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This study explored the production of activated carbon from agricultural waste, specifically Punica granatum peel, and its application as an eco-friendly solution for removing copper (Cu2+) ions from industrial effluents, particularly those from copper-plating industries. The Punica granatum peel was chemically activated using ortho-phosphoric acid to produce activated carbon. The activation process involved impregnation followed by thermal activation at 500 °C. The resultant activated carbon was characterized using FTIR, TGA/DTA, and adsorption tests at room temperature and pH 5, which demonstrated a Cu2+ ion retention rate exceeding 95% within the first 15 minutes. The adsorption kinetics were analyzed using pseudo-first-order and pseudo-second-order models, while the adsorption isotherms was examined using Langmuir and Freundlich models. The study demonstrated that the activated carbon derived from Punica granatum peel exhibits high adsorption efficiency for Cu2+ ions, with a maximum adsorption capacity of 19.62 mg/g. The adsorption process was best described by the pseudo-second-order kinetic model and the nonlinear Langmuir isotherm model. The newly developed activated carbon exhibits a markedly higher adsorption efficiency compared to existing activated carbons, highlighting its innovative potential for adsorbing Cu2+ ions. Consequently, its use proves to be a cost-effective and sustainable solution for treating copper-contaminated industrial effluents. In fact, this research offers a dual benefit by providing a sustainable waste management solution for agricultural residues and an effective method for treating industrial effluents. Incorporating this activated carbon in post-copper plating rinsing water treatment ensures regulatory compliance and facilitates water reuse. This approach also supports copper recovery and reuse in new plating baths, promoting cyclic material circulation within the industry. [ABSTRACT FROM AUTHOR]

Copyright of Chemical Industry / Hemijska Industrija is the property of Association of Chemical Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

When olive mill wastewater is given directly to nature without being treated, natural waters become coloured, aquatic life is adversely affected, surface and underground waters are polluted, bad odours occur, and soil quality deteriorates. For these reasons, waste water is not allowed to be poured into soil and water without being discharged. This problem has become a problem that needs to be solved for the Mediterranean countries. With this study, acid cracking and chemical treatability studies achieved the conversion of the physicochemical pretreatment process of olive black water to an automation system. With the applied processes, removal efficiencies of 85% for Chemical Oxygen Demand, 99% for suspended solids, 97% for oil grease and 92% for phenol were obtained. Since the mixing processes of the tanks in the chemical additions are long, the heating chamber in the acid cracking process is designed larger than the tanks. Thus, when there is a black water density in the system, the heating tank in this system can be used as a heating and resting tank in sudden densities in this system. This waste separation process includes producing raw materials, protecting natural resources, and increasing sustainability. In particular, separating the phenol material and making it usable have been essential gains. [ABSTRACT FROM AUTHOR]

This article explores the use of microbial methods to remove heavy metals from industrial effluent in the pharmaceutical industry. The effluent contains metallic cations that can contaminate the soil and food chain. Traditional treatments for metal-containing waste have limitations, so researchers are investigating alternative biological methods involving bacteria and bio surfactants. The article also presents a study on the effects of microbial treated and untreated tannery effluent on the growth of green gram. The study concludes that bacteria are effective in removing heavy metals from pharmaceutical effluent. [Extracted from the article]

• Photodegradation efficiency of xylenes followed orders of VUV>UV>Xe and N 2 +O 2 >N 2. • Xylene degradation produced aromatics, alkanes and carbonyls via three processes. • Isomerized products dominantly contributed to OFP, SOAFP and non-cancer risk. • Photodecomposition product, benzene, showed highest occupational exposure risk. • OFP, SOAFP and risks of products reduced sharply comparing with degraded xylenes. Photodegradation technology has been widely applied in the purification of industrial aromatic hydrocarbons. However, whether this technology efficiently removes the pollutants to prevent secondary pollution and health risk is still unclear. Here, the photodegradation processes of three xylenes were compared under designed reaction atmospheres and light sources. Xe lamp showed poor photodegradation ability toward xylenes, no matter in N 2 or N 2 +O 2 system, while much higher photodegradation performance of xylenes were obtained under ultraviolet (UV) and vacuum ultraviolet (VUV) irradiation, especially in N 2 +O 2 +VUV system, where 97.9% of m-xylene, 99.0% of o-xylene or 87.5% of p-xylene with the initial concentration of 860 mg/m3 was removed within 240 min. The xylenes underwent three processes of photo-isomerization, photodecomposition and photo-oxidation to produce intermediates of aromatics, alkanes and carbonyls. Among them, the photo-isomerization products showed the highest concentration percentage (e.g., ≥50% in o-xylene system), confirming that photo-isomerization reaction was the dominated photodegradation process of xylenes. Moreover, these isomerized products not only contributed about 97% and 91% to the formation potential of O 3 (OFP) and secondary organic aerosols (SOAFP), but also displayed obvious non-carcinogenic risk, although one of photodecomposition product—benzene showed the highest occupational exposure risk. Therefore, the secondary pollution and health risks of photodegradation products of xylenes were non-ignorable, although the OFP, SOAFP and health risks of the generated products reduced at least 4.5 times in comparison with that of the degraded xylenes. The findings are helpful for the appropriate application of this technology in the purification of industrial organic waste gas. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanomaterials exhibit a wide range of diverse properties based on their specific geometry, which include nano-colloids, nanorods, nanowires and other 2D nanomaterials, etc. [[3]]. Due this heavy demand for nanomaterials, considerable efforts have been made to develop functional nanostructured materials using different types of physical and chemical methods, which are mainly categorized into top-down and bottom-up approaches [[23]]. Nanomaterials are constantly receiving recognition in a wide range of chemical, biomedical and engineering branches, and their applications in all the relevant fields are increasing rapidly [[9]]. Currently, nanotechnology has become an integral part of science and technology and has played a crucial role in the development of a variety of technological advancements in different industries [[1]]. [Extracted from the article]

The oxygen-rich acyl functionalized conjugated microporous polymers (AC-CMPs) exhibit great potential as an adsorbent material for efficient particulate matter (PM) capture and selective CO 2 separation. The AC-CMPs possess good stability due to the highly delocalized π-π conjugated porous skeleton connected by continuous covalent bonds. This structure also allows for the maintenance of adsorption capacity even under conditions of high humidity and temperature. The high polarity environment generated by the open oxygen atoms within the AC-CMPs framework, along with a high micro/mesopore ratio, enable it to achieve a CO 2 adsorption capacity of 2.07 mmol/g at 273 K and 1 bar. The application of AC-CMPs shows great potential in the fields of industrial waste gas purification and carbon capture. [Display omitted] • AC-CMPs were prepared by targeted anchoring of acyl functional groups in π-conjugated porous backbone. • The gas flow process of PM trapped by AC-CMPs was simulated using Fluent. • The morphology of the hollow nanotube improves the dispersion and mass transfer of gas flow. • AC-CMPs have good stability in humid and high temperature environments. • AC-CMPs exhibit good selectivity for CO 2 under realistic carbon capture conditions. Adsorption and separation technologies based on physical adsorbents have the advantages of simple operation, low heat of adsorption and easy regeneration. They have received much attention for the capture of CO 2 and PM from flue gases. However, the inherent "trade-off" between adsorption capacity and adsorption selectivity, as well as the high gas permeation resistance after powder processing and shaping, severely limit the prospects for industrial applications. Here, acyl functional groups were strategically introduced into polymer frameworks to successfully synthesize monolithic adsorbents (AC-CMPs) with a hierarchical pore structure for PM capture and CO 2 /N 2 selective adsorption. The three-dimensional network structure composed of aligned hollow nanotubes effectively enhances the dispersion and mass transfer of gas flow per unit volume. Based on the porous media, multiphase flow model and discrete phase model, the gas flow process of PM trapped by AC-CMPs was simulated using Fluent. The simulation dynamically revealed the relationship between permeability resistance and filtration efficiency. The highly delocalized π-π conjugated porous skeleton linked by continuous covalent bonds endowed AC-CMPs with good stability, which prevented them from degrading in humid and high-temperature environments, thus keeping the adsorption capacity unchanged. The high polarity environment generated by the open oxygen atoms within the AC-CMPs framework, along with a high micro/mesopore ratio, enable it to achieve a CO 2 adsorption capacity of 2.07 mmol/g at 273 K and 1 bar. Ideal adsorption solution theory calculations (IAST) and CO 2 /N 2 column breakthrough experiments confirmed the excellent CO 2 selectivity of AC-CMPs under realistic carbon capture conditions. [ABSTRACT FROM AUTHOR]

