Hexavalent Chromium (VI) Removal by Aspergillus niger

Author(s):  
Ismael Acosta-Rodriguez ◽  
Juan F. Cardenas-González ◽  
María de Guadalupe Moctezuma-Zárate ◽  
Adriana Rodriguez Perez ◽  
Victor M. Martínez-Juárez
2009 ◽  
Vol 9 (6) ◽  
pp. 661-670 ◽  
Author(s):  
S. P. Dubey ◽  
K. Gopal

The activated carbon of Eucalyptus globulus was tested for their effectiveness in removing hexavalent chromium from aqueous solution using column experiments. Result revealed that adsorption of chromium(VI) on eucalyptus bark carbon was endothermic in nature. Thermodynamic parameters such as the entropy change, enthalpy change and Gibbs free energy change were found to be 1.39 kJ mol−1 K−1, 1.08 kJ mol−1 and −3.85 kJ mol−1, respectively. Different chromium concentrations were used for the fixed bed adsorption studies. The pre- and post-treated adsorbents were characterized using a FTIR spectroscopic technique. It was concluded that Eucalyptus bark carbon column could be used effectively for removal of hexavalent chromium from aqueous solution at optimal column conditions. This study showed that this biological material is potential adsorbent of Cr(VI) from water.


2020 ◽  
Vol 38 (1) ◽  
pp. 20-28 ◽  
Author(s):  
Hui Xu ◽  
Rui-xia Hao ◽  
Xi-yang Xu ◽  
Yang Ding ◽  
An-huai Lu ◽  
...  

2016 ◽  
Vol 721 ◽  
pp. 143-148 ◽  
Author(s):  
Nora Noureddine ◽  
Samia Benhammadi ◽  
Fouad Kara ◽  
Hakim Aguedal ◽  
Abdelkader Iddou ◽  
...  

A bacterial strain Pseudomonas aeruginosa isolated from an uncontaminated soil has been used for the removal of hexavalent chromium (Cr (VI)). The experiments were carried out in batch system in a culture broth. The results obtained have shown that 100% of Cr (VI) are removed. Contact time, initial concentration of the hexavalent chromium, temperature, as well as the nature of the culture broth have influenced this elimination. To the initial concentration of 20g/L of Cr (VI) the elimination rates are lower, while the reverse occurs for an initial concentration of 8g/L. This study allows considering the use of Pseudomonas aeruginosa in the treatment of water polluted by toxic heavy metals such as Cr (VI).


2012 ◽  
Vol 430-432 ◽  
pp. 1253-1256 ◽  
Author(s):  
Yu Jie Huang ◽  
Huan Zhen Zhang

In order to improve the removal ability of hexavalent chromium on the synthetic zeolite, the synthetic zeolite was modified by FeSO4, which was used to removal hexavalent chromium in groundwater. The results showed that the concentration of Cr (VI) can be reduced from 5.0mg/l to 0.03 mg/l, which meets the requirements of groundwater standards (0.05mg/l) by using modified zeolite in a liquid-to-solid ratio of 20 ml/g, pH=3 for 120 minutes. The adsorption of Cr (VI) on the modified synthetic zeolite could be described by the Langmuir and Freundlich adsorption isotherm. It is showed that the synthetic zeolite modified by FeSO4 has good treatment effect and after treatment the pH of groundwater can reach around 6.8, which need no more pH adjustment.


Author(s):  
Soumyajit Guha ◽  
Sampa Debnath ◽  
Saswati Gayen

The main objective of this study was to isolate, characterize, and determine chromium (VI) tolerance capacities of fungal strains from tannery effluent of the Kolkata Leather Complex area. Chromium (VI) is a heavy metal that is known to be toxic as well as carcinogenic. It is an important heavy metal widely used in various industries of which the tanning industry deserves special mention. The majority of Cr (VI) waste is discharged into the environment annually as a consequence of industrial and manufacturing activities. Kolkata Leather Complex is an industrial complex intended to serve as a central leather-tanning complex for Kolkata located at Bantala, near East Kolkata, India. Samples (tannery effluent) were collected in sterile capped tubes from Kolkata Leather Complex Area and brought to the laboratory for analysis. The samples were serially diluted and were plated on Czapekdox agar plates and incubated at 300C. After a few days, a number of morphologically different colonies were selected and sequentially subcultured for pure colony isolation on the same medium. They were preserved in the refrigerator at 40 C. Lactophenol cotton blue staining was done to observe and record the fungal morphological characteristics. They were further assessed for their hexavalent chromium tolerance capacities and subsequently the metal tolerance index was derived for each strain respectively. All 16 fungal strains isolated from the Kolkata Leather Complex tannery area were found to be chromium (VI) tolerant starting at 0.1mg/ml Cr (VI) concentration. Maximum chromium (VI) tolerance was displayed by sample S12 (2mg/ml) which was later identified as having 99.82% similarity with Aspergillus nomius strain.Keywords: effluent, fungi, heavy metal, isolation, hexavalent chromium, tannery, tolerance.


2021 ◽  
Vol 16 (2) ◽  
pp. 436-451
Author(s):  
Meghdad Sheikhi ◽  
Hassan Rezaei

Abstract Treatment of the industrial wastewater before discharging into aquatic ecosystems using a new technology such as nanotechnology seems necessary. There are different methods for the removal of the heavy metals in the wastewater. In this study, nano-chitin was purchased from the Nano-Novin Polymer Company and used as an adsorbent for the removal of chromium (VI) ions from aqueous solution in a batch system. The effects of pH, temperature, contact time, concentration, and adsorbent dose were investigated. According to the results, the optimum conditions of adsorption occurred at pH = 6, temperature = 25 °C, 60 minutes contact time, and 0.6 g·L−1 adsorbent dose. Investigation of equilibrium isotherms showed that the isotherm fitted the Freundlich model with a correlation coefficient of R2 = 0.9689. The pseudo second-order model with the larger correlation coefficient had a greater fitness against experimental data in the kinetic studies. Thermodynamic parameters such as Gibbs free energy, enthalpy, and entropy were calculated, which indicated spontaneous, endothermic, and random processes, respectively. Given the good results of this project, nano-chitin can be suggested as a novel adsorbent which is highly capable of adsorbing hexavalent chromium from aqueous solutions.


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