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Simultaneous precipitation (SP) using iron sulfates in the secondary treatment of elemental chlorine-free (ECF) kraft pulp mill wastewater was studied. In short-term pilot plant studies phosphorus reduction was improved from 58% up to 81% by adding 10 mgFe/L ferrous sulfate in the activated sludge (AS) process. The phosphorus reduction in full-scale experiment was about 80% when less than 10 mgFe/L was fed in with the influent of the AS plant. The reduction of phosphorus decreased with the dose of iron during the three month experiment. No notable change in either chemical oxygen demand (COD) or adsorbable organic halogen (AOX) reduction nor in the properties of sludge settling were observed during this SP experiment. Furthermore, no problems in sludge treatment due to increased iron concentrations in the waste sludge were reported. SP offers a simple way to decrease phosphorus discharges from AS plants instead of reliance on more expensive tertiary treatments.

Research in restoration and conservation is directed vs. more sustainable working materials, methods and technologies. Electrophoretic removal, from porous material, of undesired stains due to charged species is theoretically an interesting alternative to chemical cleaning methods, but the lack of specific and comprehensive research work leads to controversial opinions about the efficiency and the needed harmfulness for the treated objects. In this work paper, samples with artificial rust stains were subjected to electrophoretic cleaning treatments in mineral water as electrolyte. Treatments were carried out either in a bath by complete sample immersion between the distanced electrodes or by sample wetting and sandwiching between the electrodes. Evaluation of cleaning efficiency and treatment effects was based on colour change measurements (image analysis of scanned paper samples before and after the treatment and by colorimetric data via spectrophotometric measurements), investigation of morphological changes by SEM observations and folding endurance measurements.

A highly sensitive electrochemical (EC) biosensor combined with a 3D origami device for detection of Pb

This paper studies Fe/Al composite hydrogel electrode electrocoagulation (EC) and adsorption of alizarin red S (ARS). ARS removal efficiency and degradation mechanism when applying Fe/Al composite hydrogel electrode were investigated. The optimum experimental factors and degradation of ARS were discussed. ARS degradation was optimal operation at initial pH 3 with O2.The experimental results showed that the COD removal efficiency was better, reaching to about 90 % when applying the novel electrode system. The discoloration rate also reached the best effect of 99 % in the superior technical conditions. The optimum electrolysis time is about 30 min. Results revealed that the efficiency in the EC process with Fe/Al composite hydrogel electrodes were much better than that in conventional electrode system. In addition, Fe/Al composite hydrogel electrodes are environment-friendly material, which reuse waste and reduce cost. Hydrogel has certain iron exchange capacity to eliminate the residual metal irons. It is found that the application of ultrasonic helps to accelerate the electrocoagulation of ARS. This study not only realizes the ultrasonic, flotation, coagulation, and adsorption of the combination but also gains economy and environment. Consequently, the unique performance of Fe/Al composite hydrogel electrodes opens promising perspectives for fast, high, and economical treatment of wastewater containing dyes or/and organic contaminants.

Paper is one of the oldest and most abundant materials known to man. Recently, there has been a considerable interest in creating paper devices by combining paper with other functional materials. In this letter, we demonstrate a simple fabrication technique to create water-resistant ferro-patterns on wax paper using CO2 laser ablation. A resolution of about 100 mu m is achieved which is mostly limited by the cellulose fiber size (similar to 50 mu m) in the wax paper and can be improved by using a smaller cellulose matrix. Laser ablation results in modification of surface morphology and chemistry, leading to a change in surface energy. We also present a 2D model for ferrofluid deposition relating the size of the pattern to the amount of ferroparticles deposited on the surface. Finally, a paper gripper is presented to demonstrate advantages of our technique, which allows microscale patterning and machining in a single step.

A microfluidic paper-based analytical device (μPAD) fabricated by wax printing was designed to assess occupational exposure to metal-containing aerosols. This method employs rapid digestion of particulate metals using microliters of acid added directly to a punch taken from an air sampling filter. Punches were then placed on a μPAD, and digested metals were transported to detection reservoirs upon addition of water. These reservoirs contained reagents for colorimetric detection of Fe, Cu, and Ni. Dried buffer components were used to set the optimal pH in each detection reservoir, while precomplexation agents were deposited in the channels between the sample and detection zones to minimize interferences from competing metals. Metal concentrations were quantified from color intensity images using a scanner in conjunction with image processing software. Reproducible, log-linear calibration curves were generated for each metal, with method detection limits ranging from 1.0 to 1.5 μg for each metal (i.e., total mass present on the μPAD). Finally, a standard incineration ash sample was aerosolized, collected on filters, and analyzed for the three metals of interest. Analysis of this collected aerosol sample using a μPAD showed good correlation with known amounts of the metals present in the sample. This technology can provide rapid assessment of particulate metal concentrations at or below current regulatory limits and at dramatically reduced cost.

Laboratory studies were conducted to find out the efficacy of uniquely prepared zero valent iron impregnated silica in transforming xenobiotic chlorophenols namely 4-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol. Continuous mode column experiments were performed to investigate the transformation of chlorophenols by varying pH, column height, flow rate and initial chlorophenol concentration. Reusability study of the zero valent iron impregnated silica was studied as well as the morphological changes and the chemical composition of the catalyst medium were also investigated. Dechlorination kinetic studies were conducted and the order of dechlorination of chlorophenols was found to be 2,4,6-trichlorophenol > 2,4-dichlorophenol > 4-chlorophenol. The optimum pH, column height and flow rate were found to be 7, 20 cm and 0.75 L/hr respectively for all chlorophenols in the reaction duration of 4 hr. Intermediates formed during dechlorination study were identified by gas chromatography-mass spectroscopy analysis. This method was applied to real pulp and paper wastewater and was found satisfactory.

