Study on Removal of Humic Acid by Polyurethane Foam/ Activated Carbon Composites in Boiler Feedwater

2010 ◽  
Vol 26-28 ◽  
pp. 452-456
Author(s):  
Zhi Ping Zhu ◽  
Ke Long Huang ◽  
Yi Zhou
Keyword(s):  
Activated Carbon ◽  
Humic Acid ◽  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
High Efficiency ◽  
Removal Rate ◽  
Equilibrium Adsorption ◽  
Batch Adsorption ◽  
Equilibrium Adsorption Capacity ◽  
Boiler Feedwater

A new type and high efficiency adsorbent was prepared with powder activated carbon and polyurethane vesicant and surfactant, which being used to adsorb humic acid (HA) in boiler feedwater. The batch adsorption experiments were carrid at different pH value, different adsorbent dosage and different initial concentration to investigate HA removal rate and adsorption capacity by as-produced adsorbent. Their adsorption kinetics experiments data was fitted with pseudo-second-order rate model, its quation was 1/qt=0.094+5.51/t, and equilibrium adsorption capacity obtained from fitting curve was 10.6mg/g, consistent with the experimental results(11.5mg/g).The adsorption isotherm test was carried at 25°C-50°C, the equilibrium adsorption capacity was 10.9mg/g by Langmuir model, which being similar with experiment results, the free energy (ΔG), enthalpy(ΔH) and entropy (ΔS) were obtanined with Clapeyron-Clausius and Gibbs-Helmholtz equation in the adsorption isotherm, which all were negative, indicated that HA adsorbed by as-produced adsorbent was an exothermic process of entropy reduction.

scholarly journals Kinetics of Phenol Removal from Aqueous Solution by Adsorption onto Peanut Shell Acid-Activated Carbon

2005 ◽  
Vol 23 (4) ◽  
pp. 289-302 ◽  
Author(s):  
Elio E. Gonzo ◽  
Luis F. Gonzo
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Rate Constant ◽  
Equilibrium Adsorption ◽  
Phenol Removal ◽  
Peanut Shell ◽  
Pseudo Second Order ◽  
Equilibrium Adsorption Capacity ◽  
Initial Adsorption ◽  
Initial Adsorption Rate

A pseudo-second-order rate equation describing the kinetic adsorption of phenol onto peanut shell acid-activated carbon at different initial concentrations, carbon dosages and particle sizes has been developed. The adsorption kinetics were followed on the basis of the amount of phenol adsorbed at various time intervals at 22°C. The rate constant and the equilibrium adsorption capacity were calculated. From these parameters, empirical correlations for predicting the equilibrium adsorption capacity as a function of the C0/D ratio, and for estimating the rate constant as a function of the relation D/(C0dp)0.5, were derived. This allowed a general rate expression for design purposes to be obtained which was valid for C0/D ≤ 1.5. The operation line for each case studied was constructed and the equilibrium adsorption capacity obtained. A comparison was undertaken with the experimental adsorption isotherm as previously determined. The effect of the initial phenol concentration, the carbon dose and the particle size on the initial adsorption rate was also analyzed.

scholarly journals Effects of decreasing activated carbon particle diameter from 30 μm to 140 nm on equilibrium adsorption capacity

2017 ◽  
Vol 124 ◽  
pp. 425-434 ◽  
Author(s):  
Long Pan ◽  
Yuki Nishimura ◽  
Hideki Takaesu ◽  
Yoshihiko Matsui ◽  
Taku Matsushita ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Carbon Particle ◽  
Particle Diameter ◽  
Equilibrium Adsorption ◽  
Equilibrium Adsorption Capacity

scholarly journals Adsorption of Phenol from Aqueous Solution Using Activated Carbon prepared from Coconut Shell

2017 ◽  
Vol 29 (1) ◽  
pp. 9-13
Author(s):  
Masuma Sultana Ripa ◽  
Rafat Mahmood ◽  
Sabrina Khan ◽  
Easir A Khan
Keyword(s):  
Aqueous Solution ◽  
Activated Carbon ◽  
Adsorption Isotherm ◽  
Iodine Number ◽  
Chemical Engineering ◽  
Coconut Shell ◽  
Physical Activation ◽  
Batch Adsorption ◽  
Adsorption Model ◽  
Solution Ph

