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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]

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 inhibitory action of Schinus molle L. essential oil was investigated for the corrosion of carbon steel in 1 M hydrochloric acid solution using weight loss, polarization curves, and electrochemical impedance spectroscopy. The inhibition efficiency has increased with the increase of the inhibitor concentration, reaching a value of up to 70% at 2 g/L. [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]