The objective of this World Bank technical assistance has been to support the Government of Bangladesh’s (GoB) national capacity development framework for improving water and sanitation services (WSS) in Bangladesh, focusing on demand-responsive peer-to-peer or horizontal learning processes and improve horizontal accountability communication and monitoring systems to track progress in the sector. This technical assistance is in line with the World Bank country assistance strategy (CAS) which seeks to support the GoB target of ensuring safe drinking water and sanitation for all. It has contributed to strengthening the long-term capacity of the government, in particular the union Parishad (UP) which is responsible for ensuring water and sanitation services for all in Bangladesh.

The precipitation of dissolved sulphide ions by electrocoagulation was studied at laboratory scale using pulp and paper mill wastewaters. Concentrations of dissolved organic carbon and phosphorus were analysed before and after the electrocoagulation process to examine the suitability of the process for treatment of sulphide odour from pulp and paper mill wastewater. The electrochemical cell used in this study was constructed from monopolar dissolving iron electrodes. The dissolved iron concentration was directly proportional to the applied electric charge (C/L) at the tested current densities. Electrochemically produced ferrous iron (Fe2+) precipitated dissolved sulphide ions efficiently. Electricity consumption of the treatment was 4-8 C/mg S(2-) while iron consumption was 1.1-2.2 mg/mg S(2-) during the initial phase of the sulphide precipitation when the applied electric charge was 10-60 C/L. When 60 C/L was applied, 88% of dissolved sulphides and 40% of phosphorus was precipitated. The reduction in DOC was low during the sulphide precipitation. According to these results, electrocoagulation can precipitate dissolved sulphides effectively and thereby reduce sulphide odours of pulp and paper mill wastewaters.

This work is first intended to optimize the experimental conditions for the maximum degradation of guaiacol (2-methoxyphenol) by Fenton's reagent, and second, to improve the process efficiency through the use of solar radiation. Guaiacol is considered as a model compound of pulp and paper mill effluent. The experiments were carried out in a laboratory-scale reactor subjected or not to solar radiation. Hydrogen peroxide solution was continuously introduced into the reactor at a constant flow rate. The kinetics of organic matter decay was evaluated by means of the chemical oxygen demand (COD) and the absorbance measurements. The experimental results showed that the Fenton and solar photo-Fenton systems lead successfully to 90% elimination of COD and absorbance at 604 nm from a guaiacol solution under particular experimental conditions. The COD removal always obeyed a pseudo-first-order kinetics. The effect of pH, temperature, H(2)O(2) dosing rate, initial concentration of Fe(2+), and initial COD was investigated using the Fenton process. The solar photo-Fenton system needed less time and consequently less quantity of H(2)O(2). Under the optimum experimental conditions, the solar photo-Fenton process needs a dose of H(2)O(2) 40% lower than that used in the Fenton process to remove 90% of COD.

We used toxicity identification evaluation (TIE) method to confirm the combinational effects of identified toxic metals in a paper recycling mill effluent in inducing the decreased lifespan in nematode Caenorhabditis elegans. Exposure to Ca + Al caused more severely decreased lifespan than that exposed to Ca, or Al; and exposure to Ca + Fe induced more severely decreased lifespan than that exposed to Ca, or Fe. Exposure to Ca+Al+Fe caused more severely decreased lifespan than that exposed to Ca, or Ca+Fe. Moreover, the baseline toxicity on lifespan was doubled by doubling the concentration of combined metals (Ca+Al+Fe) in spiking test in original effluent (oe), and lifespan defects in oe+Ca+Al+Fe exposed nematodes were more severe than that in Ca+Al+Fe exposed nematode. Therefore, Ca+Al+Fe exposure may largely explain the formation of decreased lifespan induced by the examined industrial effluent. Furthermore, the observed reduction of lifespan induced by the combination of high level of Ca with other metals may be at least partially independent of the insulin-like pathway.

The Taiwan Environmental Protection Administration (Taiwan EPA) launched a national Extended Producer Responsibility (EPR) system after integrating eight private recycling organizations in 1998. After that, the environmental performance of the EPR system brought a lot of attention to policy makers. Many studies show positive environmental effects of the EPR system in Taiwan. However, there are controversial questions remained, such as whether the performance indicators used are the right choice to estimate the environmental effects of the recycling policy? Can those estimated results really reflect the performance of the system? This paper would therefore like to more accurately evaluate the performance indicators of the EPR system based on data observed over the past decade in Taiwan. In the process of evaluating the performance indicators, we have found that the collection rates for durable goods are often ignored in countries that pursue a zero waste policy. This may affect the actual recycling outcome and resource direction targeted by producers. However, in order for the collection rate to be adopted as a policy indicator, how to estimate the amounts of retired or waste products during a period is critical. In this paper, we estimate the collection rate for electrical and electronic waste by using the survival analysis and ownership data analysis approaches. We also provide a comparison of both approaches and put forward suggestions for directions in the future in solid waste management.

Iron, an essential element for life, is regulated primarily at the level of uptake, storage, and transport in order to maintain sufficient availability for normal physiology. The key protein in iron homeostasis is a 25-amino-acid peptide, hepcidin, which modulates the amount of iron in the circulation by binding and promoting the degradation of the iron exporter ferroportin. Given the central importance of hepcidin, recent studies have focused on how iron is sensed and how the iron signal is transmitted to hepcidin. Mutations in a type II serine protease, matriptase-2/TMPRSS6, were recently identified to be associated with severe iron deficiency caused by inappropriately high levels of hepcidin expression. A key biologically relevant substrate for the proteolytic activity of matriptase-2/TMPRSS6 was found to be hemojuvelin, a cell surface protein that regulates hepcidin expression through a BMP/SMAD pathway. In this review, we discuss the putative role of matriptase-2/TMPRSS6 in iron homeostasis.