Adsorption separation of phenol from aqueous solution using activated carbon was investigated in this work. The adsorbent was prepared from coconut shell and activated by physical activation method. The coconut shell was first carbonized at 800°C under nitrogen atmosphere and activated by CO2 at the same temperature for one hour. The prepared activated carbon was characterized by Scanning Electron Microscope (SEM) and BET Surface Analyzer and by the determination of iodine number as well as Boehm titration. The iodine number indicates the degree of relative activation of the adsorbent. The equilibrium adsorption isotherm phenol from aqueous solution was performed using liquid phase batch adsorption experiments. The effect of experimental parameters including solution pH, agitation time, particle size, temperature and initial concentration was investigated. The equilibrium data was analyzed using Langmuir and Freundlich adsorption model to describe the adsorption isotherm and estimate the adsorption isotherm parameters. The results indicate the potential use of the adsorbent for removal of phenol from the aqueous solution.Journal of Chemical Engineering, Vol. 29, No. 1, 2017: 9-13

Nanoparticle Fe3O4 magnetized activated carbon from Armeniaca sibirica shell for the adsorption of Hg(II) ions

BioResources ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. 6100-6120
Author(s):  
Yinan Hao ◽  
Yanfei Pan ◽  
Qingwei Du ◽  
Xudong Li ◽  
Ximing Wang
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Ph Value ◽  
Removal Rate ◽  
Freundlich Isotherm ◽  
Entropy Change ◽  
Isotherm Models ◽  
Order Kinetic ◽  
Adsorption Parameters ◽  
Initial Concentration

Armeniaca sibirica shell activated carbon (ASSAC) magnetized by nanoparticle Fe3O4 prepared from Armeniaca sibirica shell was investigated to determine its adsorption for Hg2+ from wastewater. Fe3O4/ASSAC was characterized using XRD (X-ray diffraction), FTIR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), and BET (Brunauer–Emmett–Teller). Optimum adsorption parameters were determined based on the initial concentration of Hg2+, reaction time, reaction temperature, and pH value in adsorption studies. The experiment results demonstrated that the specific surface area of ASSAC decreased after magnetization; however the adsorption capacity and removal rate of Hg2+ increased 0.656 mg/g and 0.630%, respectively. When the initial concentration of Hg2+ solution was 250 mg/L and the pH value was 2, the adsorption time was 180 min and the temperature was 30 °C, and with the Fe3O4/ASSAC at 0.05 g, the adsorption reaching 97.1 mg/g, and the removal efficiency was 99.6%. The adsorption capacity of Fe3O4/ASSAC to Hg2+ was in accord with Freundlich isotherm models, and a pseudo-second-order kinetic equation was used to fit the adsorption best. The Gibbs free energy ΔGo < 0，enthalpy change ΔHo < 0, and entropy change ΔSo < 0 which manifested the adsorption was a spontaneous and exothermic process.

Adsorption of chromium (VI) from aqueous solutions on activated carbon

1994 ◽  
Vol 30 (9) ◽  
pp. 191-197 ◽  
Author(s):  
R. Leyva Ramos ◽  
A. Juarez Martinez ◽  
R. M. Guerrero Coronado
Keyword(s):  
Activated Carbon ◽  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Ph Effect ◽  
Freundlich Isotherm ◽  
Maximum Adsorption Capacity ◽  
Experimental Adsorption ◽  
Ph Values ◽  
Chromium Vi ◽  
Adsorption Data

The adsorption isotherm of chromium (VI) on activated carbon was obtained in a batch adsorber. The experimental adsorption data were fitted reasonably well to the Freundlich isotherm. The effect of pH on the adsorption isotherm was investigated at pH values of 4, 6, 7, 8, 10 and 12. It was found that at pH &lt; 6, Cr(VI) was adsorbed and reduced to Cr(III) by the catalytic action of the carbon and that at pH ≥ 12, Cr(VI) was not adsorbed on activated carbon. Maximum adsorption capacity was observed at pH 6 and the adsorption capacity was diminished about 17 times by increasing the pH from 6 to 10. The pH effect was attributed to the different complexes that Cr(VI) can form in aqueous solution. The adsorption isotherm was also affected by the temperature since the adsorption capacity was increased by raising the temperature from 25 to 40°C. It was concluded that Cr(VI) was adsorbed significantly on activated carbon at pH 6 and that the adsorption capacity was greatly dependent upon pH.

