Lead removal from aqueous solutions by olive mill wastes derived biochar: Batch experiments and geochemical modelling.

In this study, lead removal from aqueous solutions using biochar derived from olive mill solid and liquid wastes has been investigated by applying batch experiments and geochemical modelling. The batch adsorption experiments included the assessment of several key parameters such as the contact time (kinetic), initial concentration (isotherm), pH, adsorbent dose, and the presence of competitive cations, whilst the geochemical modelling focused on the involved adsorption mechanisms using the PHREEQC code. The kinetic studies showed that lead adsorption is a relatively fast process, where intraparticle diffusion is the rate-limiting step.

Characterization of the biofilm grown on 304L stainless steel in urban wastewaters: extracellular polymeric substances (EPS) and bacterial consortia.

Characterization of the biofilm growing on stainless steel (SS) in untreated (UTUWW) and treated (TUWW) urban wastewaters was performed. In both media, the first phase of biofilm growth was aerobic, when the genera and (iron oxidizing bacteria [IOB]) and the genera , , and (sulfur oxidizing bacteria [SOB]) were identified. In the second phase, established after immersion for 7 days, the high amount of EPS inhibited the access of oxygen and promoted the growth of anaerobic bacteria, which were the genus (iron-reducing bacterium [IRB]) and the genera , , and (sulfate-reducing bacteria [SRB]).

Application of olive mill waste-based biochars in agriculture: Impact on soil properties, enzymatic activities and tomato growth.

The olive oil industry is an important economic sector in Mediterranean countries. However, oil production is unfortunately accompanied by the generation of huge amounts of olive mill solid wastes (OMSW) and olive mill wastewater (OMWW). In the present study, a strategy is proposed for converting these olive mill wastes into biochar through pyrolysis, for their later use as an organic amendment in agriculture.

Optimization of hybrid treatment of olive mill wastewaters through impregnation onto raw cypress sawdust and electrocoagulation.

This research investigation proposes a new method for sustainable olive mill wastewater (OMW) treatment and handling. It is based on the combination of its impregnation onto raw cypress sawdust (RCS) followed by electrocoagulation. The retention of OMW compounds onto various RCS doses show an important decrease of its chemical oxygen demand (COD) and its main cation and anion content.

Coupling anodic oxidation, biosorption and alternating current as alternative for wastewater purification.

Anodic oxidation process is considered as an effective solution for the treatment of refractory effluents. Its performance is strongly depending on the stability of the anodes used during the process. For this reason, we aim to enhance the stability of the SS/PbO anodes electrodeposited by pulsed current while studying their performance for the anodic oxidation of methylene blue and industrial textile wastewater.

Use of alternating current for colored water purification by anodic oxidation with SS/PbO and Pb/PbO electrodes.

This paper suggests a new alternative for the acceleration of dye removal by adopting alternating current instead of direct current in the treatment of methylene blue solutions and industrials effluents, using anodic oxidation on Pb/PbO and stainless steel (SS)/PbO anodes. A comparative study of the influence of electrolyte support (NaCl, NaNO, and NaSO) on the anodic oxidation performance and the anode stability was performed. The best results were obtained in presence of NaCl where the color removal percentage reached about 80.

Highly efficient modified lead oxide electrode using a spin coating/electrodeposition mode on titanium for electrochemical treatment of pharmaceutical pollutant.

In this study, Ti/TiO/PbO anodes consisting of a PbO coating growth on the TiO interlayer deposited on titanium substrates were prepared combining different deposition technics: electrochemical method using anodization (Anod), electrodeposition (EL), and sol gel spin coating (SG). Different kinds of anodes have been tested for the removal of ampicillin, a pharmaceutical pollutant, from water. The structure and the surface morphology of the prepared multiple coatings were characterized by scanning electron microscopy and Energy-Dispersive X-ray spectroscopy respectively.

Effect of coating method on the structure and properties of a novel PbO anode for electrochemical oxidation of Amaranth dye.

This study deals with the electrochemical degradation of Amaranth in aqueous solution by means of stainless steel (SS) electrodes coated with a SiO interlayer deposited by Plasma Enhanced Chemical Vapour Deposition and a modified PbO top layer deposited by continuous galvanostatic electrodeposition. The morphological characterization of the PbO top-layer performed by Field Emission Scanning Electron Microscope put in evidence that the SiO, interlayer allows obtaining a more integrated PbO/SS electrode with a very homogeneous PbO film. The composition of the lead oxide layer was investigated by X-ray Diffractometry, showing that the β-PbO/α-PbO ratio in the top layer deposited on the SiO film was four times higher respect to the one deposited directly on the stainless steel surface.

Comparative study of electrochemical hybrid systems for the treatment of real wastewaters from agri-food activities.

Agri-food wastewaters are characterized by high contents of hardly biodegradable organics and large amounts of inorganics especially nitrogen and phosphorus. The present work investigates the efficiency of two electrochemical treatment processes, namely electrochemical oxidation/reduction (EOR), electrocoagulation (EC) and their combination for the treatment of two types of effluents collected from poultry slaughterhouse (SHWW) and dairy (DWW) industries. The optimization of these treatment systems in terms of pollutant performance removal and energy cost were carried out.

Optimization of a cationic dye removal by a chemically modified agriculture by-product using response surface methodology: biomasses characterization and adsorption properties.

The present study investigates the alkaline modification of raw orange tree sawdust (ROS) for an optimal removal of methylene blue (MB), as a cationic dye model, from synthetic solutions. The effects of operating parameters, namely, sodium hydroxide (NaOH) concentrations, ROS doses in NaOH solutions, stirring times, and initial MB concentrations on dye removal efficiency, were followed in batch mode. The process optimization was performed through the response surface methodology approach (RSM) by using Minitab17 software.

Nitrate and carbon matter removals from real effluents using Si/BDD electrode.

This work investigated the electrochemical treatment of four real effluents which were municipal wastewater (MWW), human urine (HU), river water (Wadi), and slaughterhouse wastewater (SHWW). The treatment was performed on a Boron-Doped Diamond (BDD) as anode/cathode material with an applied current density of 35.7 mA cm and without any reagent addition.

Anodic oxidation of textile wastewaters on boron-doped diamond electrodes.

The objective of this study is to investigate the potential application of the anodic oxidation (AO) on two electrolytic cells (monopolar (Cell 1) and bipolar (Cell 2)) containing boron-doped diamond electrodes on the treatment of real textile effluents to study the reuse possibility of treated wastewater in the textile industry process. AO is applied in the flocculation coagulation pretreatment of both upstream (BH) and downstream (BS) effluents. The chemical oxygen demand (COD) results show that the final COD removal obtained for the BH effluent in the case of Cell 1 and Cell 2 is 800 and 150 mg O₂L⁻¹ after 5 and 6 h of electrolysis, respectively.

Evaluation of the efficiency of monopolar and bipolar BDD electrodes for electrochemical oxidation of anthraquinone textile synthetic effluent for reuse.

The efficiency of the electrochemical degradation of synthetic wastewater containing an anthraquinone dye has been comparatively studied in two electrolytic cells with a synthetic boron-doped diamond (Si/BDD) as an anode. The first is an individual cell (Cell 1) with monopolar electrode BDD and the second (Cell 2) has two bipolar electrodes BDD self-polarized. The bulk electrolysis was performed at the same initial operating conditions in order to quantify the influence of the initial pH and current density on dye discoloration and global mineralization removal.