Optimization of a cationic dye desorption from a loaded-lignocellulosic biomass: factorial design experiments and investigation of mechanisms

The sustainable management of loaded adsorbents with organic pollutants represents an important environmental challenge. The current research work investigates the regeneration process optimization of raw orange tree sawdust (ROS) loaded with methylene blue (MB) by using NaCl solutions as eluent. The MB desorption was assessed in static mode under different process variables, notably the desorbing NaCl solution’s pH and concentration and the MB-loaded biomass dose. A full factorial design composed of 24 experiments was employed to apprehend the statistical significance of each followed parameter. Experimental results showed that the maximum desorption yield was estimated to be about 82.4% for the following parameter’s values: aqueous pH $=$ 3, [NaCl] $=$ 0.2 M and MB-loaded-ROS dosage in the desorbing solution $=$ 1 g$\cdot$L$^{-1}$. The statistical study confirmed the good fit of the experimental data with the statistical model used as well as regression and adjusted regression coefficients of about 99.0% and 96.6%, respectively. Moreover, the ranking of the effect of each studied parameter in terms of standardized effect on the desorption efficiency of MB from ROS was assessed through ANOVA test. The desorption mechanisms involved were explored by using multiple analysis techniques. It appears that the MB molecules’ desorption from ROS’s particles is mainly driven by a counter chemisorption process based on cationic exchange with the sodium and hydronium ions present in the desorbing solutions

Enhancement of rhizocompetence in pathogenic bacteria removal of a constructed wetland system

Preprin

Optimization of a cationic dye desorption from a loaded-lignocellulosic biomass: factorial design experiments and investigation of mechanisms

The sustainable management of loaded adsorbents with organic pollutants represents an important environmental challenge. The current research work investigates the regeneration process optimization of raw orange tree sawdust (ROS) loaded with methylene blue (MB) by using NaCl solutions as eluent. The MB desorption was assessed in static mode under different process variables, notably the desorbing NaCl solution’s pH and concentration and the MB-loaded biomass dose. A full factorial design composed of 24 experiments was employed to apprehend the statistical significance of each followed parameter. Experimental results showed that the maximum desorption yield was estimated to be about 82.4% for the following parameter’s values: aqueous pH $=$ 3, [NaCl] $=$ 0.2 M and MB-loaded-ROS dosage in the desorbing solution $=$ 1 g$\cdot$L$^{-1}$. The statistical study confirmed the good fit of the experimental data with the statistical model used as well as regression and adjusted regression coefficients of about 99.0% and 96.6%, respectively. Moreover, the ranking of the effect of each studied parameter in terms of standardized effect on the desorption efficiency of MB from ROS was assessed through ANOVA test. The desorption mechanisms involved were explored by using multiple analysis techniques. It appears that the MB molecules’ desorption from ROS’s particles is mainly driven by a counter chemisorption process based on cationic exchange with the sodium and hydronium ions present in the desorbing solutions

Slaughterhouse Wastewater Treatment: A Review on Recycling and Reuse Possibilities

Slaughterhouses produce a large amount of wastewater, therefore, with respect to the increasing water scarcity, slaughterhouse wastewater (SWW) recycling seems to be a desirable goal. The emerging challenges and opportunities for recycling and reuse have been examined here. The selection of a suitable process for SWW recycling is dependent on the characteristics of the wastewater, the available technology, and the legal requirements. SWW recycling is not operated at a large scale up to date, due to local legal sanitary requirements as well as challenges in technical implementation. Since SWW recycling with single-stage technologies is unlikely, combined processes are examined and evaluated within the scope of this publication. The process combination of dissolved air flotation (DAF) followed by membrane bioreactor (MBR) and, finally, reverse osmosis (RO) as a polishing step seems to be particularly promising. In this way, wastewater treatment for process water reuse could be achieved in theory, as well as in comparable laboratory experiments. Furthermore, it was calculated via the methane production potential that the entire energy demand of wastewater treatment could be covered if the organic fraction of the wastewater was used for biogas production.DFG, 414044773, Open Access Publizieren 2021 - 2022 / Technische Universität Berli

Rapport II.9. Comportement électrochimique et analytique de la corrosion des crépines en acier ordinaire et galvanisé par les eaux de forage

Bousselmi Latifa, Ennabli Mohamed, Triki Ezzeddine. Rapport II.9. Comportement électrochimique et analytique de la corrosion des crépines en acier ordinaire et galvanisé par les eaux de forage. In: Les eaux souterraines et la gestion des eaux. Progrès - qualité - quantité. Vingt et unièmes journées de l'hydraulique. Sophia-Antipolis, 29-31 janvier 1991. Tome 2, 1991

The hydropolitical challenges of domestic water conservation: Palestine and Tunisia case studies

Southern Mediterranean area, particularly the Middle East and North Africa (MENA), has been facing social, economic, environmental and political challenges related to the water scarcity and quality. Within the European SWMED project, a socio-economic survey was conducted in Palestine and Tunisia, in order to explore the water conditions, and the social and economic situations of local families. The article illustrates the research design and implementation, as well as the main results that were used to select the appropriate sustainable water management solutions to respond to the hydropolitical issues. Due to the huge use of water in agriculture and the difficulty of reducing the water consumption in this sector, fostering tools for domestic water saving may be a winning strategy for facing water scarcity in MENA region.Fil: Anzera, Giuseppe. Università degli studi di Roma "La Sapienza"; ItaliaFil: Belotti, Francesca. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Università degli studi di Roma "La Sapienza"; ItaliaFil: Bousselmi, Latifa. Centre des Recherches et des Technologies des Eaux; TúnezFil: Rabi, Ayman. Palestinian Hydrology Group; Palestina (ANP

Role of SiOx interlayer in the electrochemical degradation of Amaranth dye using SS/PbO2 anodes

A novel SS (Stainless steel)/SiOx/PbO2 anode for dye removal in water electrolysis was studied. SiOx interlayer was deposited by plasma enhanced chemical vapor deposition (PECVD) in plasma fed with argon, oxygen and tetraethoxysilane (TEOS) in different ratios. Lead oxide was deposited by pulsed electrodeposition. Well-adherent and homogeneous SiOx film, characterized by high hydrophobicity, were deposited in oxygen rich plasma onto the SS substrate as confirmed by the morphological characterization performed by means of Field Emission Scanning Electron Microscopy (FESEM). The composition of PbO2 layer was investigated by X-ray diffractometry (XRD) and evidenced that β-PbO2 crystallites nucleation was promoted by the SiOx interlayer. Additionally, Electrochemical Impedance Spectroscopy (EIS) measurements were performed for assessing the electrochemical behaviour of the SS/SiOx/PbO2 anodes. Results confirmed that the increase in the presence of the β-PbO2 form, increases the conductivity of the PbO2 film. Finally, the anode, with SiOx interlayer deposited in oxygen rich plasma, showed the best efficiency in removing the azoic dye from aqueous solution in terms of COD and color remova