Metal salts, ferrous sulphate and aluminium chloride, were added to laboratory-scale activated sludge plant treating paper mill effluents to investigate the effect on settlement characteristics. Before treatment the sludge was filamentous, had stirred sludge volume index (SSVI) values in excess of 300 and was moderately hydrophobic. The use of FeSO 4 · 7H 2 O took three weeks to reduce the SSVI to 90. Microscopic examination showed that Fe had converted the filamentous flocs into a compact structure. When the iron dosing was stopped, the sludge returned to its bulking state within four weeks. In a subsequent trial, the addition of AlCl 3 initially resulted in an improvement of the settlement index but then caused deterioration of the sludge properties. It is possible that aluminium was overdosed and caused charge reversal, increasing the SSVI.

The bleaching wastewater effluent from a pulp and paper mill (located in Tianjin, China) was treated with solar photo-Fenton process in a lab-scale reactor (22 cm x 15 cm thermostatic dish). The mill used wastepaper as raw material and the effluent contained 332 mgL(-1) of total organic carbon (TOC) and 1286 mg L(-1) of COD. The treatment involved a constant intensity of irradiation (0.2 kW/m(2)) with a solar simulator of 250 W xenon lamp and various conditions of pH, temperature, and initial concentrations of H(2)O(2) and Fe(II). The better treatment conditions were searched for in the ranges of initial Fe(II) concentration from 31 to 310 mgL(-1) (initial pH 3.0, 30 degrees C), initial H(2)O(2) concentration from 0.5 to 3 Dth (1 Dth=1883 mg L(-1) for TOC mineralization) (initial pH 3.0, 30 degrees C), initial pH from 2.0 to 6.0 (1 and 2 Dth, 10:1 of H(2)O(2)/Fe(II), 30 degrees C), and temperature from 30 to 50 degrees C (1 Dth, 10:1 of H(2)O(2)/Fe(II), initial pH 2.8). TOC removal generally showed the initial fast increase stage within the first sampling time of 15 min, followed by the gradual increase stage in the remaining sampling time of 180 min experimental time course. The highest percentage of TOC removal in the first stage was about 60% when the initial pH was either 2.8 (H(2)O(2)=1 Dth, ratio=10:1, temperature=30-50 degrees C) or 3.5 (H(2)O(2)=2 Dth, ratio=10:1, temperature=30 degrees C). Also under the latter condition, the value reached 82% at 120 min and was projected to reach 94% at 180 min. According to the positive effect of temperature increase on TOC removal observed in this experiment, further increase above these maximum values is possible if the temperature of the above condition were increased from 30 to 40 degrees C or 50 degrees C. Furthermore, under most of the treatment conditions, the TOC removal reached or was projected to reach over 60% toward the end of the experiments. The result indicated that the solar photo-Fenton process has a potential to effectively remove TOC from the wastepaper pulp effluent on a large scale.

The main objective of this work is to study the technical viability of using the effluent generated in paper machines (white water) in the wash presses of the bleaching stage, reducing fresh water consumption. As a case study, the industrial process of Ripasa S.A. Celulose e Papel was evaluated. White water rate is about 700 m3/h and it is not possible to reuse all this volume in the bleaching stage without causing operational problems (fouling in tubes and clogging in the screens). A mass balance of the bleaching unit was developed in an electronic spreadsheet in order to evaluate the possibility of reducing fresh water consumption, using only a fraction of the available white water in the wash presses. To achieve this objective some physical-chemistry properties of the white water stream and of other streams of the process were determined. The maximum concentration of some non-process elements (Si, Ca, Mn and Fe), which could accumulate in the process, were determined in order to establish some parameters to allow process integration of the streams involved, considering operational constraints. The results obtained have shown that it is possible to reduce approximately by 13% the consumption of fresh water and this methodology has been satisfactory.

Exposure to metal-containing aerosols has been linked with adverse health outcomes for almost every organ in the human body. Commercially available techniques for quantifying particulate metals are time-intensive, laborious, and expensive; often sample analysis exceeds $100. We report a simple technique, based upon a distance-based detection motif, for quantifying metal concentrations of Ni, Cu, and Fe in airborne particulate matter using microfluidic paper-based analytical devices. Paper substrates are used to create sensors that are self-contained, self-timing, and require only a drop of sample for operation. Unlike other colorimetric approaches in paper microfluidics that rely on optical instrumentation for analysis, with distance-based detection, analyte is quantified visually based on the distance of a colorimetric reaction, similar to reading temperature on a thermometer. To demonstrate the effectiveness of this approach, Ni, Cu, and Fe were measured individually in single-channel devices; detection limits as low as 0.1, 0.1, and 0.05 μg were reported for Ni, Cu, and Fe. Multiplexed analysis of all three metals was achieved with detection limits of 1, 5, and 1 μg for Ni, Cu, and Fe. We also extended the dynamic range for multi-analyte detection by printing concentration gradients of colorimetric reagents using an off-the-shelf inkjet printer. Analyte selectivity was demonstrated for common interferences. To demonstrate utility of the method, Ni, Cu, and Fe were measured from samples of certified welding fume; levels measured with paper sensors matched known values determined gravimetrically.

The presence of transition metals during the hydrogen peroxide bleaching of pulp results in the decomposition of hydrogen peroxide, which decreases the bleaching efficiency. In this study, chitosans were used as peroxide stabilizer in the alkaline hydrogen peroxide bleaching of aspen chemithermomechanical pulp (CTMP). The results showed that the brightness of the bleached CTMP increased 1.5% ISO by addition of 0.1% chitosan with 95% degree of deacetylation during peroxide bleaching. Transition metals in the form of ions or metal colloid particles, such as iron, copper and manganese, could be adsorbed by chitosans. Chitosans could inhibit the decomposition of hydrogen peroxide catalyzed by different transition metals under alkaline conditions. The ability of chitosans to inhibit peroxide decomposition depended on the type of transition metals, chitosan concentration and degree of deacetylation applied. The addition of chitosan slightly reduced the concentration of the hydroxyl radical formed during the hydrogen peroxide bleaching of aspen CTMP.