Purpose. Increasing oil recovery from reservoirs, reducing water content, and decreasing costs by pumping formation water effectively cleaned of suspended solids allows you to get a picture of the uniform distribution of water over the reservoir and, in general, the quality maintenance of reservoir pressure in productive reservoirs. Methodology. The study on water treatment issues for maintaining reservoir pressure at existing oil fields has a variety of approaches. Therefore, the methods of analysis, review, comparison, modeling, experiment were used in the work. The analysis method made it possible to divide the problems of approaches to the formation water preparation for its injection into the reservoir into many elements, which made it possible to learn their properties, connections and relationships. This method contributes to a more detailed structuring of the problem of water treatment. The analogy method uses the study of the technology of preparation of reservoir water with suspended solids. Based on the data, an effective technology was studied for treating formation water from suspended solids and injecting it into a productive formation. Findings. The experiments carried out reflect the high-quality water preparation using the developed new industrial sand-gravel filter made of granular materials with variable particle sizes in the vertical direction, taking into account the rational parameters of the column height of the filter working area. The regularities were studied and the process of formation water preparation without suspended solid particles was improved on the basis of the theoretical and experimental studies carried out on a special laboratory unit. The dependence of the reservoir permeability in the bottomhole zone of injection wells on the size of solid suspended particles in the injected water was determined, and rational filter parameters were established for preparing injected water without suspended solid particles into the reservoir using granular materials with a variable fraction and water supply from the bottom up. Originality. An effective technology for deep purification of formation water from suspended clay particles is proposed by using filters made of granular materials with a variable particle size. The technical result of the invention is to increase the efficiency of purification of industrial waste and industrial formation waters with suspended solids. Practical value. A new method for deep formation water treatment is proposed, which ensures the capture of suspended solids. The results of experiments on establishing the regularity of the process of formation water filtration with suspended clay particles through a porous medium with variable pore sizes and granular particles are presented. A recommendation has been developed for choosing rational parameters and operating modes of a new filter for formation water treatment. [ABSTRACT FROM AUTHOR]

Walnut is one of the major dry fruits in the world. The annual production is around 3.8 million tons. There is a significant amount of walnut shell that is generated. Walnut shell is extremely tough and its degradation is very slow. Due to the significant problem it poses to the environment, utilisation of the shell in synthesis of various economically useful products has gained importance. Carbon nanotubes have been extensively utilised in the purification of industrial waste, as electrical conductors and adsorption of gases. The synthesis of carbon nanotubes from agro-industrial waste has gained importance due to the environmental safety associated with such an approach. Though a large number of studies exist on synthesis of activated carbon from Walnut shell, there are no reports on synthesis of carbon nanotubes from walnut shells. In our study, we report the synthesis of carbon nanotubes from walnut shells by pyrolysis. The synthesised nanotubes were characterised by X-ray diffraction, Fourier-transform Infrared spectroscopy and scanning electron microscopy. The study shows that synthesised nanotubes are multi-walled and are of high purity which could be applicable for any of the downstream applications. [ABSTRACT FROM AUTHOR]

With the continuous increase of CO 2 concentration in the atmosphere, many environmental problems and natural disasters have been brought about, so CO 2 capture and utilization technology has received extensive attention. Metal-organic frameworks (MOFs) play an important role in the field of CO 2 capture due to their high specific surface area, diverse structures and modifiable functions. Herein, two MOFs were designed and synthesized by solvothermal synthesis: {[Cd 2 (dcpp)(H 2 O) 2 ]·DMF·2 H 2 O} n (1), {[Co 2 (dcpp)(bpy)(H 2 O) 4 ]·3.5 H 2 O} n (2) (H 4 dcpp = (3, 5- dicarboxyphenyl) pyridine, 2, 2′-bipyridine = bpy). MOFs 1 is 3D microporous network structure based on a binuclear cadmium unit and (dcpp)4- ligand. MOF 2 shows 1D lattice chain, which are linked each other by π···π stacking and hydrogen bonding interactions to form a 3D microporous network. TPD experiments show that there are both Lewis acid sites and Lewis base sites in 1–2, which have high catalytic activity for cycloaddition of epoxides and CO 2 under mild solvent-free conditions, and has good recyclability and recyclability. Interestingly, 1–2 showed excellent catalytic CO 2 conversion ability, and a strong application potential in the field of industrial waste gas purification. In addition, 1–2 can also be used as a highly efficient catalyst for the Knoevenagel reaction. The thermal filtration experiment has proved its heterogeneity. The cyclic experiments show that 1–2 is an efficient, recyclable and stable heterogeneous catalyst. Finally, the mechanism of CO 2 cycloaddition and Knoevenagel condensation catalyzed by 1–2 was discussed. [Display omitted] • MOFs 1–2 has good catalytic activity against carbon dioxide and epoxides, based on abundant Lewis acid-base active sites. • MOFs 1–2 also have good catalytic conversion effect in simulated flue system. • MOFs 1–2 can catalyze Knoevenagel condensation efficiently, and has good catalytic effect on benzaldehyde with different substituents. • MOFs 1–2 catalysts in the two catalytic reactions have good stability, recyclability and heterogeneity. [ABSTRACT FROM AUTHOR]

The chemisorption of sulfur(IV) oxide (SO2) from air by natural aqueous media containing iron (Fe) ions is a current area of research interest. At the same time, studies of SO2 absorption from gases with higher concentrations of SO2 and at high temperature by solutions containing Fe compounds are not enough to predict the purification process of industrial waste sulfur-containing gases. This study investigated SO2 absorption from a gas-air mixture by solutions containing Fe compounds under near-industrial conditions, viz., froth mode of bubbling, SO2 concentrations in the gas-air mixture about 0.21–4.05 g/m3 , and temperatures of 22°C–80°C. The experimental results showed that a rise in process temperature, SO2 concentration in the gas phase, the Fe species, and the initial pH of the absorbing solutions lead to an increase in the rate and efficiency of SO2 removal. It was determined that SO2 absorption by an Fe(II)- and Fe(III)-containing solution (initial pH=7.85) consists of three stages: (1) induction, (2) increase in absorption rate, and (3) decrease in absorption rate. Absorption of SO2 occurred efficiently only in the presence of Fe(OH)2 in the solution (the maximum rate of SO2 absorption reached 100%). Replacing Fe(OH)2 with Fe(OH)3 led to a decrease in the absorption rate by more than four times. This was caused by heterogeneous catalytic oxidation on the surface of Fe(OH)2 accompanied by the formation of peroxide compounds. The proposed mechanism of heterogeneous catalytic oxidation is discussed in reference to the available information in the literature. [ABSTRACT FROM AUTHOR]

