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The objective of this research was to study the capacity of a new biosorbent from Acacia saligna leaf powder (ASLP) to remove methylene blue (MB) under varying operating conditions: initial concentration of the dye, the mass of biosorbent, adsorption time, pH, temperature and ionic strength. ASLP surface morphology, structural, and thermal properties were investigated by scanning electron microscopy, Fourier-transform infrared spectroscopy and thermogravimetric analysis, respectively. The study showed the significant role of cellulose, hemicellulose, and lignin, which are rich in functional groups such as -OH, -COOH, and -NH2, in the adsorption mechanism, enabling the effective binding of MB molecules. The Langmuir isotherm model was found to be the most suitable model for describing the experimental data, exhibiting a high coefficient of determination (R2 = 0.993). At room temperature, the maximum adsorption capacity achieved was 71.43 mg·g-1. The pseudo-second-order model (R2 = 1) provided a better description of the adsorption process of MB by ASLP compared to the pseudo-first-order model (R2 = 0.86). This observation can be attributed to the formation of a monolayer on the external surface of ASLP. The thermodynamic analysis indicated that the adsorption process was spontaneous, exothermic. The potential for regenerating and reusing the adsorbent was also investigated. The study findings highlight that A. saligna leaf powder is a cost-effective biosorbent that is readily accessible and adheres with the principles of green chemistry for the efficient removal of methylene blue from wastewater. [ABSTRACT FROM AUTHOR]

Biodegradable poly(butylene succinate) (PBS)/Alfa fiber biocomposites were prepared through the compression molding method. Scanning electron microscopy images were acquired to assess the effects of reinforcement and homogenization of mixtures and to determine the characteristics of the microstructure. The rheological properties, melting, and crystallization behavior of neat PBS and its biocomposites were investigated. Regarding the thermal properties, it was observed that the presence of Alfa fibers facilitates the crystallization of the PBS matrix, which suggests that Alfa cellulose fiber acts as a nucleating agent. The rheological analysis suggests that the biocomposites show a better dynamic behavior with the addition of Alfa fibers. Indeed, the incorporation of fibers increased the complex modulus and complex viscosity of the composites. Also, increasing the percentage of fibers in the matrix induces percolation, the shift and change in the slope of Cole–Cole curve of the PBS/Alfa fiber composite compared to that of neat PBS indicate that the PBS microstructure has changed with the addition of fibers. Moreover, the improvement of biocomposites properties is believed to be largely attributable to the homogeneous dispersion of the Alfa fibers within the polymer matrix and also to the strong interfacial interactions between the two constituents. [ABSTRACT FROM AUTHOR]

Nano spinel of cobalt ferrite CoFe2O4 (NCF) has been synthesized by Sol–gel auto-combustion method and used as an adsorbent to remove Acid Green AG25 dye from aqueous solution. The NCF was investigated by XRD, Rietveld refinement, SEM coupled with EDX, VSM, FTIR and pH of the zero-point charge pHzpc. The efficiency of the treatment was evaluated according to the characteristic parameters influencing the adsorption process: adsorbent dose, contact time, initial dye concentration, initial solution pH and temperature. The adsorption of AG25 followed pseudo-second order kinetic model. The equilibrium adsorption data fit to the Langmuir isotherm with a maximum capacity of 8.71 mg g−1. Thermodynamic data revealed that the process was exothermic, spontaneous and a physisorption nature. Through the established adsorption process and magnetization measurements, a mechanism was proposed to highlight the idea that the nano spinel of cobalt ferrite material has both magnetic and electronic characteristics. NCF is an efficient adsorbent, low cost, easily synthesized and environmental friendly for removal AG25 from aqueous solution.Highlights: Adsorption of AG25 dye by nanoferrite CoFe2O4 Synthèse by sol–gel auto-combustion mechanism study Combination between results of adsorption process and the proved magnetic properties CoFe2O4 material has both magnetic and electronic characteristics which can be beneficial for water pollution control [ABSTRACT FROM AUTHOR]