Adsorption Properties of Pr3+ and Nd3+ Using Silica Grafted with Larch Tannin

2012 ◽  
Vol 550-553 ◽  
pp. 1561-1565 ◽  
Author(s):  
Tian Tian Xu ◽  
Chu Rui Huang ◽  
Yuan Yuan Luo ◽  
Qiang Du ◽  
Shi Lin Zhao
Keyword(s):  
Adsorption Capacity ◽  
Ph Value ◽  
Adsorption Properties ◽  
Equilibrium Adsorption ◽  
Dynamics Model ◽  
Adsorption Capacities ◽  
Optimum Ph ◽  
Pseudo Second Order ◽  
Equilibrium Adsorption Capacity ◽  
Order Rate Equation

The new adsorption material was prepared by grafting the larch tannin onto aminated silica beads with the glutaraldehyde as the cross-linking agent. The adsorption properties of Pr3+and Nd3+on the new adsorbent material in aqueous solution were investigated. The results showed that the equilibrium adsorption capacities of this adsorbent to Pr3+, Nd3+were 402.12mg/g, 305.43mg/g at 303K when the initial concentrations of each ions were 442.7mg/L, 432.6mg/L, respectively and the pH value was 5.5; the maximum adsorption quantities of each ions were 576.34mg/g, 497.02mg/g at 303K when the initial concentrations of each ions were 704.5mg/L, 721.0mg/L, respectively and the pH value was 5.5. The effect of pH value was significant to the equilibrium adsorption capacity, the optimum pH values of this material to Pr3+and Nd3+were both 5.5; while the effect of the temperature was not obvious to the equilibrium adsorption capacity. The adsorption thermodynamics meet Freundlich equation, and the adsorption kinetics data of this adsorbent to Pr3+, Nd3+fitted with the pseudo-second-order rate equation dynamics model.

Adsorption of cadmium(II) from aqueous solution onto activated carbon

1997 ◽  
Vol 35 (7) ◽  
pp. 205-211 ◽  
Author(s):  
R. Leyva-Ramos ◽  
J. R. Rangel-Mendez ◽  
J. Mendoza-Barron ◽  
L. Fuentes-Rubio ◽  
R. M. Guerrero-Coronado
Keyword(s):  
Activated Carbon ◽  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Freundlich Isotherm ◽  
Carbon Surface ◽  
Maximum Adsorption Capacity ◽  
Solution Ph ◽  
Ph Values ◽  
Average Percent Deviation ◽  
Initial Ph

The adsorption isotherm of cadmium on activated carbon was measured in a batch adsorber. Effects of temperature and solution pH on the adsorption isotherm were investigated by determining the adsorption isotherm at temperatures of 10, 25, and 40°C and at initial pH values from 2 to 8. Langmuir isotherm better fitted the experimental data since the average percent deviation was lower than with the Freundlich isotherm It was noticed that the amount of Cd2+ adsorbed was reduced about 3 times by increasing the temperature from 10 to 40°C. It was found that Cd2+ was not adsorbed on activated carbon at pH of 2 or lower and that Cd2+ was precipitated out as Cd(OH)2 at pH values above 9. Maximum adsorption capacity was observed at pH of 8 and the adsorption capacity was decreased about 12 times by reducing the initial pH from 8 to 3. According to the cadmium speciation diagram the predominant species below pH of 8 is Cd2+. Thus, cadmium was adsorbed on the activated carbon surface as Cd2+. It was concluded that the adsorption capacity is a strong function of pH and temperature.

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