Reduction of azo dyes with zero-valent iron

Nam, Sangkil

doi:10.1016/s0043-1354(99)00331-0

Cited by 393 publications

(234 citation statements)

References 40 publications

Supporting

Mentioning

207

Contrasting

Unclassified

Order By: Relevance

“…Table 3 summarizes the first order rate constants obtained for monometallic systems. It can be seen that rate constants for Fe 0 (200 mg ml −1 ) mediated degradation of sunset yellow FCF dye and tartrazine dyes as reported by Nam and Tratnyek [18] are comparable to those obtained using 5 mg ml −1 Mg 0 alone in our investigations. The rate constant values are enhanced ∼four times if 20 mg ml −1 of Mg 0 is used.…”

Section: Comparison Of Dye Degradation Rate Constant Valuessupporting

confidence: 88%

“…The first order rate constants were calculated to be 0.074, 0.084 and 0.098 min −1 for 0.95, 1.4 and 1.9 mg ml −1 of Pd 0 , respectively. Nam and Tratnyek [18] studied the reduction of azo dyes in an anaerobic batch system using Fe 0 and reported that the dyes were reduced by first order kinetics. In our investigations the rate constant increases ∼1.2-1.3-fold for every 0.45 mg ml −1 increase in Pd 0 in the reaction mixture.…”

Section: Effect Of Varying Concentrations Of Pd 0 -Alumnia On the Kinmentioning

confidence: 99%

“…Thus the overall reaction is: [16][17][18][19][20][21][22][23][24][25][26][27]. Although Fe 0 has been applied extensively for remediation of several pollutants, the major drawbacks are slow reaction rates, rapid passivation of the metal and requirement for strict anaerobic conditions.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Decolourization of azo dyes using magnesium–palladium system

Patel¹,

Suresh²

2006

Journal of Hazardous Materials

117

View full text Add to dashboard Cite

Section: Comparison Of Dye Degradation Rate Constant Valuessupporting

confidence: 88%

Section: Effect Of Varying Concentrations Of Pd 0 -Alumnia On the Kinmentioning

confidence: 99%

See 1 more Smart Citation

Decolourization of azo dyes using magnesium–palladium system

Patel¹,

Suresh²

2006

Journal of Hazardous Materials

117

View full text Add to dashboard Cite

“…It should be noted that the efficacy of ZVI for the transformation of chlorinated hydrocarbons, azo dyes, and nitroaromatic compounds has been extensively investigated over the past 15 years (5)(6)(7)(8). ZVI exhibits a strong tendency to donate electrons in water:…”

mentioning

confidence: 99%

Enhanced Biological Treatment of Industrial Wastewater With Bimetallic Zero-Valent Iron

Zhang

2008

Environ. Sci. Technol.