The BiFeO 3 /V 2 O 5 has been successfully synthesized by simple annealing of BiFeO 3 nanoplates and V 2 O 5 nanoflower. The phase, structural, optical properties and chemical state of the BiFeO 3 , V 2 O 5 and different composition of BiFeO 3 /V 2 O 5 samples were comparatively characterized by various spectroscopic and microscopic techniques. The prepared catalyst exhibits unique photo catalytic and post-oxidation/reduction ability for removal of various (MB, Phenol, CV, RhB) water organic pollutants. Compared to pure BiFeO 3 and V 2 O 5 , the different Wt % of BiFeO 3 /V 2 O 5 composition exhibited higher photo catalytic activity. The fortunate BiFeO 3 /V 2 O 5 interface hybrid photo catalyst makes a significant impact in the enhancement of photo catalytic reaction. This remarkable efficiency could be ascribed to the synergistic effect between the V 2 O 5 petals and BiFeO 3 plates. The exceptional morphology, increased surface area, uniformity, less-agglomerated spreading could increase the ability of visible light response, which lead the improved electron transport ability and the higher charge separation. The enhanced rate of photo generated charge carriers separations were evinced by the EIS and PL spectrum measurements. The allowed radical trapping experiment divulge that the hole (h+), and super oxide radical (O 2 -) are the minimized effect in degradation, on the other hand hydroxyl radical (OH) is plays the foremost role and act as the active radicals in the catalytic organism. In relations of above investigation, a probable photo degradation mechanism of the as-synthesized photo catalyst is carefully explicated. This effort delivers an effective approach to design and fabricate the efficient photo catalyst through integrating of materials, which has a potential for industrial waste water purification. Image 1 • The BiFeO 3 /V 2 O 5 Nano heterostructure successfully prepared by effective methods. • The synthesized BiFeO 3 /V 2 O 5 material displayed a better physicochemical properties. • The BiFeO 3 /V 2 O 5 was thoroughly investigated for diverse organic pollutants removal. • The synergistic effect in BiFeO 3 /V 2 O 5 played important role in photo degradation. • A systematic investigation of photo catalytic removal mechanism is proposed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Machine Construction & Maintenance is the property of Institute for Sustainable Technologies - National Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The removal of heavy metals from mining waste leachate by spent coffee grounds has been investigated. In synthetic solutions, metal uptake was studied in batch adsorption experiments as a function of pH, contact time, initial metal concentration, adsorbent concentration, particle size, and the effect of co-ions (Na, K, Ca, Mg, Cu, Cd, Ni, Zn). Results showed that adsorption was significantly affected by pH, showing the highest affinity within a pH range of 5–7. Sorption of heavy metals reached equilibrium in 3 h. Removal percentages of metals ions increased with increasing dosage. Particle size did not have a significant influence on metal uptake. The adsorption of heavy metals was found to fit Langmuir and Freundlich isotherms. Maximum Zn, Cd and Ni uptake values were calculated as 10.22, 5.96 and 7.51 mg/g, respectively, using unwashed coffee grounds (UCG) as the adsorbent and 5.36, 4.28 and 4.37 mg/g when employing washed coffee grounds as the adsorbent. The presence of co-ions inhibited the uptake of heavy metals, divalent ions having a more negative effect than monovalent ions. The results obtained in the experiments with mining waste leachate showed that UCG is effective in removing heavy metals. [ABSTRACT FROM AUTHOR]

The paper investigates increasing permeate flux (%) of the disc membrane which can improve the quality of rubber industrial effluent of Tripura. Response surface methodology was used to optimize the independent influencing parameters to improve the permeate flux. The effect of different influencing parameters like operating pressure, membrane pore size, and inlet feed velocity on membrane permeate flux were studied to determine the optimum operating conditions within the predefined boundary. The experiments were pre-planned and designed according to central composite rotatable design, and second-order polynomial regression model was developed for regression and analysis of variance study. Results show the membrane has maximum permeate flux (%) when the operating pressure is 14.50 Pa, pore size is 0.20 μm, and inlet feed velocity is 2.10 m/s. The Pareto analysis in the study established that the inlet velocity was the most influential parameter in the model equation. [ABSTRACT FROM AUTHOR]

Consider n firms (agents) located at a river, indexed by 1,⋯,n from upstream to downstream. The pollution generated by these firms induce cleaning costs c1,⋯,cn, where ci is the cost for cleaning the water in region i (according to the local environmental standards). The corresponding cost allocation problem is highly interesting both in theory and practice. Among the most prominent allocation schemes are the so-called Local Responsibility and Upstream Equal Sharing. The first one allocates simply each local cost ci to the corresponding firm i. The second distributes each ci equally among firms 1,⋯,i. We propose and characterize a dynamic scheme which, given a particular order of arrival, allocates the current total cost among the firms that have arrived so far. The corresponding expected allocation (w.r.t. a random arrival order) turns out to be a convex combination of the two schemes above. [ABSTRACT FROM AUTHOR]

Abstract Industrial microbial waste (IMW) from amylase production using Aspergillus niger was characterized and utilized as novel adsorbent to remove two model cationic dyes (crystal violet, CV; methylene blue, MB) in their single and binary system. IMW was composed of organic Aspergillus niger biomass and inorganic perlite and diatomite, and thereby was regarded as a composite sorbent which was also characterized using FTIR, SEM, and XPS. The sorptive properties of IMW were studied in batch experiments by varying initial dye concentration, contact time, temperature, sorbent dosage, and NaCl concentration. The adsorption of CV and MB exhibited very similar trends in both single and binary dye solutions. Isotherms, kinetics, and thermodynamics were used to describe the sorption processes. The Langmuir model provided a good fit of the experimental data with the maximum monolayer adsorption (q m) of 175.4 mg/g and 92.6 mg/g for CV s and MB s , respectively in the single dye system. In the mixed dye solutions, the q m for CV m and MB m was reduced to 74.6 mg/g and 52.9 mg/g, respectively. Second-order kinetic model (R2 > 0.999) better explained the adsorption for the two dyes in single or mixed forms, suggesting chemical sorption nature of the process. The adsorption was dominated primarily by membrane diffusion and found to be endothermic and spontaneous. The IMW can thus be repurposed as a novel and promising cleaning agent for removal of organic pollutants from miscellaneous wastewaters. Graphical abstract DS b : dye solution (50 mg/L) before adsorption; DS a : dye solution after adsorption for 4 h (dye removal rate > 96%); IMW b : industrial microbial waste before adsorption; IMW cv : industrial microbial waste sorbed with CV after 4-h adsorption (q e = 23.9 mg/g); IMW mb : industrial microbial waste sorbed with MB after 4-h adsorption (q e = 25.0 mg/g); IMW mx : industrial microbial waste sorbed with CV and MB after 4-h adsorption (q e = 23.3 mg/g for CV and 24.8 mg/g for MB). Image [ABSTRACT FROM AUTHOR]

