Investigation of photocatalytic removal and photonic efficiency of maxilon blue dye GRL in the presence of TiO2 nanoparticles

TiO₂ nanoparticles have been synthesized by solvent-free hydrothermal process. TiO₂ nanoparticles were annealed at 500°C for enhancing the characterization and the photocatalytic activity. The synthesized TiO₂ was characterized by x-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), BET, and diffuse reflectance spectroscopy (UV-DR) techniques to study the morphology and structural configuration. The effects of different parameters such as the initial dye concentration, catalyst concentration, pH of the solution, light intensity, and reactive oxygen species (ROS) on relative photonic efficiencies and photocatalytic degradation kinetics of GRL were investigated, and the degradation of GRL follows pseudo-first order kinetics according to the Langmuir–Hinshelwood model. The ROS studies indicate that hydroxyl radicals and holes are the predominant reactive species within the same step, contributing up to 92.64%, hydroxyl radicals participate for about 55%, and holes share for about 37.64% in the photocatalytic degradation of GRL.     

A PVDF transducer for low-frequency acceleration measurements

A unique acceleration transducer, using piezoelectric PVDF, has been developed for low-frequency vibration monitoring. The paper develops the theoretical model for this low-cost, robust sensor. The theoretical model is validated using experimental results from laboratory tests. The sensor was also installed in an underground potash mine alongside a commercial geophone for a three-month in-mine test producing results that show a close correspondence between the two transducers.     

Electrochemical treatment of chemical oxygen demand in produced water using flow‐by porous graphite electrode

Produced water is the largest wastewater stream generated in the oil and gas industries. In this study, experiments were carried out using a bench‐scale electrochemical cell using flow‐by porous graphite electrode, for oxidation of organic matter in produced water which was collected from natural gas processing field (real sample). The effect of anodic current density and influent feed flow rate on chemical oxygen demand (COD) removal efficiency, and energy consumption were investigated. The maximum removal efficiency of 66.52% was obtained for a flow rate of 50 mL/min, current density of 1.41 mA/cm² and pH of 7.3 for an influent COD of 2845 mg O₂/L. The energy consumption at these conditions was 2.12 kWh/kg_COD.     

Softening of tap water via calcium removal using sphagnum peat moss sorbent by batch and flow-through approaches

ABSTRACT

The Gaza Strip experiences a water crisis of persistent qualitative and quantitative deterioration in regard to groundwater. There is a low recharging rate of the aquifer because of the low seasonal rainfall, the fast expansion of the urban area, and the high seawater intrusion along the narrow coastal Gaza Strip. Thus, the extremely hard water reduces the performance of the reverse osmosis desalination household units and causes membrane fouling. Sphagnum peat for removal of calcium from water was investigated applying batch and flow-through approaches. Fast calcium removal was demonstrated.