initial fluoride concentration. The studies revealed there is an enhanced fluoride sorption on CCS. The sorption data obtained at optimized conditions were subjected to Langmuir and Freundlich isotherms. The monolayer sorption capacity, Q° (44.4 mg/g) and binding energy b (0.010 L/mg) have been estimated using Langmuir isotherm. The kinetic studies indicate that the sorption of fluoride on CCS follows Pseudo second-order kinetics.


2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Lingjie Liu ◽  
Min Ji ◽  
Fen Wang

Coconut granular activated carbon (CGAC) was modified by impregnating with ZnCl2solution to remove nitrate from aqueous solutions. Sorption isotherm and kinetic studies were carried out in a series of batch experiments. Nitrate adsorption of both ZnCl2-modified CGAC and CGAC fitted the Langmuir and Freundlich models. Batch adsorption isotherms indicated that the maximum adsorption capacities of ZnCl2-modified CGAC and CGAC were calculated as 14.01 mgN·g−1and 0.28 mgN·g−1, respectively. The kinetic data obtained from batch experiments were well described by pseudo-second-order model. The column study was used to analyze the dynamic adsorption process. The highest bed adsorption capacity of 1.76 mgN·g−1was obtained by 50 mgN·L−1inlet nitrate concentration, 20 g adsorbents, and 10 ml·min−1flow rate. The dynamic adsorption data were fitted well to the Thomas and Yoon–Nelson models with coefficients of correlationR2 > 0.834 at different conditions. Surface characteristics and pore structures of CGAC and ZnCl2-modified CGAC were performed by SEM and EDAX and BET and indicated that ZnCl2had adhered to the surface of GAC after modified. Zeta potential, Raman spectra, and FTIR suggested the electrostatic attraction between the nitrate ions and positive charge. The results revealed that the mechanism of adsorption nitrate mainly depended on electrostatic attraction almost without any chemical interactions.


2015 ◽  
Vol 6 (2) ◽  
pp. 310-324 ◽  
Author(s):  
Selvaraj Dinesh Kirupha ◽  
Selvaraj Kalaivani ◽  
Thangaraj Vidhyadevi ◽  
Periyaraman Premkumar ◽  
Palanithamy Baskaralingam ◽  
...  

A novel poly [2,5-(1,3,4-thiadiazole)-benzalimine] abbreviated as TDPI adsorbent was synthesized using simple polycondensation technique. The synthetic route involves the preparation of 2,5-diamino-1,3,4-thiadiazole from 2,5-dithiourea and subsequent condensation with terephthalaldehyde. The resin was chemically characterized using Fourier transform infrared (FT-IR), 1H-NMR, and 13C-NMR spectroscopic analysis. Surface morphology and thermal stability were analyzed using scanning electron microscopy (SEM) and thermo-gravimetric analysis (TGA). The effect of the pH value of solution, contact time, adsorbent dose, and initial metal ion concentration were investigated by batch equilibrium adsorption experiments. Kinetic studies show that the adsorption of metal ions onto the resin proceeds according to the pseudo-second-order model and the equilibrium data were best interpreted by the Redlich–Peterson isotherm. The experimental values of the adsorption capacities of Pb2+, Cu2+, Ni2+, and Cd2+ on to TDPI could reach up to 437.2, 491.6, 493.7, and 481.9 mg.g−1 respectively. The exothermic nature of the process, the affinity of the adsorbent towards the metal ions and the feasibility of the process are explained in the thermodynamic parameters. The resin stability and re-usability studies suggest that the resin is chemically stable (0.3 N HCl and H2SO4) and could be regenerated without any serious decline in performance.


2014 ◽  
Vol 979 ◽  
pp. 315-318 ◽  
Author(s):  
W. Siriprom ◽  
K. Chantarasunthon ◽  
K. Teanchai

This work aims at characterizing the thermal and physical properties of chitosan. The samples were evaluated for potentiality to use as raw material for biodegradable films raw material. Their thermal and physical properties have been also discussed in detail which Fourier Transform Infrared Spectroscopy (FTIR), Thermo-Gravimetric Analysis (TGA), Energy Dispersive X-Ray Fluorescence (EDXRF) and X-Ray Diffraction (XRD), respectively. The result of the XRD pattern indicated the sample has amorphous-crystalline structure and FTIR results confirmed the formation of intermolecular hydrogen bonding between the amino and hydroxyl groups of the sample. In good agreement between the EDXRF and TGA results, noticed that the removal of moisture and volatile material.


2017 ◽  
Vol 77 (3) ◽  
pp. 628-637 ◽  
Author(s):  
Shuangzhen Guo ◽  
Jian Zhang ◽  
Xianlong Li ◽  
Fan Zhang ◽  
Xixi Zhu

Abstract A novel core-shell bio-adsorbent was fabricated by using biological materials for removing methyl orange (MO) from aqueous solution. The structure characteristics results of scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FT-IR), thermo-gravimetric analysis (TGA), vibrating sample magnetometer (VSM), and Brunauer–Emmett–Teller (BET) shows that Fe3O4-CS-L has been successfully prepared. The effects of contact time, pH, temperature and initial concentration were explored. The results suggested pH was a negligible factor in adsorption progress. Kinetic studies showed that the experiment data followed pseudo-second-order model. Boyd mode suggested that external mass transfer showed a rather weak rate control for MO adsorption onto Fe3O4-CS-L. Equilibrium studies showed that isotherm data were the best described by Langmuir model. The maximum adsorption capacity of MO estimated to be 338.98 mg/g at 298 K. Moreover, the adsorption capacity of Fe3O4-CS-L can keep about 74% in the fifth adsorption–regeneration cycle. Thus, the Fe3O4-CS-L could be a kind of promising material for removing MO from wastewater.


2014 ◽  
Vol 1043 ◽  
pp. 219-223 ◽  
Author(s):  
Noor Shawal Nasri ◽  
Jibril Mohammed ◽  
Muhammad Abbas Ahmad Zaini ◽  
Usman Dadum Hamza ◽  
Husna Mohd. Zain ◽  
...  

Concern about environmental protection has increased over the years and the presence of volatile organic compounds (VOCs) in water poses a threat to the environment. In this study, coconut shell activated carbon (PHAC) was produced by potassium hydroxide activation via microwave for benzene and toluene removal. Equilibrium data were fitted to Langmuir, Freundlich and Tempkin isotherms with all the models having R2 > 0.94. The equilibrium data were best fitted by Langmuir isotherm, with maximum adsorption capacity of 212 and 238mg/g for benzene and toluene, respectively. The equilibrium parameter (RL) falls between 0 and 1 confirming the favourability of the Langmuir model. Pseudo-second-order kinetic model best fitted the kinetic data. The PHAC produced can be used to remediate water polluted by VOCs.


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