TOTAL CHROMIUM AND HEXAVALENT CHROMIUM IN AIR FROM SOLID TANNERY WASTES AND HEALTH RISKS FOR SLUM POPULATION IN BANGLADESH

2016 ◽  
Author(s):  
Mohammad Alauddin ◽  
◽  
Rabije Cekovic ◽  
Sarah Alauddin ◽  
Sandra Minchala ◽  
...  
Keyword(s):  
Hexavalent Chromium ◽  
Health Risks ◽  
Total Chromium ◽  
Tannery Wastes ◽  
Slum Population

Total chromium and hexavalent chromium occurrence analysis

2013 ◽  
Vol 105 (6) ◽  
pp. E310-E319 ◽  
Author(s):  
Chad J. Seidel ◽  
Christopher J. Corwin
Keyword(s):  
Hexavalent Chromium ◽  
Total Chromium

Interference of Sb(III) in the Determination of Hexavalent Chromium in Thermoplastic Matrices

2011 ◽  
Vol 2011 (1) ◽  
pp. 000345-000351
Author(s):  
Sophia S. Lau ◽  
Joe P. Kuczynski
Keyword(s):  
Hexavalent Chromium ◽  
Flame Retardants ◽  
Test Method ◽  
Polymer Matrices ◽  
Antimony Trioxide ◽  
False Negatives ◽  
Total Chromium ◽  
Adverse Health Effects ◽  
The Eu

Due to the adverse health effects of hexavalent chromium, Cr(VI), pigments and other materials containing Cr(VI) were largely banned for use in electrotechnical products under the EU RoHS Directive [1]. While there are several effective methods to determine the presence of total chromium in electrotechnical plastic matrices, a validated compliance test method that is capable of discerning Cr(VI) from the non-regulated forms of Cr(III) is not yet available. One of the challenges in developing a standardized compliance test for Cr(VI) is the low recovery of Cr(VI) compounds from polymer matrices This study identified antimony trioxide (ATO), a common synergist added to enhance the ignition resistance of brominated flame retardants (BFRs), as a source of matrix interference in the quantitative determination of hexavalent chromium extracted from polymer matrices. ATO reduces hexavalent chromium to trivalent chromium prior to complexation of Cr(VI) with diphenylcarbazide (DPC) leading to false negatives. EDTA was found to be an efficient reagent for Sb(III) complexation, thereby suppressing the reduction of Cr(VI) and enabling quantitative Cr(VI) determination in the presence of ATO.

Optimization for Reduction/Precipitation Treatment of Hexavalent Chromium

1994 ◽  
Vol 29 (9) ◽  
pp. 275-284 ◽  
Author(s):  
J. W. Patterson ◽  
E. Gasca ◽  
Y. Wang
Keyword(s):  
Wastewater Treatment ◽  
Hexavalent Chromium ◽  
Treatment Plant ◽  
Kinetic Studies ◽  
Critical Parameters ◽  
Sodium Metabisulfite ◽  
Treatment Optimization ◽  
Total Chromium ◽  
Manufacturing Operations ◽  
Treatment Train

This paper describes wastewater treatment optimization studies performed on an industrial wastewater generated in Boston, Massachusetts, USA. The manufacturing plant generates hexavalent chromium [Cr(VI)] wastewater as a result of chromating brass, bronze and copper parts produced in the manufacturing operations. The facility utilizes a continuous flow treatment train, involving segregated Cr(VI) reduction with sodium metabisulfite (Na2S2O5) under acidic conditions, followed by combined wastestream two-stage pH adjustment, metals precipitation, and clarification before discharge to the municipal sewer. The objectives of the studies were to define and evaluate critical parameters, such as pH and oxidation reduction potential (ORP) for hexavalent and total chromium control and to perform treatability studies to optimize the performance of the wastewater treatment plant (WWTP). The treatability studies included Cr(VI) reduction versus Na2S2O5 dosage evaluations and corresponding chromium reduction kinetic studies, and trivalent chromium hydroxide precipitation. The Cr(VI) reduction experiments and chromic hydroxide precipitation studies were performed for three different wastewaters collected from within the manufacturing process; a high, typical, and dilute strength wastewater.

