TY - JOUR
T1 - Effect of pH on hexavalent and total chromium removal from aqueous solutions by avocado shell using batch and continuous systems
AU - Aranda-García, Erick
AU - Cristiani-Urbina, Eliseo
N1 - Publisher Copyright:
© 2017, Springer-Verlag GmbH Germany.
PY - 2019/2/8
Y1 - 2019/2/8
N2 - Solution pH appears to be the most important regulator of the biosorptive removal of chromium ions from aqueous solutions. This work presents a kinetic study of the effects of solution pH on Cr(VI) and total chromium removal from aqueous solution by Hass avocado shell (HAS) in batch and continuous packed bed column systems. Different Cr(VI) and total chromium removal performances of HAS were obtained in pH-shift batch, pH-controlled batch, and continuous systems. These results emphasize the great importance of determining the most appropriate pH for Cr(VI) and total chromium removal, considering the operational mode of the proposed large-scale treatment system. Total chromium biosorption batch kinetics was well described by the Elovich model, whereas in the continuous system, the fitness of the kinetic models to the experimental data was pH dependent. X-ray photoelectron spectroscopy and kinetic studies clearly indicated that the reaction mechanism of Cr(VI) with HAS was the reductive biotransformation of Cr(VI) to Cr(III), which was partially released to the aqueous solution and partially biosorbed onto HAS.
AB - Solution pH appears to be the most important regulator of the biosorptive removal of chromium ions from aqueous solutions. This work presents a kinetic study of the effects of solution pH on Cr(VI) and total chromium removal from aqueous solution by Hass avocado shell (HAS) in batch and continuous packed bed column systems. Different Cr(VI) and total chromium removal performances of HAS were obtained in pH-shift batch, pH-controlled batch, and continuous systems. These results emphasize the great importance of determining the most appropriate pH for Cr(VI) and total chromium removal, considering the operational mode of the proposed large-scale treatment system. Total chromium biosorption batch kinetics was well described by the Elovich model, whereas in the continuous system, the fitness of the kinetic models to the experimental data was pH dependent. X-ray photoelectron spectroscopy and kinetic studies clearly indicated that the reaction mechanism of Cr(VI) with HAS was the reductive biotransformation of Cr(VI) to Cr(III), which was partially released to the aqueous solution and partially biosorbed onto HAS.
KW - Avocado shell
KW - Biosorption
KW - Hexavalent chromium
KW - Total chromium
KW - Wastewater treatment
KW - pH
UR - http://www.scopus.com/inward/record.url?scp=85030183493&partnerID=8YFLogxK
U2 - 10.1007/s11356-017-0248-z
DO - 10.1007/s11356-017-0248-z
M3 - Artículo
C2 - 28963647
SN - 0944-1344
VL - 26
SP - 3157
EP - 3173
JO - Environmental Science and Pollution Research
JF - Environmental Science and Pollution Research
IS - 4
ER -