Abstract Urban Wastewater Treatment Plants (UWTPs) treating mixed urban sewage and industrial wastewater are among the major hotspots for the spread of Antibiotic Resistance Genes (ARGs) into the environment. This study addresses the impact of the wastewater origin on ARG dynamics in a full-scale UWTP (15,000 Population Equivalent, PE) by operating the plant with and without industrial wastewater. Composite samples (4 L) from different treatment points were characterized for their chemical composition, bacterial abundance and for the abundance of four resistance genes against tetracycline, sulfonamides, erythromycin, and quinolones (tet A, sul 2, erm B, and qnr S), and of the class 1 integrons (intI 1). Although the chemical composition of the outflow significantly differed when the plant operated with or without industrial wastewater, the system efficiency in the removal of bacterial cells, ARGs, and intI 1 was constant. The final disinfection by peracetic acid (PAA) did not affect the removal of ARGs, independently of the wastewater origin and the chemical characteristics of the inflows. Our results demonstrated that a well-functioning small size UWTP could treat a significant amount of industrial wastewater mixed in the urban sewage without affecting the overall ARGs and class 1 integrons released into the environment. Graphical abstract Unlabelled Image Highlights • The impact of industrial wastewaters on the ARGs removal in UWTPs is unclear. • A full scale UWTP was run with or without industrial wastewater for a week. • The origin of the wastewater strongly affects the chemical quality of a WWTP effluent. • Wastewater origin has a limited impact on microbiological and genetic variables. • PAA disinfection is not effective in the removal of ARGs. [ABSTRACT FROM AUTHOR]

As we all know that water is essential to all forms of life and makes up about 70% of the human body weight. Due to the direct link of water quality with human welfare, the quality of water is of vital concern. Industrialization plays major role in the development of a country's economy. However, these plants and industries generate hazardous by-products and discharge them directly or partially treated into the environment which contaminates the surface water, ground water and soil causing a great threat to the life of human beings, animal and plants. In the present investigation an attempt has been made to identify the potential of water hyacinth (Eichornia crassipus) and Duckweed (Lemna minor) for the treatment of industrial waste water generated from Dehradun industrial area using phytoremediation technology on the basis of different physicochemical parameters such as pH, EC, DO, ORP, Salinity, TDS, BOD, COD, Hardness and Temperature. Eichornia crassipus shows maximum decrease in pH, TDS and COD and Lemna minor shows maximum decrease in EC, ORP, Salinity, BOD and TH. In case of DO maximum decrease was observed in control experiment. During the assessment period Lemna minor was found highly efficient in comparison to Eichornia crassipus. Both water hyacinth (Eichornia crassipus) and Duckweed (Lemna minor) shows maximum removal between 1st to 5th day of treatment but the removal goes down as the experiment proceeds towards the end as the retarded growth of plants was observed due to toxicity of accumulated pollutants inside the palnts. [ABSTRACT FROM AUTHOR]

Abstract Textile dyeing effluent has been the focus of considerable research because of its adverse effects on aquatic biota. Here, we present the first comprehensive study of a combined permanganate and ozone (KMnO 4 O 3) technique to treat different kinds of textile dyeing wastewater. We investigated the effects of process parameters on TOC and COD removal and the toxicity of the wastewater after KMnO 4 O 3 treatment. The synergistic mechanism involved in the KMnO 4 O 3 process is also discussed. The results indicate that KMnO 4 O 3 treatment is efficient in treating many kinds of textile dyeing wastewater. The TOC, COD, and toxicity were reduced by approximately 70%, 80%, and 34.4–95.5%, respectively, using a KMnO 4 dosage of 1.5 mM, an O 3 dosage of 10 mg/L, a pH value of 7, and a reaction time of 30 min. Furthermore, biodegradability was increased to 0.33–0.68. The combined use of KMnO 4 and O 3 provided synergetic and complementary advantages. On the one hand, oxidation of pollutants on suspended solid surfaces and in the aqueous phase was enhanced by the stirring action of O 3 molecule bubbles. On the other hand, small molecular organic compounds and fine particles were coagulated by KMnO 4 and its intermediate oxidations. X-ray photoelectron spectroscopy results indicate that the valence state of manganese changed after KMnO 4 O 3 treatment, and the manganese intermediate catalysing O 3 process contributed to the removal of 20% of COD and 19% of TOC. It was therefore determined that the KMnO 4 O 3 treatment is a promising method for use in the treatment of textile dyeing wastewater. Graphical abstract Image Highlights • KMnO 4 -O 3 at neutral was more effective than KMnO 4 at acidic or O 3 at alkaline. • The toxicity was reduced and biodegradability was increased after KMnO 4 -O 3 process. • The stirring of O 3 and coagulating role of KMnO 4 provided synergetic effect. • MnO x catalysing O 3 contributed to 20% COD and 19% TOC removal. [ABSTRACT FROM AUTHOR]

Present research was designed to investigate heavy metal (HM) accumulation, distribution, relative tolerance and biochemical attributes of diverse 30 wheat genotypes on irrigation with textile (T2) and iron-steel industrial wastewater (T3) in pots in natural environmental conditions. The T3 wastewater was more polluted in terms of HM i.e. Ni, Cr, Mn, Fe, Pb and Zn than T2 wastewater. Relatively acidic pH and low organic matter of T3 recipient soils facilitated higher HM accumulation in corresponding wheat genotypes than T2 and control (T1). Significant genotypic variations in metal accumulation were recorded and pattern of accumulation was i.e. roots>stem>>grain. Tolerant, sensitive and intermediate performing wheat genotypes from T2 and T3 were identified using multivariate techniques. Tolerant genotypes exhibited efficient biochemical mechanisms (antioxidant enzymes and proline) to overcome HM stresses as compared to sensitive genotypes. Cultivation of tolerant wheat genotypes in soils receiving similar HM wastes can minimize their hazardous effects on plant physiology and plant produce. Enzymatic antioxidants i.e. SOD, POD, CAT and proline were identified as important biomarkers of heavy metals toxicity in tolerant and sensitive wheat genotypes. Tolerant genotypes can potentially contribute in regional and global food safety programs on breeding. [ABSTRACT FROM AUTHOR]

The use of industrial waste to synthesize materials of technological interest is a rational way to minimize or solve environmental pollution problems. This work reports the removal of chromium ions from tannery effluent using magnetic hybrid adsorbents synthesized from waste biomass: coconut mesocarp (HCN), sugar cane bagasse (HBS), sawdust (HS), and termite nest (HT). The presence of organic matter and the cobalt ferrite phase in the structures of the materials were confirmed by XRD and FTIR analyses. Removal assays performed at different pH values showed the effectiveness of the adsorbents for removal at the natural pH of the effluent (pH 4.75), with adsorption capacity exceeding 6.6 mg g−1 for all the hybrids studied. The adsorption processes showed fast kinetics, with the HS hybrid removing 5.1 mg g−1 of the chromium species present in the effluent in the first 5 min. The HS hybrid presented the highest removal capacity, 6.7 mg g−1, while HBS showed the lowest, 6.6 mg g−1. The removal at equilibrium showed the following increasing order of efficiency of the hybrids: HBS < HCN < HT ≈ HS. The HCN and HT adsorbent matrices saturated with chromium ions (HCNCr and HTCr) showed excellent catalytic performance in the reduction of 4-nitrophenol, with 99.9% conversion within 180-240 s. The other hybrids did not present catalytic activity. The materials showed high capacities for reuse in two successive reduction cycles. The findings highlight the effectiveness of an industrial symbiosis approach to the development of new technologically important materials. [ABSTRACT FROM AUTHOR]

