Coconut coir as biosorbent for Cr(VI) removal from laboratory wastewater

Gonzalez, Mário H.; Labuto, Geórgia; Pelizaro, Claudia B.; Menezes, E. A.; Lemos, Sherlan G.; Sousa, Gilberto Batista de; Nogueira, Ana Rita A.

doi:10.1016/j.jhazmat.2008.02.014

Cited by 90 publications

(38 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Only few Fig. 8 (Sharma and Forster 1994;Dakiky et al 2002;Gonzalez et al 2008;Anandkumar and Mandal 2009;Bansal et al 2009;Dhir and Kumar 2010;Rao and Rehman 2010;Blanes et al 2016). It may be seen in the figure that adsorption capacity of these biomass-based low-cost adsorbents varies in the range of 5-80 mg/g for adsorption experiments carried out at 298-303 K. Teff straw has better adsorption capacity than most of the adsorbents; however, a few have better adsorption capacity than teff straw as well.…”

Section: Adsorption Mechanism and Comparative Assessmentmentioning

confidence: 96%

Chemical treatment of teff straw by sodium hydroxide, phosphoric acid and zinc chloride: adsorptive removal of chromium

Wassie

Srivastava

2016

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

In this study, teff (Eragrostis tef) straw has been chemically treated and tested as an adsorbent for Cr(VI) removal. Chemically treatment of teff straw was done by NaOH, H 3 PO 4 and ZnCl 2 solutions. Scanning electron micrograph and X-ray diffraction were used for anatomical characterization, whereas Fourier transform infrared spectroscopy was used for surface change characterization of adsorbents. Effects of different experimental parameters like pH (2-12), initial Cr(VI) concentration (100-900 mg/L), adsorbent dose (2.5-20 g/L), contact time (15-360 min) and temperature (288-318 K) were studied. Temperature increment was found to stimulate the adsorption process. Langmuir isotherm was found to give better representation over wide range of temperature for untreated, H 3 PO 4 -as well as ZnCl 2 -treated teff straw, and Freundlich isotherm best represented the isotherm data for NaOH-treated teff straw. Maximum Cr(VI) adsorption capacity of untreated, NaOH-, H 3 PO 4 -and ZnCl 2 -treated teff straw was found to be 86.1, 73.8, 89.3 and 88.9 mg/g, respectively. Respective values of average effective diffusion coefficient (D e ) were found to be 2.8 9 10 -13 , 2.59 9 10 -14 , 1.32 9 10 -13 and 1.14 9 10 -13 m 2 /s, respectively. The negative value of DG o for all the adsorbents indicates Cr(VI) spontaneous adsorption. Isosteric heat of adsorption (DH st,a ) was found to vary with surface coverage (h). DH st,a increased for untreated, H 3 PO 4 -and ZnCl 2 -treated teff straw, and decreased steadily with h for NaOH-treated teff straw.

show abstract

Section: Adsorption Mechanism and Comparative Assessmentmentioning

confidence: 96%

Chemical treatment of teff straw by sodium hydroxide, phosphoric acid and zinc chloride: adsorptive removal of chromium

Wassie

Srivastava

2016

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…In the present study raw coconut coir was modified by sodium chlorite to enhance the adsorption capacity which was not good enough in the previous study for the removal of Cr(VI) by this sort of bioadsorbent (Gonzalez et al, 2008). Besides, the effect of pH on the adsorption kinetics of Cr(VI) on SCT-CC was also investigated.…”

Section: Introductionmentioning

confidence: 83%

“…The process was found to be exothermic with a maximum adsorption of 91.0% at 30ºC for an initial concentration of 100 mg/L at pH 3.00. Coconut coir was also used as bioadsorbent in order to remove Cr(VI) from laboratory waste water (Gonzalez et al, 2008). The research revealed that about 17% of chromium had been removed from sulphochromic waste water solution by dried coconut coir whereas 72% of chromium was removed by hydrated coconut coir.…”

Section: Introductionmentioning

confidence: 99%

Effect of pH on the adsorption kinetics of Cr(VI) on sodium chlorite treated coconut coir

Islam¹,

Ahmed²,

Hossain³

et al. 2016

Bangladesh J. Sci. Ind. Res.

View full text Add to dashboard Cite

Coconut coir is a low cost bioadsorbent containing large amount of lignin. In this research work sodium chlorite treated coconut coir (SCT-CC) was used to remove Cr(VI) from industrial wastewater by implementing adsorption technique through the investigation of the adsorption kinetics at different pH values. The maximum Cr(VI) adsorption capacity of SCT-CC at pH 2.00, 3.00, 5.00 and 7.00 was 24.75, 23.92, 16.07 and 6.31 mg Cr(VI) g -1 SCT-CC respectively with the dose of 7.5 g/L. The equilibrium established within three hours resulting the maximum removal (95%) of chromium. The adsorption kinetics of Cr(VI) on SCT-CC was found to be regulated by pH of the system. Rate of adsorption was the highest at pH 2.00 and the kinetic data well-fitted with Ho's pseudo second order kinetics. Fourier transform infrared (FT-IR) spectrometry analysis indicated that the carbonyl (C=O) groups and hydroxy (O-H) groups from the lignin structure in coconut coir may be involved in the mechanism of Cr(VI) adsorption and it showed good agreement with the kinetic data to elucidate the adsorption mechanism.

show abstract

“…Stretching of bonds in 650-400/cm is due to F-O bond vibration in which SO 2 and NO 2 has escaped out. It is inferred from the spectrum that the adsorbent contain hydrocarbon with hydroxyl groups (Gonzalez et al 2008;Nadeem et al 2009;Mungapati et al 2009;Meenakshi sundaram et al 2011).…”

Section: Ftir Analysismentioning

confidence: 99%

Fluoride removal study using pyrolyzed Delonix regia pod, an unconventional adsorbent

Ajisha¹,

Rajagopal²

2014

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

Applicability of the new material pyrolyzed Delonix regia pod carbon for the removal of excess fluoride ions from the water that harm the human and the environment was studied. The adsorbent was characterized both physically and chemically. Surface chemistry characterization was done with pH-drift method. Batch adsorption studies were carried out for the effect of pH, dosage, contact time, initial fluoride concentration, temperature and interfering co-ions. The physicochemical properties and textural characters were analyzed. Equilibrium data were studied using Freundlich, Langmuir, Temkin and Dubinin-Radushkevich models, in which Freundlich isotherm was considered to be the best fit for the adsorbent. The sorption nature was studied using thermodynamic parameters which showed spontaneous, irreversible, stable and endothermic. The adsorption kinetics follows pseudo-second order. The mechanism of adsorption was determined from intraparticle diffusion model. Boyd plot showed that the adsorption of fluoride on the carbon was mainly governed by particle diffusion.

show abstract

Coconut coir as biosorbent for Cr(VI) removal from laboratory wastewater

Cited by 90 publications

References 26 publications

Chemical treatment of teff straw by sodium hydroxide, phosphoric acid and zinc chloride: adsorptive removal of chromium

Chemical treatment of teff straw by sodium hydroxide, phosphoric acid and zinc chloride: adsorptive removal of chromium

Effect of pH on the adsorption kinetics of Cr(VI) on sodium chlorite treated coconut coir

Fluoride removal study using pyrolyzed Delonix regia pod, an unconventional adsorbent

Contact Info

Product

Resources

About