In this study, the combination of Fe(3+)/HCl and ultrasonic treatment was applied to selectively hydrolyze cellulose for the preparation of microcrystalline cellulose (MCC). It was found that the crystallinity and specific surface area of hydrocellulose samples were higher (78.92% and 2.23581 m(2)g(-1), respectively), compared with the method that only used Fe(3+)/HCl catalyst without ultrasonic treatment. Meanwhile, the hydrolysate can be extracted and reused for cellulose hydrolysis for three runs, which was effective in saving the dosage of chemicals and reducing the pollution of the environment without affecting the properties of hydrocellulose. Moreover, the increased concentration of total reducing sugar (TRS) after three runs may be used as a valuable source in biofuels production. The technology of cellulose hydrolysis, by retaining the crystalline region for MCC products while promoting hydrolysis of amorphous region for further utilization is of great novelty, which may prove valuable in converting biomass into chemicals and biofuels, environmentally and economically.

This paper reports the continuous reductive amination of different molecules, including biomass-related compounds, over carbon-supported FeNi nanoparticles obtained on the basis of inexpensive and abundant metal precursors and cellulose. A biorefinery case study for the preparation of pyrrolidones via acid-catalyzed hydrolysis of glucose followed by reductive amination of the obtained levulinic acid is described.

The electrochemical oxidation of phenol in synthetic wastewater and paper mill wastewater catalyzed by metal ion supported on cation exchange resin in suspended bed electrolytic reactor with graphite electrode has been investigated. The catalyst was characterized by SEM and XPS spectra and the effects of pH, the different metal ion and NaCl on the efficiency of the electrochemical oxidation phenol process were also studied. It was found that the catalyst containing Fe3+ had the highest electrochemical catalytic activity for the electrochemical oxidation of phenol. When the initial concentration of phenol was 200 ppm, up to 90% chemical oxygen demand (COD) removal was obtained in 10 min. When the catalyst containing Fe3+ was used to the paper mill wastewater, it still showed high efficiency. The COD removal could get to 75% in 60 min.

The effect of Fenton's reagent (FR) on surface and dispersion properties of black liquor (BL) was investigated. These properties were compared to those of indulin C (IC), a commercial lignin, and egg lecithin (Le). FR was applied at two different bulk concentrations of H2O2 (160 and 320 mM). At pH 8, a minimum in surface tension for the Fenton treated BL was observed. The dispersant ability of BL, IC and Le in oil-in-water (O/W) emulsions was studied by measuring emulsion stability and drop size. It was found that the surface activity and emulsifying capability of BL were higher than those of IC. The emulsifying capability of Le was improved by the FR treatment at low H2O2 concentration.

Different advanced oxidation processes (AOPs) have been applied to remove the organic carbon content of a paper mill effluent originating from the Kraft pulp bleaching process. The considered AOPs were: TiO2-mediated heterogeneous photocatalysis, TiO2-mediated heterogeneous photocatalysis assisted with H2O2, TiO2-mediated heterogeneous photocatalysis coupled with Fenton, photo-Fenton, ozonation and ozonation with UV-A light irradiation. The application of the selected AOPs all resulted in a considerable decrease in dissolved organic carbon (DOC) content with variable treatment efficiencies depending upon the nature/type of the applied AOP. A Life Cycle Assessment (LCA) study was used as a tool to compare the different AOPs in terms of their environmental impact. Heterogeneous photocatalysis coupled with the Fenton’s reagent proved to have the lowest environmental impact accompanied with a moderate-to-high DOC removal rate. On the other hand, heterogeneous photocatalysis appeared to be the worst AOP both in terms of DOC abatement rate and environmental impact. For the studied AOPs, LCA has indicated that the environmental impact was attributable to the high electrical energy (power) consumption necessary to run a UV-A lamp or to produce ozone.

A radiotracer method was applied to the measurement of inorganic contaminants migrating into food. The method was applied to the study of 10 samples of recycled paper and board. The only elements detected in the static migration test were zinc and iron, at concentrations close to the detection limit. Samples of rice, oats, custard powder, mushrooms and fries showed that traces of these elements had migrated from the packaging. The migration was limited to less than 1%, with the exception of the mushrooms, where the decomposition of the food had resulted in a 12.5% transfer of zinc from the mushroom bag after 8 days, equivalent to migration of 0.022 mg dm(-2). Shaking had no effect on migration, except in one case of custard powder where migration occurred at a level equivalent to 0.002 mg dm(-2). The maximum migration determined in the present study was 4.8 microg zinc and 2.6 microg iron, which is negligible when compared with the recommended daily intakes of 15 and 14 mg, respectively. When Tenax was tested as a food simulant, no zinc was detected (0.001 mg dm(-2)), although slight migration (0.001 mg dm(-2)) occurred into food.

While recent evidence indicates that the generation of reactive oxygen species (ROS) and associated oxidative damage are frequently observed in fish populations with exposure to pulp and paper mill effluents, the potential for ROS generation from municipal sewage effluents has not been addressed. This study investigates the utility of measures of oxidative stress in delineating the effects of both pulp and paper mill and municipal sewage discharges. Longnose sucker (Catostomus catostomus) were collected below three pulp and paper mill and two municipal sewage effluent discharges over a 3-year period within the Wapiti and Athabasca River systems in northern Alberta. Biochemical responses in longnose sucker varied between the two rivers systems, with more pronounced changes occurring within the Wapiti River. Of the suite of biochemical parameters examined, fatty acyl-CoA oxidase (FAO) activity was the most sensitive indicator of pulp and paper mill exposure, but was only infrequently induced with exposure to municipal sewage effluent. Hepatic and gonadal 2-thiobarbituric acid reactive substances, lipid hydroperoxides, and hepatic free iron were less consistently elevated with exposure to pulp and paper mill effluent than FAO activity, and were also only infrequently altered with sewage effluent exposure. Hepatic ascorbic acid, liver somatic index, and condition factor were consistently altered with exposure to both sewage and pulp and paper mill effluents. While specific biochemical and organismal responses varied with effluents and time, the collective suite of oxidative stress endpoints proved to be useful tools in identifying relative influences of municipal sewage and pulp and paper mill effluent on fish populations in adjacent receiving waters.