The recycling of solid wastes is a major ecological goal. Although recycling is technologically feasible, reversing the flow of materials in the channels of distribution -- marketing trash through a "backward" channel -- presents a challenge. Existing backward channels are primitive, and financial incentives are inadequate. The consumer must be motivated to undergo a role change and become a producer -- the initiating force in the reverse distribution process. INSET: A New Business Competitor Abroad.... [ABSTRACT FROM AUTHOR]

Mass exchange network (MEN) synthesis is an important technique to ensure efficient purification of industrial waste gas sources and water streams. However, most existing models for MEN synthesis are not capable of dealing with multi-component problems and achieving optimal designs. In this study, an innovative process integration strategy based on a node-based vertical non-structural model (NV-NSM) is proposed. The developed strategy allows for a more random representation of process configuration and aids in handling both single- and multi-component problems. The NV-NSM arranges several groups of main nodes in the process streams and the sub-nodes in their branches and results in design configurations by connecting any two sub-nodes on the rich and lean streams at the same main node number. When dealing with multi-component synthesis, the number of tray column is directly optimized to balance the mass transfer needs of different components. As part of the current investigation, the random walk algorithm with compulsive evolution (RWCE) is established to realize the simultaneous optimization of multiple variables, including the mass transfer loads, the number of trays, the stream split ratios, and the flowrates of lean streams. Furthermore, the fine-search strategy based on the RWCE is applied to improve global and local optimization performance. Finally, the proposed method is applied to four MEN cases featuring different exchanger specifications and considering both single and multiple components. The implementation and analysis result in more optimal solutions compared to those published in the literature, demonstrating the feasibility and effectiveness of the proposed method in analyzing and evaluating different MEN problems, including multi-component ones. • A node-based vertical non-structural model is presented for mass exchange networks. • The proposed model is feasible for both single and multiple component problems. • Random walk algorithm with compulsive evolution is used to optimize the new model. • The proposed method can balance the mass transfer needs of different components. • Four cases with single and multiple component are solved with lower system costs. [ABSTRACT FROM AUTHOR]

Abstract This work proposes a technology for phosphonate removal from wastewater using magnetically separable microparticles modified with a tailored ZnFeZr-oxyhydroxide adsorbent material which proved to be highly efficient, reaching a maximum loading of ∼20 mg nitrilotrimethylphosphonic acid-P/g (215 μmol NTMP/g) at room temperature, pH 6 and 30 min contact time. The adsorption process at pH < 7 was fast, following the pseudo-second-order kinetics model. Furthermore, NTMP adsorption onto ZnFeZr-oxyhydroxide proved to be endothermic. At pH > pH pzc ≈7 (point of zero charge of the material) a drop in adsorption efficiency was observed for phosphate and for five different investigated phosphonates. Adsorption of NTMP could not be detected at pH > 8, however, the presence of more than 0.5 mM CaII improved significantly the adsorption efficiency. Successful reusability of the engineered particles was demonstrated throughout 30 loading cycles by changing the operational conditions (dose, pH) to optimize the performance. At optimal conditions, complete phosphonate removal was observed even after 30 cycles of particles' reuse in a synthetic NTMP-solution and DTPMP-rich membrane concentrate. In each cycle, phosphorus was desorbed and concentrated in a 2 M NaOH. Industrial phosphonate-containing wastewaters rich in calcium, e.g. membrane concentrates, proved to be especially suitable for treatment with the particles. Graphical abstract Image 1 Highlights • Phosphonates could be adsorbed >99% using ZnFeZr-oxyhydroxide @ magnetic particles. • Adsorption strongly depends on the pH and the point of zero charge of the material. • CaII significantly improved the adsorption with increasing concentration. • Successful reusability of the particles was demonstrated for 30 loading cycles. • Membrane concentrates are especially suitable for treatment with the particles. [ABSTRACT FROM AUTHOR]

Abstract In this work, water-based paint (WBP) wastewater was treated using a natural coagulant, Moringa oleifera aqueous extract (MOAE), fortified with Ca2+ (from nitrate and chloride salts). In order to improve the quality of the treated wastewater and render it suitable for disposal, an electrolytic flow process was associated with the wastewater treatment using a filter-press reactor with a boron doped diamond (BDD) electrode. The feasibility of the treatment was evidenced by the reuse of the treated wastewater in the production of a new paint (manufactured by the company supplying the raw wastewater), whose quality was compatible with the water used by the manufacturer. The best conditions for the coagulation-flocculation process involved the use of 80 mL of MOAE (50 g/L of MO and 0.125 mol/L of Ca2+) for every 1.0 L of wastewater at pH 6.5. The limiting current density (35 mA/cm2) and an electrolysis time of 90 min (charge passed of 3.68 A h/L) were used in the electrochemical treatment. Biotoxicity assays using the brine shrimp Artemia salina revealed that the mortality (in %) of microcrustaceans was reduced from 100% (raw wastewater) to only 11% at the end of the electrolysis process, in addition to eliminating the strong odor and 85% of the organic load. Moreover, microbiological tests showed that the number of mesophiles decreased by more than six orders of magnitude and there was no growth of thermotolerant coliforms (TC). Graphical abstract Image 1 Highlights • M. oleifera (biocoagulant) meets the quality control requirements for reuse proposal. • Calcium ions potentiate the coagulating effect of the protein contained in M. oleifera. • Reuse is only possible if Ca2+ ions (from a NO 3 − salt) are added into biocoagulant. • Electrochemical treatment wastewater is required for water discharge proposal. • The quality of the paints produced with recycled water was similar to the marketed. [ABSTRACT FROM AUTHOR]

In recent years, metallic nanoparticles (NPs) have been produced by biological methods using bacteria and have been used with remarkable environmental applications. This paper emphasizes the basic aspects of microbial synthesis of metallic nanoparticles, from the selection of the strain to the settings of reaction parameters. Mechanisms involved in the microbial production of NPs are also discussed, summarizing general findings and implications in the process. There is also a section dedicated to the identification of wastes as a source of precious metals and the production of metallic NPs from waste streams containing ionic metals to give a vision of the opportunities to implement microbial synthesis as a treatment–recovery technology. Environmental applications of biogenic NPs are reviewed in detail indicating that the implementation of these nanomaterials enable the achievement of higher removal efficiencies and greater extent of transformation of recalcitrant compounds in wastewater treatment systems. Under this scenario and based on the information reviewed concluding remarks and futures perspectives are enunciated. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Coagulation-flocculation has been proven as one of the effective processes in treating palm oil mill effluent (POME), which is a highly polluted wastewater generated from palm oil milling process. Two pairs of natural coagulant-flocculant were studied and evaluated: peanut-okra and wheat germ-okra. This research aims to optimize the operating parameters of the coagulation flocculation process in removing turbidity, total suspended solid and chemical oxygen demand (COD) from POME by using a central composite design in the Design Expert® software. Important parameters such as operating pH, coagulant and flocculant dosages were empirically determined using jar test experiment and optimized using response surface methodology module. Significant quadratic polynomial models were obtained via regression analyses (R2) for peanut-okra (0.9355, 0.9534 and 0.8586 for turbidity, total suspended solids and COD removal, respectively) and wheat germ-okra (0.9638, 0.9578 and 0.7691 for turbidity, total suspended solids and COD removal, respectively). The highest observed removal efficiencies of turbidity, total suspended solids and COD (92.5, 86.6 and 34.8%, respectively, for peanut-okra; 86.6, 87.5 and 43.6%, respectively, for wheat germ-okra) were obtained at optimum pH, coagulant and flocculant dosages (pH 11.6, 1000.1 mg/L and 135.5 mg/L, respectively, for peanut-okra; pH 12, 1170.5 mg/L and 100 mg/L, respectively, for wheat germ-okra). The coagulation flocculation performance of peanut-okra and wheat germ-okra were comparable to each other. Characterizations of the natural coagulant-flocculant, as well as the sludge produced, were performed using Fourier transform infrared, energy-dispersive X-ray spectroscopy and field emission scanning electron microscope. More than 98% of water was removed from POME sludge by using centrifuge and drying methods, indicating that a significant reduction in sludge volume was achieved. [ABSTRACT FROM AUTHOR]