Soil Contamination From Tannery Wastes with Emphasis on the Fate and Distribution of Tri- and Hexavalent Chromium

2008 ◽  
Vol 199 (1-4) ◽  
pp. 123-137 ◽  
Author(s):  
Khaled Mahmud Shams ◽  
Gottfried Tichy ◽  
Manfred Sager ◽  
Thomas Peer ◽  
Ashtar Bashar ◽  
...  
Keyword(s):  
Soil Contamination ◽  
Hexavalent Chromium ◽  
Tannery Wastes

scholarly journals Appraisal of Chromium Contents from Different Tanneries and Drains of Sialkot

2020 ◽  
Vol 63 (2) ◽  
pp. 112-117
Author(s):  
Amin Riaz ◽  
Abid Zia
Keyword(s):  
Hexavalent Chromium ◽  
Oxygen Demand ◽  
Absorption Spectrometry ◽  
Total Dissolved Solids ◽  
Biological Oxygen Demand ◽  
Pollution Level ◽  
Total Chromium ◽  
Industrial City ◽  
Uv Visible ◽  
Tanning Industry

The tanning industry is the major chromium consuming industry. Tanning industries are present throughout Pakistan, but their presence is more concentrated in small industrial city Sialkot. The samples of wastewater were collected from different tanneries and Nullah Aik which are situated in Sialkot and analyzed for the measurement of pollution level. The effluents sample demonstrated high values of temperature (32-42°C), pH (5.1-10.9), biological oxygen demand (335-5818 mg/L), chemical oxygen demand (740-14546 mg/L), total solids (2265-19314 mg/L), total dissolved solids (1313-17467 mg/L), hexavalent chromium (1.8-9.8 mg/L), and total chromium (3.75-16.7 mg/L). The total chromium analyzed by atomic absorption spectrometry and hexavalent chromium determined by UV-Visible Spectrophotometer with DCP. The study focused on the level of pollution in tannery wastewater to estimate the impairment caused by them.    

Transference of total chromium and hexavalent chromium from soils to mushrooms

2007 ◽  
Vol 172 ◽  
pp. S193
Author(s):  
Estela Figueiredo ◽  
Maria Elisa Soares ◽  
Marisa Castro ◽  
Maria de Lourdes Bastos
Keyword(s):  
Hexavalent Chromium ◽  
Total Chromium

Hexavalent chromium removal in vitro and from industrial wastes, using chromate-resistant strains of filamentous fungi indigenous to contaminated wastes

2006 ◽  
Vol 52 (9) ◽  
pp. 809-815 ◽  
Author(s):  
Francisco Javier Acevedo-Aguilar ◽  
Angeles Edith Espino-Saldaña ◽  
Ireri Lizzuli Leon-Rodriguez ◽  
Ma. Elena Rivera-Cano ◽  
Mario Avila-Rodriguez ◽  
...  
Keyword(s):  
Filamentous Fungi ◽  
Hexavalent Chromium ◽  
Growth Medium ◽  
Reduction Process ◽  
Industrial Wastes ◽  
Complete Disappearance ◽  
Total Chromium ◽  
Penicillium Sp ◽  
Aspergillus Sp

Two chromate-resistant filamentous fungi, strains H13 and Ed8, were selected from seven independent fungal isolates indigenous to Cr(VI)-contaminated soil because of their ability to decrease hexavalent chromium levels in the growth medium. Morphophysiological studies identified strain H13 as a Penicillium sp. isolate and Ed8 as an Aspergillus sp. isolate. When incubated in minimal medium with glucose as a carbon source and in the presence of 50 µg/mL Cr(VI), these strains caused complete disappearance of Cr(VI) in the growth medium after about 72 h of incubation. Total chromium concentration in growth medium was constant during culture growth, and no accumulation of chromium in fungal biomass was observed. Quantitative determinations of oxidized and reduced chromium species during the reduction process revealed stoichiometric conversion of Cr(VI) to Cr(III). A decrease in Cr(VI) levels from industrial wastes was also induced by Ed8 or H13 biomass. These results indicate that chromate-resistant filamentous fungi with Cr(VI)-reducing capability could be useful for the removal of Cr(VI) contamination.Key words: Cr(VI) reduction, Cr(VI) resistance, filamentous fungi, Aspergillus sp., Penicillium sp., industrial wastes.

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