Changes in material use, energy use and emissions profiles of industry are the result of complex interrelationships among a multitude of technological and economic drivers. To better understand and guide such changes requires that attention is paid to the time-varying consequences that technology and economic influences have on an industry's choice of inputs and its associated (desired and undesired) outputs. This paper lays out an approach to improving our understanding of the dynamics of large industrial systems. The approach combines engineering and econometric analysis with a detailed representation of an industry's capital stock structure. A transparent dynamic computer modeling approach is chosen to integrate information from these analyses in ways that foster participation of stakeholders from industry and government agencies in all stages of the modeling process-from problem definition and determination of system boundaries to generation of scenarios and interpretation of results. Three case studies of industrial energy use in the USA are presented-one each for the iron and steel, pulp and paper, and ethylene industry. Dynamic models of these industries are described and then used to investigate alternative carbon emissions and investment-led policies. A comparison of results clearly points towards two key issues: the need for industry specific policy approaches in order to effectively influence industrial energy use, fuel mix and carbon emissions, and the need for longer time horizons than have typically been chosen for the analysis of industrial responses to climate change policies.

An alkalophilic Aspergillus nidulans KK-99 produced an alkaline, thermostable xylanase (40 IU/ml) in a basal medium supplemented with wheat bran (2% w/v) and KNO3 (at 0.15% N) pH 10.0 and 37 degrees C. The partially purified xylanase was optimally active at pH 8.0 and 55 degrees C. The xylanase was stable in a broad pH range of 4.0-9.5 for 1 h at 55 degrees C, retaining more than 80% of its activity. The enzyme exhibited greater binding affinity for xylan from hardwood than from softwood. The xylanase activity was stimulated (+25%) by Na+ and Fe2+ and was strongly inhibited (maximum by 70%) by Tween-20, 40, 60, SDS, acetic anhydride, phenylmethane sulphonyl fluoride, Triton-X-100. The xylanase dose of 1.0 IU/g dry weight pulp gave optimum bleach boosting of Kraft pulp at pH 8.0 and temperature 55 degrees C for 3 h reaction time.

Where malaria surveillance and health care is inadequate, iron supplements given without food can increase the severity of malarial infections. The likely explanation is that the rate of iron influx into the plasma from high-dose oral supplements exceeds the rate of iron binding to transferrin and a quantity of non-transferrin-bound iron (NTBI) is formed. It is proposed that NTBI increases the intensity of malarial infections by increasing the sequestration of malaria-infected red cells in the capillaries of the brain and intestine, causing more cerebral malaria and further increasing the permeability of the intestinal barrier to the passage of pathogens. Bacteremia is frequently reported in children with severe malaria. At the same time, high iron doses stimulate the growth of pathogenic bacteria in the stool, further increasing the potential for bacteremia. The normal immune response to malaria, as well as other infections and inflammatory disorders, is to prevent further microbial growth by stimulating hepcidin synthesis and preventing the passage of iron into the plasma. Iron absorption is decreased and the efficacy of the iron interventions would be expected to be lower in the presence of infections.

The paper production is material intensive and generates enormous quantity of wastewater containing organic pollutants and heavy metals. Present study demonstrates the feasibility of constructed wetlands (CWs) to treat the heavy metals from pulp and paper industry effluent by using vertical flow constructed wetlands planted with commonly available macrophytes such as Typha angustifolia, Erianthus arundinaceus, and Phragmites australis. Results indicate that the removal efficiencies of the planted CWs for iron, copper, manganese, zinc, nickel, and cadmium were 74, 80, 60, 70, 71, and 70 %, respectively. On the other hand, the removal efficiency of the unplanted system was significantly lower ranging between 31 and 55 %. Among the macrophytes, T. angustifolia and E. arundinaceus exhibited comparatively higher bioconcentration factor (10(2) to 10(3)) than P. australis.

The zero-valent iron magnetic biochar composites (ZVI-MBC) were synthesized from the paper mill sludge biochar and used for the treatment of the synthetic and real effluent containing pentachlorophenol (PCP). During the synthesis of ZVI-MBC, NaBH4 was used as the reducing agent to reduce Fe(II) to Fe(0) and cetyltrimethylammonium bromide was added as surfactant. The effect of the molar ratio of FeSO4 to NaBH4, dose of the surfactant and the ZVI to biochar ratio on the PCP removal efficiency was investigated. It was found that the ZVI-MBC combines the advantages of biochar and ZVI particles for the simultaneous adsorption and dechlorination of PCP in the effluent and the complete removal of PCP was obtained. The ageing tests showed that biochar prevents the formation of oxide film on the ZVI particles and leaching tests confirmed the stability of ZVI on biochar matrix as very low iron leaching was noticed.

