scholarly journals Platinum Nanoparticles Loaded on Activated Carbon as Novel Adsorbent for the Removal of Congo Red

2012 ◽  
Vol 9 (1) ◽  
pp. 63-74 ◽  
Author(s):  
M. Ghaedi ◽  
S. J. Hossaini ◽  
S. Ramezani

Platinum nanoparticles loaded on activated carbon as novel adsorbent was successfully applied for efficient removal of congo red. The influences of effective parameters including contact time, pH and temperature, amount of adsorbents and concentration of initial dye on the efficiency of removal of congo red from aqueous solution were investigated. Adsorption experiments indicate that the extent of adsorption is strongly dependent on pH of solution. Thermodynamic parameters like Free energy of adsorption, enthalpy and entropy changes were calculated to know the nature of adsorption. The calculated values of free energy of adsorption (negative value) indicate that the adsorption process is spontaneous. The estimated values of enthalpy and entropy both show the positive sign, which indicate that the adsorption process is endothermic and the dye molecules are organized on the adsorbent surface in more randomly fashion than in solution. Fitting experimental data to different kinetic models including first order, pseudo second order and Elovich and intra-particle diffusion models shows that the rate of dye adsorption follows pseudo second order model and involvement of intera- particle diffusion mechanism.

Author(s):  
Li Cong ◽  
Lingling Feng ◽  
Xinlai Wei ◽  
Jie Jin ◽  
Ke Wu

The activated carbon was prepared from sycamore bark by activation of zinc chloride. The absorbing effect of activated carbon on Congo red wastewater is studied. The characteristics of sycamore bark activated carbon were characterized by SEM and BET. The effects of adsorbent dosage, time, and shaking speed on the adsorption properties of Congo red by sycamore bark activated carbon were studied. The isotherm, kinetics, and thermodynamics of adsorption were explored. The results revealed that the activated carbon contain a large apparent mesopores. Adsorption efficiency was increased with enhancing the adsorption dosage and time. The removal rate of Conge red reached to 98.2% under room temperature with adsorbent dosage of 3.0 g/L, adsorption time of 120 min, shaking speed of 60r/min. The adsorption of Congo red on sycamore bark activated carbon was followed Langmuir isotherm model and Lagergren pseudo-second order kinetics model. The adsorption was spontaneous, endothermic, and the entropy was increasing in the adsorption process.


2019 ◽  
Vol 79 (7) ◽  
pp. 1357-1366 ◽  
Author(s):  
Rabia Boudia ◽  
Goussem Mimanne ◽  
Karim Benhabib ◽  
Laurence Pirault-Roy

Abstract This work concerns the elimination of the organic pollutant; Bemacid Red (BR), a rather persistent dye present in wastewater from the textile industry in western Algeria, by adsorption on carbon from an agricultural waste in the optimal conditions of the adsorption process. An active carbon was synthesized by treating an agro-alimentary waste, the date stones that are very abundant in Algeria, physically and chemically. Sample after activation (SAA) with phosphoric acid was highly efficient for the removal of BR. The characterization of this porous material has shown a specific surface area that exceeds 900 m2/g with the presence of mesopores. The iodine value also indicates that the activated carbon obtained has a large micro porosity. The reduction of the infrared spectroscopy (FTIR) bands reveals that the waste has been synthesized and activated in good conditions. Parameters influencing the adsorption process have been studied and optimized, such as contact time, adsorbent mass, solution pH, initial dye concentration and temperature. The results show that for a contact time of 60 min, a mass of 0.5 g and at room temperature, the adsorption rate of the BR by the SAA is at its maximum. Pseudo-first-order, pseudo-second-order and intraparticle diffusion models were studied to analyse adsorption kinetics. The result shows the adsorption kinetic is best with the pseudo-second-order model. In this study, Langmuir, Freundlich and Temkin isotherms were investigated for adsorption of BR onto SAA. The Freundlich and Temkin isotherms have the highest correlations coefficients. The suggested adsorption process involves multilayer adsorption with the creation of chemical bonds. The mechanism of adsorption of BR by SAA is spontaneous and exothermic, and the Gibbs free energy values confirm that the elimination of the textile dye follows a physisorption.


2014 ◽  
Vol 1073-1076 ◽  
pp. 955-959
Author(s):  
Ruo Zheng Li ◽  
Hong Yang ◽  
Xin Jin

Lignite activated carbon was provided through lignite which is treated specially. The adsorption capacity and mechanism of COD from Coal gasification wastewater by lignite activated carbon have been studied.The adsorption capacities of lignite activated carbon at different times were obtained by concentration of COD in the remainder solution. Three simplified kinetic models: pseudo-first-order, pseudo-second-order, intraparticle diffusion equations were adopted to examine the mechanism of the adsorption process. The results showed that the adsorption can be expressed by the pseudo-second-order model. The adsorption balance capacity was obtained as 50.8mg·g-1 (298K), and the adsorption balance capacity decreased with increasing of temperature, which showed that the adsorption process was exothermic. The adsorption activation energy (Ea) was calculated as 5.76kJ·mol-1, and it showed that the adsorption process was Physical adsorption. This study explored new treatment channels for lignite comprehensive utilization..


