As the environment preservation gradually becomes a matter of major social concern and more strict legislation is being imposed on effluent discharge, more effective processes are required to deal with non-readily biodegradable and toxic pollutants. Synthetic organic dyes in industrial effluents cannot be destroyed in conventional wastewater treatment and consequently, an urgent challenge is the development of new environmentally benign technologies able to mineralize completely these non-biodegradable compounds. This review aims to increase the knowledge on the electrochemical methods used at lab and pilot plant scale to decontaminate synthetic and real effluents containing dyes, considering the period from 2009 to 2013, as an update of our previous review up to 2008. Fundamentals and main applications of electrochemical advanced oxidation processes and the other electrochemical approaches are described. Typical methods such as electrocoagulation, electrochemical reduction, electrochemical oxidation and indirect electro-oxidation with active chlorine species are discussed. Recent advances on electrocatalysis related to the nature of anode material to generate strong heterogeneous OH as mediated oxidant of dyes in electrochemical oxidation are extensively examined. The fast destruction of dyestuffs mediated with electrogenerated active chlorine is analyzed. Electro-Fenton and photo-assisted electrochemical methods like photoelectrocatalysis and photoelectro-Fenton, which destroy dyes by heterogeneous OH and/or homogeneous OH produced in the solution bulk, are described. Current advantages of the exposition of effluents to sunlight in the emerging photo-assisted procedures of solar photoelectrocatalysis and solar photoelectro-Fenton are detailed. The characteristics of novel combined methods involving photocatalysis, adsorption, nanofiltration, microwaves and ultrasounds among others and the use of microbial fuel cells are finally discussed.

Decontamination of wastewaters containing synthetic organic dyes by electrochemical methods. An updated review

2.2. Fenton’s Chemistry 6575 2.2.1. Origins 6575 2.2.2. Fenton Process 6575 2.3. Photo-Fenton Process 6577 3. H2O2 Electrogeneration for Water Treatment 6577 3.1. Fundamentals 6578 3.2. Cathode Materials 6579 3.3. Divided Cells 6580 3.4. Undivided Cells 6583 4. Electro-Fenton (EF) Process 6585 4.1. Origins 6585 4.2. Fundamentals of EF for Water Remediation 6586 4.2.1. Cell Configuration 6586 4.2.2. Cathodic Fe2+ Regeneration 6586 4.2.3. Anodic Generation of Heterogeneous Hydroxyl Radical 6587

Electro-Fenton process and related electrochemical technologies based on Fenton's reaction chemistry

Adsorption of methylene blue on low-cost adsorbents: A review

The science of the total environment

Fouling in membrane bioreactors used in wastewater treatment

Modified graphite electrode by polyaniline/tourmaline improves the performance of bio-cathode microbial fuel cell

In the present study accelerated solvent extraction (ASE) was investigated for the extraction of organochlorine pesticides from animal feed. The factors influencing the extraction efficiency including extraction temperature, static extraction time and composition of extraction solvent were optimized using response surface methods. Clean-up of the extracts was performed by a two-step procedure including silica gel adsorption and gel permeation chromatography. Finally, the target compounds were analyzed by gas chromatography combined with mass spectrometric detection. In addition, the complete analytical procedure was validated by parallel analysis of the certified reference material BCR 115. The results were in good accordance with the certified values. ASE could provide excellent extraction efficiency and good reproducibility in short time and with reduced organic solvent consumption.

Optimization of Accelerated Solvent Extraction for the Determination of Chlorinated Pesticides from Animal Feed

Electropolymerization and ion exchange properties of the polypyrrole film doped by para-toluene sulfonate (PPy/pTS) were investigated in aqueous solutions. The film with a column-like surface morphology was galvanostatically synthesized at 3 mA/cm2 during 1800 s. Cyclic voltammetric measurements of the PPy/pTS film in sodium para-toluene sulfonate (NapTS), tetraethylammonium chloride ((C2H5)4NCl), and NaCl aqueous solutions showed a cation exchange property, an anion exchange property, and a combination of them, respectively. Moreover, the large ions could decrease the transport of the small ions coexisting in the same solution, and the redox processes were proved to be electrochemically irreversible and ion transport-limiting reactions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2518–2522, 2006

Electropolymerization and ion exchange properties of a polypyrrole film doped by para-toluene sulfonate

Simultaneous desulfurization and denitrification from flue gas by catalytic ozonation combined with NH3/(NH4)2S2O8 absorption: Mechanisms and recovery of compound fertilizer.

Fouling and aging are the main causes for the degradation of heat exchanger performance from a well-behaved heat-transfer performance. They result in extra capital and energy costs for heat exchanger networks (HENs) to compensate for the gap in target temperatures. To reduce the negative effect of deposition, this paper presents a novel methodology for managing the cleaning schedule problem in the design of HENs. The method consists of three steps. First, obtain an original HEN using pseudotemperature enthalpy diagram approach. Then, simplify the structure of the original HEN through loop-breaking and small size unit eliminating strategies. Finally, optimize heat-transfer areas and cleaning schedules by considering the growth of deposits via a mixed integer nonlinear programming model. Therefore, the model is capable of weighing the capital cost for exchangers and the operation cost for both utility consumption and cleaning activities. In this study, two off-line cleaning alternatives with distinct cleani...

Fenglin Yang

Papers

Modified graphite electrode by polyaniline/tourmaline improves the performance of bio-cathode microbial fuel cell

Optimization of Accelerated Solvent Extraction for the Determination of Chlorinated Pesticides from Animal Feed

Electropolymerization and ion exchange properties of a polypyrrole film doped by para-toluene sulfonate

Simultaneous desulfurization and denitrification from flue gas by catalytic ozonation combined with NH3/(NH4)2S2O8 absorption: Mechanisms and recovery of compound fertilizer.

Synthesis of Heat Exchanger Networks Considering Fouling, Aging, and Cleaning