International audience; This article presents the case of blue paper in a sample book that once belonged to Victor Poterlet, a French wallpaper designer operating in Paris in the 19th century. Prussian blue is the main colourant used to dye the paper. The condition of the paper is very poor, probably due to the presence of free iron ions. However the paper could not be replaced or chemically treated because it supports 954 samples, which could not be dismantled due to time considerations. Moreover the paper is indubitably of high aesthetic value and an inherent part of the original. This study was carried out in order to optimise the reinforcement of the blue paper through local treatments, such as resizing and/or lining. Tests were also undertaken to evaluate improvements in mechanical properties induced by these treatments. In addition it was found necessary to estimate any colour changes that could result from the application of an adhesive to a deep blue paper. Several adhesives were evaluated: Tylose, Klucel, gelatine, starch, Funori, Lascaux 498HV and Lascaux 360HV. The best results were obtained with Tylose. Finally, the book was consolidated with linings that were applied by reactivating the adhesive. This method offered a satisfactorily compromise between the best reinforcement and the least colour change

The synergistic mechanism of 2, 4, 6-trichlorophenol (TCP) degradation using a combination of Fe0 and anaerobic dechlorinating bacteria with batch processing was investigated. Experimental results showed that under the conditions of pH 7.0, Fe0 5 g x L(-1) and 2,4,6-TCP 30 mg x L(-1), the growth and interface enrichment of enriched-bacteria could be promoted by Fe0, the cell mass (expressed by D600) of Fe0/enriched-bacteria was about 1.7 times as high as that of the individual predominant groups of dechlorinating bacteria. After 96 h reaction, large amount of bacteria attached to the iron surface, with short rod or coccus-like morphology. The pH value of the system was maintained at 7.8, which could be beneficial to the reductive dechlorination reaction and the growth of the enriched-bacteria. The major pathway of 2,4,6-TCP degradation in the Fe0/enriched-bacteria system was 2,4,6-TCP to 2,4-DCP and then to 4-CP.

According to current environmental legislation concerned with water scarcity, paper industry is being forced to adopt a zero liquid effluent policy. In consequence, reverse osmosis (RO) systems are being assessed as the final step of effluent treatment trains aiming to recover final wastewater and reuse it as process water. One of the most important drawbacks of these treatments is the production of a retentated stream, which is usually highly loaded with biorecalcitrant organic matter and inorganics; and this effluent must meet current legislation stringent constraints before being ultimately disposed. The treatment of biorefractory RO retentate from a paper mill by several promising advanced oxidation processes (AOPs) – conventional Fenton, photo-Fenton and photocatalysis – was optimized considering the effect and interaction of reaction parameters; particularly using response surface methodology (RSM) when appropriate (Fenton processes). The economical cost of these treatments was also comparatively assessed. Photo-Fenton process was able to totally remove the COD of the retentate, and resulted even operatively cheaper at high COD removal levels than conventional Fenton, which achieved an 80% reduction of the COD at best. In addition, although these optimal results were produced at pH = 2.8, it was also tested that Fenton processes are able to achieve good COD reduction efficiencies (>60%) without adjusting the initial pH value, provided the natural pH of this wastewater was close to neutral. Finally, although TiO2-photocatalysis showed the least efficient and most expensive figures, it improved the biodegradability of the retentate, so its combination with a final biological step almost achieved the total removal of the COD.

Advanced oxidation processes including UV, UV/H(2)O(2), Fenton reaction (Fe(II)/H(2)O(2)) and photo-Fenton process (Fe(II)/H(2)O(2)/UV) for the treatment of paper mill wastewater will be investigated. A comparison among these techniques is undertaken with respect to the decrease of chemical oxygen demand (COD) and total suspended solids (TSS) and the evolution of chloride ions. Optimum operating conditions for each process under study revealed the effect of the initial amounts of Fe(II) and hydrogen peroxide. Of the tested processes, photo-Fenton process was found to be the fastest one with respect to COD and TSS reduction of the wastewater within 45 min reaction time under low amounts of Fe(II) and hydrogen peroxide of 0.5 and 1.5mg/L, respectively, and amounted to 79.6% and 96.6% COD and TSS removal. The initial biodegradability of the organic matter present in the effluent, estimated as the BOD(5)/COD, was low 0.21. When the effluent was submitted to the different types of AOPs used in this study, the biodegradability increases significantly. Within 45 min of reaction time, the photo-Fenton process appears as the most efficient process in the enhancement of the biodegradability of the organic matter in the effluent and the BOD(5)/COD ratio increased from 0.21 to 0.7.

The efficiency of advanced oxidation processes (AOPs), enzymatic treatment and combined enzymatic/AOP sequences for the colour remediation of soda and chemimechanical pulp and paper mill effluent was investigated. The results indicated that under all circumstances, the AOP using ultraviolet irradiation (photo‐Fenton) was more efficient in the degradation of effluent components in comparison with the dark reaction. It was found that both versatile peroxidase (VP) from Bjerkandera adusta and laccase from Trametes versicolor, as pure enzymes, decolorize the deep brown effluent to a clear light‐yellow solution. In addition, it was found that in the laccase treatment, the decolorization rates of both effluents were enhanced in the presence of 2, 2’‐azinobis (3‐ethylbenzthiazoline‐6‐sulfonate), while in the case of by VP, Mn+2 decreased the efficiency of the decolorization treatment. The concomitant use of enzymes and AOPs imposes a considerable effect on the colour remediation of effluent samples.

Hepcidin is the central regulator of systemic iron homeostasis. Dysregulation of hepcidin production results in a variety of iron disorders. Hepcidin deficiency is the cause of iron overload in hereditary hemochromatosis, iron-loading anemias, and hepatitis C. Hepcidin excess is associated with anemia of inflammation, chronic kidney disease and iron-refractory iron deficiency anemia. Diagnostic and therapeutic applications of this new knowledge are beginning to emerge. Dr. Ernest Beutler played a significant role in advancing our understanding of the function of hepcidin. This review is dedicated to his memory.