Sugarcane and bioethanol production produces large amounts of bagasse fly ash and vinasse, which are solid and viscous liquid wastes, respectively. However, these wastes are often disposed into the environment without treatment, thus posing an environmental and public health risk. This study investigated the treatment of vinasse effluent in terms of reduction of chemical oxygen demand (COD) and acidity removal using sugarcane bagasse fly ash. A maximum COD removal efficiency of 72% was obtained using an effluent volume of 100 mL, contact time of 180 min, and shaking speed of 240 rpm. The adsorbent dose and particle sizes were 4.5 g and 90–125 μm, respectively. Furthermore, the potential application of bagasse fly ash as an adsorbent in a sand filtration bed was assessed using a column test. A maximum recovery of 68% was obtained at the 25-min interval. The adsorption data was found to fit the Freundlich model best ( K f  = 2.16 mg g −1 ; R 2  = 0.96), and the kinetics fit the pseudo-second order model (R 2  = 0.98). [ABSTRACT FROM AUTHOR]

Olive mill wastewater (OMW) was supplied to Scenedesmus sp. cultures to simultaneously achieve biomass production and wastewater biodegradation. Two OMW supply strategies were implemented to prevent the reduced growth performances that are attained, compared to photoautotrophic cultivation, when OMW is supplied at the beginning of cultivation (batch strategy). A fed-batch strategy including the gradual OMW supply yielded a biomass production equal to 0.86 g/L, while 1.4 g/L was attained by a two-stage strategy including OMW addition during nitrogen-starvation. OMW enhanced the carbohydrate accumulation (up to 44%) through the removal of OMW sugars (60–70%). About 55% OMW phenol removal was achieved by the fed-batch strategy when the phenol concentration was lower than 100 mg/L, and by the two-stage strategy when the heterotrophic stage lasted longer than 8–10 days. The illustrated results indicate that the OMW supply strategy can be purposefully tailored to regulate biomass production and OMW biodegradation. [ABSTRACT FROM AUTHOR]

Ferrate [Fe(VI)] is increasingly used for the treatment of several contaminants in drinking water and municipal/industrial waste water. Recent findings also show that Fe(VI) is a promising alternative for the treatment of gold mine effluents contaminated by cyanides (CN − ), thiocyanates (SCN − ), and ammonia nitrogen (NH 3 -N). However, the ferric [Fe(III)] salt used in Fe(VI) synthesis could affect this alternative’s efficiency and costs, as well as residual contaminants in the treated effluent. The objective of this study was to evaluate the influence of three Fe(III) salts on the performance of Fe(VI) in the treatment of gold mine effluents and the residual contaminants produced in the process. To do so, the performance of wet Fe(VI) synthesized with ferric nitrate [Fe(NO 3 ) 3 ], ferric chloride (FeCl 3 ), or ferric sulfate [Fe 2 (SO 4 ) 3 ] was evaluated for the treatment of a real gold mine effluent, with final adjustment of pH at ∼7. The results showed that for the effluents treated with Fe(VI) synthesized in the presence of Fe(NO 3 ) 3 , the final NO 3 − concentrations were 4 times higher relative to those in the treated effluents with Fe(VI) synthesized from either FeCl 3 or Fe 2 (SO 4 ) 3 . The use of Fe 2 (SO 4 ) 3 in the wet Fe(VI) preparation did not entail a significant increase of the final SO 4 2− concentrations, which were very similar to initial ones (1220 vs. 1012 mg/L). At the same time, Fe(VI) synthesized from Fe 2 (SO 4 ) 3 was the only one to remove the CN − and NH 3 -N almost totally (∼99%). Finally, the production yield of Fe(VI) with FeCl 3 was lower than Fe 2 (SO 4 ) 3 or Fe(NO 3 ) 3 (3400 vs. 5500 and 5635 mg/L, respectively). This low yield production of Fe(VI) from FeCl 3 entails more costly production costs. Thus, Fe 2 (SO 4 ) 3 is potentially the most appropriate Fe(III) salt source for Fe(VI) synthesis for use in the treatment of contaminated mine effluents. [ABSTRACT FROM AUTHOR]

The discharge of inadequately treated or untreated industrial wastewaters has greatly contributed to the release of contaminants into the environment, including toxic metals. Toxic metals are persistent and bioaccumulative, being their removal from wastewaters prior to release into water bodies of great concern. Literature reports the use of brown marine macroalgae for toxic metals removal from aqueous solutions as an economic and eco-friendly technique, even when applied to diluted solutions. Minor attention has been given to the application of this technique in the treatment of real wastewaters, which present a complex composition that can compromise the biosorption performance. Therefore, the main goal of this comprehensive review is to critically outline studies that: (i) applied brown marine macroalgae as natural cation exchanger for toxic metals removal from real and complex matrices; (ii) optimised the biosorption process in a fixed-bed column, which was further scaled-up to pilot plants. An overview of toxic metals sources, chemistry and toxicity, which are relevant aspects to understand and develop treatment techniques, is initially presented. The problem of water resources pollution by toxic metals and more specifically the participation of metal finishing industries in the environmental contamination are issues also covered. The current and potential decontamination methods are presented including a discussion of their advantages and drawbacks. The literature on biosorption was reviewed in detail, considering especially the ion exchange properties of cell wall constituents, such as alginate and fucoidan, and their role in metal sequestration. Besides that, a detailed description of biosorption process design, especially in continuous mode, and the application of mechanistic models is addressed. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Treatment of industrial effluent containing toxic pollutants was studied. • Pre-treatment by CWAO was performed at atm. pressure and mild temperature. • Effect of ceria as promoter on Pt/Al 2 O 3 catalyst for CWAO was investigated. • Toxicity and biodegradability of the effluent after CWAO treatment was studied. • Complete mineralization was obtained by integration of CWAO & biological process. Abstract The treatment of non-biodegradable industrial effluent containing toxic pyridine compounds by integration of catalytic wet air oxidation (CWAO) and biological processes has been studied. The CWAO experiments were performed using ceria promoted Pt/Al 2 O 3 catalyst. The catalyst was characterized by various techniques and the stability of the catalyst was studied. The research intended to achieve two main objectives: a) biodegradability enhancement of toxic industrial effluent by CWAO which is operated at mild conditions and b) complete mineralization of effluent obtained after CWAO treatment by biological processes. Therefore, the CWAO experiments were performed at atmospheric pressure and the effect of various operating parameters such as ceria loading, catalyst dosage and temperature on Chemical oxygen Demand (COD) removal of industrial effluent was optimized. The CWAO reaction followed a first order reaction kinetic model. The catalyst stability test was performed to determine its reusability and the catalyst was found active after 3 cycles run. The biodegradability of the industrial effluent was found to be improved from 0.07 to 0.56 and toxicity was completely removed after CWAO treatment. The effluent obtained after CWAO was further treated with biological aerobic treatment and a total COD removal of 98.4% was obtained after 10 days of aerobic treatment. [ABSTRACT FROM AUTHOR]