The management of household wastes is becoming a major preoccupation for local and national authorities in Algeria. A number of laws and regulations have been adopted since 2001. Human and material resources have been deployed in order to provide an appropriate solution. The district of Oran produces 1700 tons/day of municipal solid waste (MSW) and there management was limited to collecting and transporting to wild dumpsites. It has been counted 21 dumpsites over 163 hectares. To eradicate these dumpsites, 03 sanitary landfills (S.L) have been built to improve the management of household wastes. Indeed, there are practically no more dumpsites but no improvement has been registered at the level of two (S.L) under exploitation at present for several reasons (non qualified staff, lack of staff, insufficient material, absence of transfer center, decaying transport means, no valorization, and no optimization of neither collecting nor transporting. Our goal in this work is to propose efficient waste management, for assistance in decision making, for improving the exploitation of S.L and concrete proposition of valorization channels based on the 3R-VE principle (reduction of wastes at source, reuse, recycling, valorization and elimination). For this purpose, we have determined the main elements and parameters related to these wastes (stratum, ratio, physical composition, GHG produced by the landfill, services for collecting transporting, financing, staff, material...). The first results show that the ratios changed from 0.68 kg/capita/day in 2013 to 0.75 kg/capita/day in 2016. The recoverable fraction representing 48.7% of the total composition of wastes has increased during the last decade. But they shall remain insufficient valorization. The organic matter which represents more than 60-65% of household wastes in Algeria and in developing countries it has decreased to 52.3%. This is explained by weak modification of food habits. A financial study by valorization channel (composting, recycling and reuse) is proposed in this work. [ABSTRACT FROM AUTHOR]

The plasma–chemical degradation of Forafac 1110, a perfluorinated non-ionic surfactant, in aqueous solutions was investigated using TiO2 catalysts. The considered plasma was the gliding arc in humid air, which results from an electric discharge at atmospheric pressure and quasi-ambient temperature. Two titanium dioxide powders were used and their synergistic effects on the Forafac degradation were compared. The results were discussed through the evolution of the pH, the conductivity, the fluoride ions concentration released in solutions, the surfactant concentration remaining after treatment and the chemical oxygen demand (COD) measurement. The combination of the plasma–chemical treatment with heterogeneous catalysis through the use of TiO2 accelerated the Forafac degradation, since only 60min was sufficient to remove 96% instead of 360min needed in the absence of TiO2. The use of anatase and rutile under the trade-name of Rhodia TiO2 and Merck TiO2, respectively, led to different results, because Rhodia TiO2 has proven to be more efficient. It would seem that the crystalline phase as well as the crystallite size, explain the efficiency of anatase. The advantage of the plasma-catalysis is due to the fact that there is a significant production of the OH• radicals not only generated by the gliding arc discharge but also by TiO2. [Copyright &y& Elsevier]

This study deals with the pollution of the greatest river in Algeria, and, therefore, 180 sediment samples from the Cheliff River from three industrial areas in Tiaret, Relizane and Chief were analyzed. The concentration of heavy metals was determined by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). The results show that the sediment samples were highly polluted, particularly near Chlef and Relizane cities, with Cd (global mean: 5.48±0.27 mg Kg-1 dry weight), Pb (384±19), Zn (1264±63), Cu (442±22) and Cr (399±20). These results clearly exceed the ERL values recommended by US EPA. Due to natural dilution and diffusion, the level of contamination decreases near Tiaret. A comparison with the data of different sites throughout the world, the background values (Shale) and sediment quality guidelines was estab- lished. This study reveals that river sediments of Cheliff River are highly contaminated by five heavy metals: Cd, Pb, Zn, Cu and Cr. [ABSTRACT FROM AUTHOR]

The title synthesis starts from heteroarenes and furnishes the products in two or three steps following Pd-catalyzed desulfitative arylation and direct arylations using aryl bromides sequence. [ABSTRACT FROM AUTHOR]

Abstract: A new prototype of plate Dielectric Barrier Discharge (DBDplate) has been developed to treat liquid film falling by gravity. This approach is more pragmatic to extrapolate the technique at the pilot and industrial scale. Two modes of plasma process were adopted: (i) DBDplate alone and (ii) DBDplate coupled with TiO2 (CDBDplate). The addition of an optimized amount of TiO2 to the dye solution increased the discoloration rate from 11% to 96% for 220kJL−1 of energy density. For the same energy density, without photo-catalyst, no mineralization has been noticed. However, in its presence, the concentration of Total Organic Carbon (TOC) has decreased by 80%. In this work, plasma process has been carried out in a single cycle of treatment to reduce the energy needed to generate the plasma. The addition of TiO2 has intensified the DBDplate-plasma process. [Copyright &y& Elsevier]