International audience; The experimentation with new ideas and techniques in contem-p o r a ry art can lead to substantial conservation issues in the near f u t u re, especially when the artist tries to fuse two incompatible materials into one object. This is the case with the 'Print of thre e rusted iron plates', created by the French contemporary art i s t B e rn a rd Pagès and now in the Museum of Modern Art, Saint Etienne, France. Although contemporary, this print alre a d y shows serious damage caused by the presence of iron in the p a p e r. It was so brittle that it could no longer be handled nor be displayed. This type of artefact raises fundamental questions for paper conservators: its degradation is extremely rapid and inherent to the combination of its constituents (iron compounds and paper) that obviously cannot be separated. It also necessitates investigation into the possibilities of using available chemical t reatments in order to limit the degradation mechanisms while keeping in mind that the visual appearance should re m a i n unchanged. Historical Background 'Print of three rusted iron plates' is one of the series of prints and drawings created in the 1970's by Bern a rd Pagès while he was working under the influence of the avant-garde, Support s / S u r-faces' gro u p (Abadie 1999; Exhibition catalogue, 19 91, 2002). A s an established sculptor, he worked with raw materials and tried to escape from personal expression by using printing methods that place the object in the centre of the creation process. These methods consisted of etching a hydrochloric acid solution on steel plates in order to encourage the formation of rust. These plates were then pressed on the paper, producing prints of ru s t. F i n a l l y, the artwork was completed with graphite pencil and black ink lines that emphasised the borders of the central plate (Fig 1). Description of the Arte f a c t F rom a chemical point of view, the work is in fact a thick ru s t layer embedded in a contemporary wove paper, commonly known as 'Vélin d'Arches' and manufactured by C a n s o n. One edge features a watermark, 'Dessin-Ja-Arches-France'. The paper is now very brittle and fractured in many places. Two pieces are missing. The sharpness of the edges shows that the frac-t u res are due to loss of paper flexibility. Raking light observ a t i o n revealed undulations. Unprinted areas are light brown and hig-' E m p reinte de trois plaques de fer rouillées' (Print of three ru s t e d i ron plates) was produced in the 1970's by the artist Bern a rd Pagès according to a specific protocol: steel plates were etched with a hydrochloric acid solution then pressed onto paper to create ru s t prints. Although contemporary, this work of art already shows serious damage caused by the presence of iron in the paper. Various conservation treatment possibilities were explored to pre-s e rve the artefact. Replicas were made and used to evaluate the dif-f e rent options. The application of the calcium phytate tre a t m e n t , initially developed for iron gall ink corroded manuscripts, was investigated and it turned out to be efficient in preventing degradation of the replicas. The addition of alcohol to the treatment solutions was also considered, but was eventually not tested, as it tends to decrease the treatment effectiveness. It was finally decided to use pure aqueous solutions and to float the artefact during the treatment. The treatment was undertaken twice without inducing any visual changes to the artefact. Some free iron (II) still remained in the paper after treatment but to a much lesser extent than before treatment. This suggests that the intervention was at least partially effective. As the artefact re q u i red consolidation and lining, the capabilities of several commonly used adhesives that change paper sensitivity to water were evaluated and compare d. Gelatine was finally chosen for consolidation as it renders the paper the most hydrophobic compared with starch, hydro x y p ro-pylcellulose or methylcellulose. After lining, the artefact was mounted in a frame specially designed for safe display.

This study attempts to evaluate the applicability of chemical oxidation processes to polish biologically treated effluent of a plant manufacturing hardboard from waste paper to comply with the discharge limit of 120 mg l−1 chemical oxygen demand (COD). In the first step, a chemically assisted settling was applied. The optimum results were obtained with alum plus lime with the alum dose of 200 mg l−1. In the second step, chemically assisted settling effluent was fed into an activated sludge system and over 80% COD removal was achieved. In the last step of the experimental study, a series of ozone oxidation and Fenton oxidation methods were tested to remove residual COD. Ozone oxidation provided 80% COD removal. An ozone dose of 40 mg min−1 with a reaction time of two hours was found to be optimum. Catalytic ozonation by using ferric iron, as well as high pH ozonation, Fenton process and H2O2/O3 oxidation did not prove to be more efficient than plain ozonation under these study conditions.

Colour and COD removal studies of pulp and paper mill effluent were carried out by Fenton's oxidation. Fenton's oxidation process was employed in four distinct stages interrelated to each other. In the first stage, FeSO4 concentration, pH and temperature were kept constant to determine H2O2 dose for maximum color and COD removal. In the second stage, dose of H2O2 obtained from first stage and same oxidation conditions were applied to determine the optimum FeSO4 concentration. Optimum pH, temperature and contact time were investigated in third and fourth stages considering the results of optimum doses of first and second stage. Maximum color up to 98% and COD removal up to 62% were obtained for Fenton reagents of 600 mg/L of H2O2 and 100 mg/L of Fe2+ dose at pH 3.0 for 300 min of contact period between reagents and effluent.

This study aims to investigate the treatment of paper mill effluents using electrocoagulation. Removal of lignin, phenol, chemical oxygen demand (COD) and biological oxygen demand (BOD) from paper mill effluents was investigated at various current intensities by using different electrodes (Al and Fe) and at various electrolysis times (1.0, 2.5, 5.0 and 7.5 min). It was observed that the experiments carried out at 12 V, an electrolysis time of 2 min and a current intensity of 77.13 mA were sufficient for the removal of these pollutants with each electrode. The removal capacities of the process using an Al electrode were 80% of lignin, 98% of phenol, 70% of BOD, and 75% of COD after 7.5 min. Using an Fe electrode the removal capacities were 92%, 93%, 80% and 55%, respectively. In addition, it was found that removal of lignin, phenol, BOD and COD increased with increasing current intensity. In the experiments carried out at different current intensities, higher removal can be explained through a decrease in intra-resistance of solution and consequently an increase at the transfer speed of organic species to electrodes. It was also found that Al electrode performs higher efficiency than Fe electrode except for COD removal. However, the time required for removal of BOD was more than that of COD. The results suggest that electrocoagulation could be considered as an effective alternative to paper mill effluents treatment. © 2007 Elsevier Ltd. All rights reserved.