2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Y. El maguana ◽  
N. Elhadiri ◽  
M. Benchanaa ◽  
R. Chikri

Batch adsorption experiments have been conducted to investigate the removal of methyl orange from aqueous solution by an activated carbon prepared from prickly pear seed cake by phosphoric acid activation. The adsorption process has been described by using kinetic and isotherm models. The kinetic of adsorption was examined by pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. Adsorption isotherm was modeled using Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherms. The adsorption process of methyl orange was well explained by the pseudo-second-order model and Freundlich isotherm. Also, pseudo-n-order model has been applied to estimate the order of adsorption kinetic and it was found equal to 2 which confirm the good accuracy of the pseudo-second order. Moreover, Dubinin–Radushkevich isotherm reveals that the adsorption of methyl orange onto activated carbon was a physisorption process in nature. The adsorption capacity of activated carbon was found to be 336.12 mg/g at temperature 20°C and pH∼7. These results demonstrated that the prickly pear seed cake is a suitable precursor for the preparation of appropriate activated carbon for dyes removal from aqueous solution.


Author(s):  
Abdelkader Ouakouak ◽  
Leila Youcef ◽  
Djihad Boulanouar ◽  
Samia Achour

The objective of this work is to study the phosphate adsorption from natural waters by using a granular activated carbon (GAC). Experiments were carried out with synthetic solutions of phosphate prepared using groundwater (mineralized drinking water). Batch tests were carried out in order to study different operating parameters such as the effect of contact time, pH, initial phosphate concentration and adsorbent dosage. In addition, the adsorption kinetic data were simulated using the pseudo first order, the pseudo second-order and the intra-particle diffusion model. The sorption equilibrium was analyzed by Langmuir, Freundlich and Dubinin–Radushkevich isotherms model. Results show that the phosphate adsorption was reversible and the quantity adsorbed reached its maximum value (2.82 mg/g) after 30 min. It was also found that phosphate uptake was affected by variation of pH, initial concentration of phosphate and granular activated carbon dosage. The adsorption improved with increase in pH values, initial concentration and adsorbent dosage. The results of kinetic studies revealed that pseudo-second-order model adequately described the adsorption phosphate on GAC and the intra-particle diffusion involved in the adsorption mechanism. Also, isotherm study showed that Langmuir isotherm best fit the data and the adsorption was a physical type.


2015 ◽  
Vol 17 (4) ◽  
pp. 784-795 ◽  

<div> <p>Low cost agricultural waste adsorbents can be viable alternatives to activated carbon for the treatment of contaminated wastewater. Sugarcane Bagasse, an abundant agriculture waste in Egypt, was used in the present study to prepare activated carbon. Batch adsorption experiments were conducted to study its effectiveness to remove cationic dye methylene blue from aqueous solution. The effects of initial dye concentrations, agitation time, solution pH and temperature on methylene blue dye removal were investigated. The optimum pH value for the maximum percentage removal of the dye was 7. Adsorption isotherms were determined and modeled with Redlich&ndash;Peterson, Langmuir and Freundlich equations at 20&ordm;C.The kinetic data were analyzed using Pseudo-first order, pseudo-second order. The mechanism of the adsorption process was determined from the intraparticle diffusion model. Thermodynamic parameters such as standard enthalpy (ΔH&deg;), standard entropy (ΔS&deg;) and free energy (ΔG&deg;) were determined.&nbsp; The equilibrium data were best fitted to the Redlich&ndash;Peterson isotherm model .The adsorption kinetics was found to follow the pseudo-second-order kinetic model with good correlation coefficient. The positive ΔH<sup>◦</sup> value indicated that the adsorption process was endothermic in nature. The results revealed sugarcane bagasse activated carboncould be employed as a low-cost alternative adsorbent in wastewater treatment.&nbsp;</p> </div> <p>&nbsp;</p>


REAKTOR ◽  
2019 ◽  
Vol 19 (2) ◽  
pp. 68-76
Author(s):  
Fahriya Puspita Sari ◽  
Dede Heri Yuli Yanto ◽  
Gustan Pari

