Taghreed Mohamed Zewail

Optimization of color removal from two types of anionic dyes by electrocoagulation/flotation in a batch agitated vessel

AbstractThe optimum conditions for the electrocoagulation/flotation of two types of anionic dyes (reactive Cibacron Red H-D dye and direct Sulphonil Yellow 5GL dye) have been investigated. The batch agitated vessel consisted of 45° pitched iron paddle anode and a horizontal iron disc cathode which was fixed at the bottom of the vessel. The performance of the vessel was expressed in terms of the percentage of color removal and power consumption calculations. Different parameters have been studied such as: electrolysis time, current density, NaCl concentration, initial dye concentration, initial solution pH, mixing speed (rpm), distance between electrodes, and different anode/cathode combinations. Results revealed that at optimum operating conditions using Fe/Fe electrode combination almost complete color removal of the two investigated dyes has been achieved. Economic studies reveal that removal of one kg of the reactive and direct dye requires 1.87 and 1.5 EGP, respectively. The treatment of real textile ...

Effect of crude oil on the rate of diffusion-controlled corrosion in pipelines under turbulent flow conditions

Abstract The present work aimed to investigate the effect of crude oil on the rate of diffusion-controlled corrosion of copper pipeline in acidified dichromate under fully developed flow. To achieve this goal, various parameters were investigated, such as crude oil percentage volume (%), flow physical properties, active height of the copper pipeline, flow velocity, and the presence of Triton X-100. The results of our study revealed that the rate of copper pipeline inner-wall corrosion increases with the increase of crude oil percentage volume and flow velocity. On the other hand, the active height of copper pipeline has no significant effect on the corrosion rate. In addition, the presence of crude oil and Triton has a synergistic effect on retarding the corrosion rate. The inhibition efficiency of Triton X-100 varied from 4.4% to 41.3% depending on its concentration and flow velocity. Polarization curves indicated that the corrosion kinetics is diffusion controlled in acidified dichromate and in the presence of crude oil and Triton X-100. However, the corrosion kinetics is mixed controlled in the presence of acidified dichromate and crude oil. Correlation of the present mass transfer data using dimensionless analysis led to the following dimensionless equation: Sh=0.58Re0.5Sc0.33, with the conditions 677<Sc<1490 and 3699<Re<30,874. The present work highlighted the practical importance of the present mass transfer correlation in the design and protection against corrosion of pipelines due to crude oil transportation.

Evaluation of Erosion Corrosion in Liquid–Solid and Liquid–Gas via Experimental Analysis Inside 90° Copper Elbow

Erosion–corrosion experiments of copper elbow were performed by acidified dichromate. Mass transfer coefficient inside 90° copper elbow has been investigated. The results showed that the mass transfer coefficient increases as solution velocity increases in both cases of one- and two-phase flow. The mass transfer coefficient can be related to the solution velocity in case one-phase flow by the following equations:

Liquid-Solid Mass Transfer Behavior of a Vertical Array of Closely Spaced Horizontal Tubes in Relation to Catalytic and Electrochemical Reactor Design

k \, \alpha \, v^{ 0. 4 4}\quad{\text{for\,Sc\,from\,678 to 845}}

Comparison Between Corrosion Behavior of Copper and Stainless Steel 90° Elbow and Failure Investigation of 90° Copper Elbow

kαv0.44for\,Sc\,from\,678 to 845

Investigation of color removal from methylene blue containing solutions by electrocoagulation/flotation in a batch‐agitated electrochemical reactor

k \, \alpha \, v^{ 0. 3}\quad{\text{for\,Sc\,from\,1040\,to\,1445}}