The aim of this work was to evaluate the effect of chelator mediated-Fenton reaction (CMFR) on the chemical oxygen demand (COD) removal from bleaching kraft mill effluent. Effluent treatments were carried out to study the effect of the chelator 3, 4-dihydroxyphenylacetic acid (DOPAC), Fe3 + and H2O2 concentrations on COD removal. For optimization of COD removal, the methodology of statistical experimental design was employed. The estimated second-order polynomial multiple regression model predicts a maximum COD removal of 75.5% (COD/COD0 = 0.245) at the confidence level of 95%. Analysis of variance (ANOVA) showed a good coefficient of determination (R2) value of 0.90, thus ensuring a satisfactory adjustment of the second-order regression model with the experimental data. Indeed, CMFR proved to be a potential process to treat industrial effluents characterized by its high COD.

International audience; This tutorial review intends to show, through demonstrative examples chosen from the recent literature, how surface characterisation conducted by modern investigation methods leads to very rich information on a cultural heritage artefact's history, fabrication techniques and conservation state. Application of surface science to conservation science is of great help for the definition of a conservation and restoration policy for museum and archaeological objects. A brief description of the investigation methods is given, together with relevant references for more detailed information.

Most arsenic bearing solid residuals (ABSR) from water treatment will be disposed in nonhazardous landfills. The lack of an appropriate leaching test to predict arsenic mobilization from ABSR creates a need to evaluate the magnitude and mechanisms of arsenic release under landfill conditions. This work studies the leaching of arsenic and iron from a common ABSR, granular ferric hydroxide, in a laboratory-scale column that simulates the biological and physicochemical conditions of a mature, mixed solid waste landfill. The column operated for approximately 900 days and the mode of transport as well as chemical speciation of iron and arsenic changed with column age. Both iron and arsenic were readily mobilized under the anaerobic, reducing conditions. During the early stages of operation, most arsenic and iron leaching (80% and 65%, respectively) was associated with suspended particulate matter, and iron was lost proportionately faster than arsenic. In later stages, while the rate of iron leaching declined, the arsenic leaching rate increased greater than 7-fold. The final phase was characterized by dissolved species leaching. Future work on the development of standard batch leaching tests should take into account the dominant mobilization mechanisms identified in this work: solid associated transport, reductive sorbent dissolution, and microbially mediated arsenic reduction.

Pulp mill effluent containing toxic chemicals was treated by different advanced oxidation processes (AOPs) consisting of treatments by hydrogen peroxide, Fenton's reagent (H2O2/Fe2+), UV, UV/H2O2, photo-Fenton (UV/H2O2/Fe2+), ozonation and peroxone (ozone/H2O2) in laboratory-scale reactors for color, total organic carbon (TOC) and adsorbable organic halogens (AOX) removals from the pulp mill effluent. Effects of some operating parameters such as the initial pH, oxidant and catalyst concentrations on TOC, color, AOX removals were investigated. Almost every method used resulted in some degree of color removal from the pulp mill effluent. However, the Fenton's reagent utilizing H2O2/Fe2+ resulted in the highest color, TOC and AOX removals under acidic conditions when compared with the other AOPs tested. Approximately, 88% TOC, 85% color and 89% AOX removals were obtained by the Fenton's reagent at pH 5 within 30 min. Photo-Fenton process yielded comparable TOC (85%), color (82%) and AOX (93%) removals within 5 min due to oxidations by UV light in addition to the Fenton's reagent. Fast oxidation reactions by the photo-Fenton treatment makes this approach more favorable as compared to the others used. (c) 2006 Elsevier B.V. All rights reserved.

The effect of Kraft black liquor on the lipid peroxidation of rat homogenates was examined. The lipid peroxidation of homogenates from different organs (kidney, brain, lung, and liver) was induced by Fenton's reagent. The products of lipid peroxidation, lipid hydroperoxides and TBARS were measured by FOX method and TBA assay, respectively. It was found that black liquor significantly reduced the concentration of TBARS, but not the concentration of lipid hydroperoxides. This inhibition was directly proportional to the concentration of Kraft black liquor and the incubation temperature. Conclusively, the black liquor from pulp and paper industry exhibited an antioxidant activity.

This study investigates the temporal onset of reactive oxygen species (ROS) damage and changes in circulating sex steroids in immature rainbow trout exposed over 21 d to two pulp-mill effluents. Exposure to effluent from a bleached sulfite mill produced increases in 2-thiobarbituric acid reactive substances (TBARS), ethoxyresorufin O-deethylase (EROD) activity, hepatic free iron, and significant depressions in hepatic ascorbic acid. Impairments in pregnenolone production relative to cholesterol availability suggest an effect of sulfite-mill effluent early in the steroidogenic pathway. Induction of vitellogenin in immature fish exposed to effluent from this mill, relative to waterborne 17 beta-estradiol treatments, indicated sulfite-mill effluent contained constituents capable of binding the estrogen receptor. Exposure to a kraft-mill effluent also elevated hepatic TBARS, tissue normalized fatty acyl-coenzyme A oxidase (FAO) activity, and hepatic free iron while producing commensurate declines in hepatic ascorbic acid. Plasma testosterone, 11-ketotestosterone, and 17 beta-estradiol were elevated with kraft-mill effluent exposure, but no changes in vitellogenin induction were observed. In summary, effluent from bleached sulfite and bleached kraft mills yielded similar oxidative stress responses, but marked differences were observed in the endocrine-disrupting potential of each effluent.

Iron is an important component of the Earth's crust, but its own chemistry greatly limits utilisation and also sets the basis for its toxicity. The capacity of readily exchanging electrons in aerobic conditions makes iron essential for fundamental cell functions, such as DNA synthesis, transport of oxygen and electrons, and cell respiration. On the other hand, as humans have no means to control iron excretion, excess iron, regardless of the route of entry, accumulates in parenchymal organs and threatens cell viability. In fact, a number of disease states (that is, iron overload diseases) attributable to genetic or acquired factors are pathogenetically linked to excess body iron stores and iron removal therapy is an effective lifesaving strategy in such circumstances.