Activated carbon was prepared from OPEFB by one step steam activation method. The adsorption performance for the removal of acid orange 52 (AO 52), reactive blue 19 (RB 19), basic violet 1 (BV 1) was investigated. Each dye has a different chemical structure such as azoic, anthraquinone, triarylmethane for AO 52, RB 19, and BV 1 respectively. The effects of adsorbent dosage, pH, and contact time on the adsorption process were studied. Experimental data were analyzed by model equations such as Langmuir, Freundlich and Temkin isotherms and it was found that the Langmuir isotherm model best fitted for all three dyes with R2 values is higher than 0.95. Langmuir model assumes a homogeneous nature and monolayer coverage of dye molecules at the outer surface of activated carbon. Adsorption kinetics was determined using pseudo-first-order, pseudo-second-order rate equations, Elovich model and also intraparticle diffusion models. Kinetic studies showed that the pseudo-second-order kinetic model better described the adsorption process with R2 values exceeds 0,99 compared with the other kinetics model. The SEM images showed AC pores was well developed with steam activation while wider porosity is created in the macropore range. FT-IR analysis had shown that the AC functional groups were disappeared because of vaporization the volatile materials when the heating process. Keywords: Activated Carbon, Adsorption Isotherms, Kinetic, OPEFB, Steam Activation


2019 ◽  
pp. 12-20
Author(s):  
Ezeh Ernest ◽  
Okeke Onyeka ◽  
Aburu C. M. ◽  
Aniobi C. C. ◽  
Ndubuisi J. O

Studies were carried out to evaluate the adsorption efficiency of activated carbon produced from corn cob for the removal of Cd II ions from aqueous solution. The studies were carried out with due consideration of standard analytical procedures and instrumentation. Increase in the Cd II ions concentration from 90 to 180mg/l decreased the adsorption capacity of the adsorbent from 89.273 to 65.770%. Increase in the adsorbent’s dosage from 0.5 to 2.0g increased the adsorption of Cd II ions from 81.522 to 91.980%. At pH of 5.0, the adsorption process attained equilibrium with a peak adsorption of Cd II ion at 93.628%. At a contact of time of 30mins between the adsorbate (Cd II ions) at the adsorbent; the adsorption of Cd II ions reached a peak value of 92.410%. The adsorption of Cd II ions on the surface of the activated carbon increased from 90.436 to 93.210% with increase in temperature from 40o to 160oC. The decrease in Gibb’s free energy of adsorption of Cd II ions on the surface of the activated carbon revealed that the adsorption was favourable at high temperatures. The positive values of ∆H and ∆S shows that the adsorption process was endothermic.


2013 ◽  
Vol 864-867 ◽  
pp. 1536-1541
Author(s):  
Yu Wu ◽  
Li Li Zhao ◽  
Jiang Wu ◽  
Yin Xia Cao ◽  
Jia Ming Zha ◽  
...  

Two types of activated carbon for the removal of element mercury in simulated flue gas were studied in the paper. Mercury adsorption process on fixed bed reactor has been researched. The conclusions are as follows: The trend of mercury concentration first decreased and then increased over time; as for two types of activated carbon, the adsorption corresponds to pseudo-first-order equation and pseudo-second-order equation respectively. Because of the high correlation coefficient, the pseudo-second-order equation will correspond to actual adsorption process.


2020 ◽  
Vol 13 (1) ◽  
pp. 12-20
Author(s):  
Azhaar Radhi Jabbar

This research includes a lab scale work to investigate the feasibility of treating waste water which polluted with dyes exhausted from textile factory by using adsorption process. Three type of activated carbon were prepared using locally available waste material (date stone). Chemical activation method  with (zinc chloride, potassium hydroxide, or phosphoric acid) was used  as activators  to  prepared carbon. Firstly, the materials were carbonized at 275 oC for 90 min and then the carbonized materials were treated with (4 molar) solution of acid, base or salt for 24 hour. Finally, these materials were activated at 600 oC for two hours in the presence of nitrogen gas flow. The resulted activated carbons were checked by its (BET) surface area analysis and surface morphology by SEM. The surface area values were (815, 950,600) m2/g for carbon produced from the activation of date  stone by phosphoric acid, potassium hydroxide or zinc chloride respectively. SEM characterizations show that activated carbons that prepared from potassium hydroxide have higher surface area and good adsorption characteristics than that prepared from activation with phosphoric acid or zinc chloride. The  adsorption process was studied using two types of dyes. The first one is acidic (methyl orange) and the other is basic (bismark brown). The adsorption isotherms and kinetics where investigated for both dyes at temperatures (30,40,50,60)oC for concentration  range  equal to (6-16)mg/l.  The  adsorption data of equilibrium were presented by using two common adsorption isotherm equations. The data was fitted fairly well with Langmuir isotherm for both dyes on all types of prepared activated carbons. The kinetic of adsorption was study by using two kinetic equations, pseudo first order and pseudo second order. The result showed the rapid increase in the rate of adsorption at the initial until equilibrium achieved. Pseudo second order model were represent the data very well with confidence level 0.99.


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