Industries such as mining operations are facing challenges of treating sulfur-containing wastewater such as acid mine drainage (AMD) generated in their plant. The aim of this work is to evaluate the use of a revolving algal biofilm (RAB) reactor to treat AMD with low pH (3.5–4) and high sulfate content (1–4 g/L). The RAB reactors resulted in sulfate removal efficiency up to 46% and removal rate up to 0.56 g/L-day, much higher than those obtained in suspension algal culture. The high-throughput sequencing revealed that the RAB reactor contained diverse cyanobacteria, green algae, diatoms, and acid reducing bacteria that contribute the sulfate removal through various mechanisms. The RAB reactors also showed a superior performance of COD, ammonia and phosphorus removal. Collectively, the study demonstrated that RAB-based process is an effective method to remove sulfate in wastewater with small footprint and can be potentially installed in municipal or industrial wastewater treatment facilities. [ABSTRACT FROM AUTHOR]

A series of composites of Mn-Fe-Ce/GO-x have been synthesized by a hydrothermal method. Their performance in simultaneously performing the catalytic oxidation of Hg0 and the selective catalytic reduction of nitrogen oxides (NOx) in the same temperature range were investigated. In order to investigate the physicochemical properties and surface reaction, basic tests, including Brunauer-Emmett-Teller (BET), XRD, scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) were selected. The results indicate that the active components deposited on graphene play an important role in the removal of mercury and NOx, with different valences. Especially, the catalyst of Mn-Fe-Ce/GO-20% possesses an excellent efficiency in the temperature range of 170 to 250 °C. Graphene has a huge specific surface area and good mechanical property; thus, the active components of the Mn-Fe-Ce catalyst can be highly dispersed on the surface of graphene oxide. In addition, the effects of O2, H2O, NO and SO2 on the removal efficiency of Hg0 were examined in flue gas. Furthermore, the regeneration experiments conducted by thermal methods proved to be promising methods. [ABSTRACT FROM AUTHOR]

Drainage canal sediments in an industrial park are generally dredged to landfill in Taiwan. The objective of this study was to evaluate feasibility employing the sediment as an adsorbent for removal of dye. The sediment contained approximately 10% of organic matter and little heavy metals. Infrared (IR) analysis revealed that carboxyl was the most important functional group for methylene blue (MB) sorption. Canal sediment could remove the most MB from water at pH 8.0 and this removal increased with increasing temperature. The MB sorption was well described by the Langmuir, Dubinin-Radushkevich, and Temkin sorption isotherms at 10 &°C, but it showed good compliance with Freundlich isotherm at 25 °C and 40 °C. The MB adsorption was a spontaneous and endothermic reaction; its maximum calculated adsorption capacity (Qm) was 56.0 mg g-1 at 10 °C by the Langmuir isotherm. The calculated values of enthalpy (ΔH°) and entropy (ΔS°) are 14.6 kJ mol-1 and 149.2 kJ mol-1, respectively. Only pseudo-second-order adsorption kinetic model successfully described the kinetics of MB onto the sediment at different operation parameters. Activation energy of MB adsorption calculated from Arrhenius equation was 16.434 kJ mol-1, indicating the binding between canal sediment and MB was a physical adsorption. [ABSTRACT FROM AUTHOR]

Forward osmosis (FO) is a potential membrane technology to treat wastewater energy efficiently with low fouling. In laboratory-scale experiments, six effluents from a dairy and an automobile production plant were tested to find out if FO is an applicable treatment technology. Permeate flux and reverse salt flux were determined in nine test series with three subsequent 5 h experiments each. In between, the membrane was cleaned with deionized water. Membrane performance tests before each experiment were used to monitor membrane performance and fouling. Samples were analysed and the T/M-value was introduced to indicate which substances caused fouling. Dairy cheese brine was a suitable DS. Here, permeate fluxes were 21.0 and 15.1 L/(m2·h). Automobile cooling tower water and wastewater from cathodic dip painting were also used as DS. However, permeate fluxes were below 1.1 L/(m2·h). The tested FS, reverse osmosis concentrate from dairy wastewater treatment, rinsing water and wastewater from automobile cathodic dip painting, as well as wastewater from automobile paint shop pre-treatment, showed good performance regarding the permeate flux of between 7.9 and 19.4 L/(m2·h). Membrane performance test showed that some of the effluents lead to permeate flux reduction due to fouling. Different cleaning-in-place methods were examined. Eventually, permeate flux was restored. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are highly toxic contaminants commonly dissolved in industrial wastewater. Therefore, treatment of VOC-containing wastewater requires a robust and rapid reaction because liquid VOCs can become volatile secondary pollutants. In this study, electro-oxidation with catalytic composite dimensionally stable anodes (DSAs)—a promising process for degrading organic pollutants—was applied to remove various VOCs (chloroform, benzene, toluene, and trichloroethylene). Excellent treatment efficiency of VOCs was demonstrated. To evaluate the VOC removal rate of each DSA, a titanium plate, a frequently used substratum, was coated with four different highly electrocatalytic composite materials (platinum group metals), Ir, Ir Pt, Ir Ru, and Ir Pd. Ir was used as a base catalyst to maintain the electrochemical stability of the anode. Current density and electrolyte concentration were evaluated over various ranges (20–45 mA/cm 2 and 0.01–0.15 mol/L as NaCl, respectively) to determine the optimum operating condition. Results indicated that chloroform was the most refractory VOC tested due to its robust chemical bond strength. Moreover, the optimum current density and electrolyte concentration were 25 mA/cm 2 and 0.05 M, respectively, representing the most cost-effective condition. Four DSAs were examined (Ir/Ti, Ir Pt/Ti, Ir Ru/Ti, and Ir Pd/Ti). The Ir Pd/Ti anode was the most suitable for treatment of VOCs presenting the highest chloroform removal performance of 78.8%, energy consumption of 0.38 kWh per unit mass (g) of oxidized chloroform, and the least volatilized fraction of 4.4%. Ir Pd/Ti was the most suitable anode material for VOC treatment because of its unique structure, high wettability, and high surface area. [ABSTRACT FROM AUTHOR]

Advanced oxidation processes (AOPs) are promising technologies to mineralize organic pollutants and reduce chemical oxygen demand (COD) from water effluents. Unfortunately, treatment of real industrial effluents is barely reported in literature and actual application is rare. One of the technology transfer limitations is associated to the identification of the most suitable stage for AOPs implementation in existing water treatment facilities of industry manufacturers. Here, we report a complete study where the most suitable stage for Fenton treatment implementation for a screw manufacture industry water treatment facility is identified. Actual wastewater effluent was collected, characterized and treated by means of Fluidized-bed Fenton (FBF) treatment to reduce COD levels. Fenton’s reagents feeding mode is evaluated to better understand influence on continuous flow operational FBF performance and efficiency. [ABSTRACT FROM AUTHOR]

