Mohamed Kheireddine Aroua

Optimisation of Reactive Black 5 dye removal by electrocoagulation process using response surface methodology

In this work, a regression model obtained from response surface methodology (RSM) was proposed for the electrocoagulation (EC) treatment of textile wastewater. The Reactive Black 5 dye (RB5) was used as a model dye to evaluate the performance of the model design. The effect of initial solution pH, applied current and treatment time on RB5 removal was investigated. The total number of experiments designed by RSM amounted to 27 runs, including three repeated experimental runs at the central point. The accuracy of the model was evaluated by the F-test, coefficient of determination (R2), adjusted R2 and standard deviation. The optimum conditions for RB5 removal were as follows: initial pH of 6.63, current of 0.075 A, electrolyte dose of 0.11 g/L and EC time of 50.3 min. The predicted RB5 removal was 83.3% and the percentage error between experimental and predicted results was only 3-5%. The obtained data confirm that the proposed model can be used for accurate prediction of RB5 removal. The value of the zeta potential increased with treatment time, and the X-ray diffraction pattern shows that iron complexes were found in the sludge.

Reactivity of carbon black diamond electrode during the electro-oxidation of Remazol Brilliant Blue R

This article reports for the first time, the reactivity of Carbon Black Diamond (CBD) electrode using cyclic voltammetry and electrochemical impedance techniques in 0.25 M H2SO4 solution containing 0.5 mM K4Fe(CN)6. Three CBD electrodes with different content of carbon black 5% (5CBD), 10% (10CBD), and 20% (20CBD) were used in this study. The reactions of the CBD electrodes were quasi-reversible while the 5CBD electrode had the best activity compared to 10CBD and 20CBD electrodes. The anodic oxidation behavior of Remazol Brilliant Blue R (RBBR) was investigated by using cyclic voltammetry and electrochemical impedance techniques on the 5CBD electrode in different pH solutions. The results indicated that the RBBR oxidized at 1.3 V, and the electro-oxidation process was more active in the low pH solution. Furthermore, the removal rate of RBBR on 5CBD attained 99.5% after 4 hours of the electro-oxidation process.

Pyrolysis of plastic waste for liquid fuel production as prospective energy resource

The worldwide plastic generation expanded over years because of the variety applications of plastics in numerous sectors that caused the accumulation of plastic waste in the landfill. The growing of plastics demand definitely affected the petroleum resources availability as non-renewable fossil fuel since plastics were the petroleum-based material. A few options that have been considered for plastic waste management were recycling and energy recovery technique. Nevertheless, several obstacles of recycling technique such as the needs of sorting process that was labour intensive and water pollution that lessened the process sustainability. As a result, the plastic waste conversion into energy was developed through innovation advancement and extensive research. Since plastics were part of petroleum, the oil produced through the pyrolysis process was said to have high calorific value that could be used as an alternative fuel. This paper reviewed the thermal and catalytic degradation of plastics through pyrolysis process and the key factors that affected the final end product, for instance, oil, gaseous and char. Additionally, the liquid fuel properties and a discussion on several perspectives regarding the optimization of the liquid oil yield for every plastic were also included in this paper.

Optimization study on preparation of amine functionalized sea mango (cerbera odollam) activated carbon for Carbon Dioxide (CO2) adsorption

ABSTRACT Activated carbon derived from sea mango (cerbera odollam), SMAC, was developed from phosphoric acid (H3PO4) activation. Box-Behnken Design (BBD) was employed to optimize the surface area of the SMAC. The tested factors were acid concentration (40 to 60%), carbonization temperature (400 to 600°C) and activation time (1 to 3 h). The optimized parameters were 53.75% H3PO4 concentration, 519.8°C of carbonization temperature and 2.3 h of activation time, which resulted in 857.93 m2/g of BET surface area. The performance of CO2 adsorption was investigated for modified and virgin SMAC. The impregnations of SMACs were done with different amines (AMP, PZ and MEA) to improve its natural adsorption ability and promote nitrogen functional group onto carbon surface with impregnation mass ratio of 2:5 (amine: activated carbon). The effects of adsorption parameters such as activated carbon properties, type of amine used, gas flow rate and adsorbent dosage on breakthrough curves and adsorption bed capacity were evaluated. Reduction in BET surface area indicates that the amine-based chemicals were successfully attached on carbon surface and thus blocked most of the pores on the SMAC particles. The modified surface of SMAC with AMP amine showed the best performance in CO2 adsorption and regeneration with adsorption bed capacity of 23.05 mgCO2/g sorbent. Successful CO2 adsorption via modified surface of SMAC suggested that it is viable to use sea mango as alternative precursor for activated carbon preparation and in application such as CO2 capture.