181

View full text Add to dashboard Cite

In North America, zero-valent iron (ZVI) has been used in groundwater remediation for over a decade, by and large for the reduction of chlorinated organic compounds. Herein, we highlight recent experiments designed to integrate ZVI with biological processes for treatment of industrial process wastewater. A 60,000 m 3 /day (15.8 MGD) wastewater treatment plant featuring the integrated utilization of 910,000 kilograms (∼2.0 million pounds) of iron has been in successful operation since August 2006 in Shanghai, China.Municipal wastewater has traditionally been treated with biological processes, typically aerobic organisms in suspended systems (i.e., activated sludge) or surface-anchored biofilms. Industrial process wastes, on the other hand, are more challenging due to the presence of less biodegradable and often toxic pollutants (1, 2). To date, the ZVI process has not been used on a large scale in wastewater treatment, but demand for production of a higher quality treated effluent, including toxicity and nutrient reduction, has led to an intensive examination of some emerging technologies including the ZVI process.Over the past six years, we have studied the use of iron shavings, especially turnings or shavings of 38CrMoAl steel ( Figure 1) for enhanced biological treatment of industrial process wastewater. The iron shavings contain iron (>95%), carbon(0.35-0.42%), silica(0.2-0.45%), chromium(1.35-1.65%), and a few other trace elements (e.g., Mo, S, P, Ni, each <0.03%). The primary reason for this selection is the abundant local supply and relatively low cost (∼$0.25/kg). The iron shavings have a fairly large surface area (∼0.2-0.3 m 2 /kg) and feature excellent mechanical and hydraulic characteristics (e.g., high porosity) as a filter medium.Since 2001, the National Engineering Research Center for Urban Pollution Control at Tongji University has undertaken a major research and development project to investigate the technical and economic feasibility of iron shavings for the enhanced treatment of industrial process wastes. We have examined the reactivity of iron shavings as a substitute for conventional iron powders in the transformation of a wide variety of recalcitrant organic pollutants. Particularly, the reactions of iron shavings with three groups of organic pollutantsschlorinated aliphatic compounds, organic dyes, and nitroaromatic compoundsshave been investigated. Those compounds are pollutants commonly found in wastes from petrochemical, textile, and pharmaceutical industries. A series of pilot-and full-scale experiments has been completed to advance the ZVI reactor design, fabrication, operation, and maintenance. The effect of ZVI pretreatment on microbial growth and biodegradation has been the theme of several recent dissertations. Ongoing research also includes the investigation of ZVI for treatment of emerging persistent organic compounds such as polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs).Reactions of Iron Shavings with Chlorinated Aliphatic Compounds Batch experiments ...

show abstract

“…Zerovalent iron (ZVI) has been used as a reducing agent to remediate many organic compounds such as halogenated aliphatics (Gillham and Ohannesin, 1994), azo dyes (Nam and Tratnyek, 2000), nitrobenzene (Mu et al, 2004), nitroaromatic pesticides (Keum and Li, 2004) as well as RDX (Oh et al, 2005a). While those studies mainly focused on RDX removal from water, in situ soil remediation applications mainly involve RDX from a solid phase.…”

Section: Introductionmentioning

confidence: 99%

Dynamic and equilibrium studies of the RDX removal from soil using CMC-coated zerovalent iron nanoparticles

Naja

Apiratikul

Pavasant

et al. 2009

Environmental Pollution

View full text Add to dashboard Cite

RDX chemical degradation in a contaminated soil was conducted using coated zerovalent iron nanoparticles in both batchRapid chemical degradation of toxic RDX explosive in soil can be accomplished using zerovalent nanoiron suspension stabilized in dilute carboxymethyl cellulose solution (CMC-ZVINs). The effect of operating conditions (redox-potential, Fe/RDX molar ratio) was studied on batchwise removal of RDX in contaminated soil. While anaerobic conditions resulted in 98% RDX removal in 3 h, only slightly over 60% RDX removal could be attained under aerobic conditions. The molar ratio did not have any influence on the intermediate and final RDX degradation products (methylenedinitramine, nitroso derivative, N 2 ,N 2 O, NO 2 À ), however, their distribution changed. Dynamic studies were conducted using a flow-through short column packed with RDX-contaminated soil and fed with CMC-ZVINs. The column was operated at two interstitial velocities (2.2 and 1.6 cm min À1 ), resulting in the 76.6% and 95% removal of the initial RDX soil contamination load (60 mg kg À1 ), respectively. While the column operating conditions could be further optimized, 95% of the RDX initially present in the contaminated soil packed in the column was degraded when flushed with a CMC-ZVINs suspension in this work.

show abstract

Reduction of azo dyes with zero-valent iron

Cited by 393 publications

References 40 publications

Decolourization of azo dyes using magnesium–palladium system

Decolourization of azo dyes using magnesium–palladium system

Enhanced Biological Treatment of Industrial Wastewater With Bimetallic Zero-Valent Iron

Dynamic and equilibrium studies of the RDX removal from soil using CMC-coated zerovalent iron nanoparticles

Contact Info

Product

Resources

About