Fish canning industry generates large amounts of liquid wastes, which are discarded, after proper treatment to remove the organic load. However, alternative treatment processes may also be designed in order to target the recovery of valuable compounds; with this procedure, these wastewaters are converted into liquid by-products, becoming an additional source of revenue for the company. This study evaluated green and economically sustainable methodologies for the extraction of ω3 lipids from fish canning liquid by-products. Lipids were extracted by processes combining physical and chemical parameters (conventional and pressurized extraction processes), as well as chemical and biological parameters. Furthermore, LCA was applied to evaluate the environmental performance and costs indicators for each process. Results indicated that extraction with high hydrostatic pressure provides the highest amounts of ω3 polyunsaturated fatty acids (3331,5 mg L −1 effluent), apart from presenting the lowest environmental impact and costs. The studied procedures allow to obtain alternative, sustainable and traceable sources of ω3 lipids for further applications in food, pharmaceutical and cosmetic industries. Additionally, such approach contributes towards the organic depuration of canning liquid effluents, therefore reducing the overall waste treatment costs. [ABSTRACT FROM AUTHOR]

Effluents from many industries are one of the major sources of water pollution and represent important environmental problems. Generally, paper recycling process generates large amounts of wastewater. Electrocoagulation (EC) is an evolving technology that has been effectively applied in the treatment of industrial wastewater containing various pollutants, such as textile wastewaters or chemical mechanical polishing wastewaters. This technique has a great ability to remove the pollutants from water due to its high efficiency, economically attractive and relatively lower sludge formation compared with other conventional processes such as biological, physical, chemical, adsorption and advanced oxidation processes. However, electrocoagulation (EC) process has been proposed as alternative to biological, physical and chemical methods due to its environmentally friendly and cheap to operate. This paper presents the experimental results obtained by applying the electrocoagulation method for removing the organic pollutants (COD) and total suspended solids (TSS) from wastewaters generated in the paper mill that use as raw materials recycled papers. [ABSTRACT FROM AUTHOR]

In this a, three-layered feedforward-backpropagation artificial neural network (BPANN) model was developed and employed to evaluate COD removal an upflow anaerobic sludge blanket (UASB) reactor treating industrial starch processing wastewater. At the end of UASB operation, microbial community characterization revealed satisfactory composition of microbes whereas morphology depicted rod-shaped archaea. pH, COD, NH 4 + , VFA, OLR and biogas yield were selected by principal component analysis and used as input variables. Whilst tangent sigmoid function ( tansig ) and linear function ( purelin ) were assigned as activation functions at the hidden-layer and output-layer, respectively, optimum BPANN architecture was achieved with Levenberg-Marquardt algorithm ( trainlm ) after eleven training algorithms had been tested. Based on performance indicators such the mean squared errors, fractional variance, index of agreement and coefficient of determination (R 2 ), the BPANN model demonstrated significant performance with R 2 reaching 87%. The study revealed that, control and optimization of an anaerobic digestion process with BPANN model was feasible. [ABSTRACT FROM AUTHOR]

This experiment aimed to decolorize Reactive Red 159 using a high potential of a consortium of purple nonsulfur bacteria (PNSB) with an application of response surface methodology through a central composite design in open system. The three factors of hydraulic retention time (HRT), sludge retention time (SRT) and dye concentration were applied to the design. The decolorization was operated in an anaerobic sequencing batch reactor until the system reached to a pseudosteady state for 30 cycles in each experiment. The optimal condition was 6,500 mg/L of Reactive Red 159 concentration with 20 days of SRT and 8 days of HRT, achieving dye effluent of 142.62 ± 5.35 mg/L, decolorization rate of 264.54 ± 7.13 mg/L/h and decolorization efficiency of 97.68 ± 0.74%. The results revealed that PNSB efficiently decolorized the high concentration of Reactive Red 159 and they were a high potential of microorganisms for dyes contaminated wastewater treatment. [ABSTRACT FROM AUTHOR]

New designs for improved hydraulic filters, devices, and installations for purification and neutralization of industrial sewage are considered. The basic tendencies in the development of designs for hydraulic filters, devices, and installations for sewage purification and neutralization are discussed. [ABSTRACT FROM AUTHOR]

In this study, polyethylenimine (PEI) modified Lagerstroemia speciosa leaves powder (PEI-LS) as low-cost and eco-friendly biosorbent was efficiently applied for gold recovery from acidic solution. Our experimental data show that PEI-LS is effective in complete recovery of gold at pH 1, compared to the raw L. speciosa leaves powder (raw LS) biomass. The adsorption kinetic results show gold adsorption reaches equilibrium in 6 h and follows a pseudo-second order kinetic. The adsorption isotherm data were best explained by Freundlich model and the monolayer adsorption capacity of PEI-LS for gold are in the range 286–313 mg/g. Thermodynamic parameters suggest that gold adsorption on PEI-LS was spontaneous and endothermic in nature. The developed PEI-LS was reusable up to 4 cycles with ∼98% gold recovery. Further, the calculated separation factor values suggest the PEI-LS shows high selectivity for low concentration of gold over the other co-existing metal ions in binary mixtures. Various instrumental characterization of raw LS and PEI-LS confirms the successful grafting of PEI on biomass surface. Surface analytical techniques like X-ray photoelectron spectroscopic (XPS) analysis confirms the adsorption-reduction mechanism of gold ions on PEI-LS leading to the formation of zero-valent gold on the biosorbent surface. The XPS was also used to characterize the PEI-LS surface functional groups (N1s) responsible for gold adsorption-reduction mechanism. The PEI-LS was successfully applied for quantitative gold recovery (≥95%) from an acidic solution of electronic scrap, gold refining sludge and wastewater. [ABSTRACT FROM AUTHOR]

The flocculation efficiency of a cationic polysaccharide with 1-(2-hydroxypropyl)-3-methyl imidazolium chloride groups attached to dextran (D40-MeIm36) was evaluated on synthetic wastewaters containing either inorganic particles (Zirconium silicate (kreutzonit), Kfeldspar, TiO 2 ) or organic ones (pesticides (Decis) and (Dithane M45)). The effect of polymer dose, medium pH, its composition and contaminant concentration on the separation efficacy was followed by UV–Vis spectroscopy measurements. The interactions between D40-MeIm36 and inorganic particles led to maximum removal efficiency (of around 95%), irrespective of the medium pH and composition. The negative values of the zeta potential, at the optimum polymer doses, point to charge patch as mechanism for the particles flocculation. A good efficiency of D40-MeIm36 in separation of pesticides has been noticed; the maximum removal percent slightly increased with increasing pesticide concentration, namely, from 85% at c (v/v) = 0.01% to 92% – 94% for c (v/v) = 0.02% and 0.04% for Decis and from around 85% at c = 0.1 g L −1 to 89% at c = 0.2 g L −1 for Dithane M45. A minimum residual pesticide absorbance of about 10% has been recorded for both pesticides, at the established medium pH. Zeta potential and particle aggregates size data plead for the charge neutralization as the dominant mechanism for the flocculation of pesticide particles. [ABSTRACT FROM AUTHOR]