Limits...
Arsenic (III) adsorption on iron acetate coated activated alumina: thermodynamic, kinetics and equilibrium approach.

Das B, Devi RR, Umlong IM, Borah K, Banerjee S, Talukdar AK - J Environ Health Sci Eng (2013)

Bottom Line: The sorption was reasonably explained with Langmuir and Freundlich isotherms.The thermodynamic parameters such as ΔG0, ΔH0, ΔS0 and Ea were calculated in order to understand the nature of sorption process.The sorption process was found to be controlled by pseudo-second order and intraparticle diffusion models.

View Article: PubMed Central - HTML - PubMed

Affiliation: Defence Research Laboratory (DRDO), Tezpur, India. das_drlt@rediffmail.com.

ABSTRACT
The adsorption potential of iron acetate coated activated alumina (IACAA) for removal of arsenic [As (III)] as arsenite by batch sorption technique is described. IACAA was characterized by XRD, FTIR, EDAX and SEM instruments. Percentage adsorption on IACAA was determined as a function of pH, contact time and adsorbent dose. The study revealed that the removal of As (III) was best achieved at pH =7.4. The initial As (III) concentration (0.45 mg/L) came down to less than 0.01 mg/L at contact time 90 min with adsorbent dose of 1 g/100 mL. The sorption was reasonably explained with Langmuir and Freundlich isotherms. The thermodynamic parameters such as ΔG0, ΔH0, ΔS0 and Ea were calculated in order to understand the nature of sorption process. The sorption process was found to be controlled by pseudo-second order and intraparticle diffusion models.

No MeSH data available.


Effect of pH on As (III) adsorption at As(III)concentration = 0.45 mg/L, adsorbentdose = 1 g/100 ml and contacttime = 90 min.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4109662&req=5

Figure 2: Effect of pH on As (III) adsorption at As(III)concentration = 0.45 mg/L, adsorbentdose = 1 g/100 ml and contacttime = 90 min.

Mentions: The effect of pH on the adsorption of As (III) onto IACAA was studied in the pHrange of 4.2 to 9.2. Figure 2 reveals that theefficiency of As (III) removal increases with increasing pH from 4.2 to 7.4. Inthe present study best arsenic removal of 98.5% has been achieved atpH = 7.4. The removal efficiency of IACAA is found to decrease bothat lower and higher pH from 7.4. The highly protonated surface of IACAA is notfavourable for As (III) removal resulting almost no change in the extent ofadsorption within the pH range 4.2 to 6.1. With increase in pH of the system,the degree of protonation of the surface reduces gradually and approaches tozero near zero point charge (ZPC) of the adsorbent. The species likeH2AsO4 - andHAsO4 2- which may be formed during theadsorption process may play a role in the molecule surface interaction orocclusion phenomena and may also affect the arsenic adsorption mechanism [31].


Arsenic (III) adsorption on iron acetate coated activated alumina: thermodynamic, kinetics and equilibrium approach.

Das B, Devi RR, Umlong IM, Borah K, Banerjee S, Talukdar AK - J Environ Health Sci Eng (2013)

Effect of pH on As (III) adsorption at As(III)concentration = 0.45 mg/L, adsorbentdose = 1 g/100 ml and contacttime = 90 min.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4109662&req=5

Figure 2: Effect of pH on As (III) adsorption at As(III)concentration = 0.45 mg/L, adsorbentdose = 1 g/100 ml and contacttime = 90 min.
Mentions: The effect of pH on the adsorption of As (III) onto IACAA was studied in the pHrange of 4.2 to 9.2. Figure 2 reveals that theefficiency of As (III) removal increases with increasing pH from 4.2 to 7.4. Inthe present study best arsenic removal of 98.5% has been achieved atpH = 7.4. The removal efficiency of IACAA is found to decrease bothat lower and higher pH from 7.4. The highly protonated surface of IACAA is notfavourable for As (III) removal resulting almost no change in the extent ofadsorption within the pH range 4.2 to 6.1. With increase in pH of the system,the degree of protonation of the surface reduces gradually and approaches tozero near zero point charge (ZPC) of the adsorbent. The species likeH2AsO4 - andHAsO4 2- which may be formed during theadsorption process may play a role in the molecule surface interaction orocclusion phenomena and may also affect the arsenic adsorption mechanism [31].

Bottom Line: The sorption was reasonably explained with Langmuir and Freundlich isotherms.The thermodynamic parameters such as ΔG0, ΔH0, ΔS0 and Ea were calculated in order to understand the nature of sorption process.The sorption process was found to be controlled by pseudo-second order and intraparticle diffusion models.

View Article: PubMed Central - HTML - PubMed

Affiliation: Defence Research Laboratory (DRDO), Tezpur, India. das_drlt@rediffmail.com.

ABSTRACT
The adsorption potential of iron acetate coated activated alumina (IACAA) for removal of arsenic [As (III)] as arsenite by batch sorption technique is described. IACAA was characterized by XRD, FTIR, EDAX and SEM instruments. Percentage adsorption on IACAA was determined as a function of pH, contact time and adsorbent dose. The study revealed that the removal of As (III) was best achieved at pH =7.4. The initial As (III) concentration (0.45 mg/L) came down to less than 0.01 mg/L at contact time 90 min with adsorbent dose of 1 g/100 mL. The sorption was reasonably explained with Langmuir and Freundlich isotherms. The thermodynamic parameters such as ΔG0, ΔH0, ΔS0 and Ea were calculated in order to understand the nature of sorption process. The sorption process was found to be controlled by pseudo-second order and intraparticle diffusion models.

No MeSH data available.