Search

Polluted river water treatment utilizes a mix of physical, chemical, and biological processes and activities. Conventional systems, including coagulation, flocculation, sedimentation, filtration, and disinfection, have several limitations. Hence, the Membrane Photocatalytic Reactor (MPR) is one of the most promising methods for polluted river water treatment. ZnO-Kaolin nanoparticles served as great photocatalysts for MPR performance. This study focuses on the pilot-scale hybrid MPR treatment of polluted river water under different light intensities (100, 125, and 225 watts) and irradiation times (20, 30, and 40 minutes). The treated water quality analysis is based on the Environmental Quality Act 1974 (EQA 1974). The kinetic rate was also investigated using pseudo-first-order and pseudo-second-order models. It was found that 225 watts and 30 minutes were the optimum values. The pilot scale hybrid MPR proved to fit well with the pseudo-second-order kinetic models, suggesting that the degradation follows a chemisorption mechanism. In conclusion, we believe the hybrid MPR pilot-scale system will enhance efficiency in cleaning dirty river water, all while meeting the standards of the EQA 1974.

Zinc oxide (ZnO) nanoparticles have received great attention due to their advantages. Several improvements on the morphology of ZnO have been widely studied to solve the problem of agglomeration and surface-active sites. To date, there are limited studies involving the effect of flower-like ZnO in the application of thiophene desulfurization via photocatalysis process. Thus, this study focuses on the performance of different flower-like ZnO for synthetic thiophene desulfurization. Eight ZnO photocatalyst species were synthesised and categorized into two groups, namely flower-like ZnO and non-flower-like ZnO. The physical properties of all the ZnO morphologies were analysed. Moreover, their performances for desulfurization of synthetic thiophene were evaluated. From the findings, flower-like ZnO flakes showed the highest performance in synthetic thiophene desulfurization (30%). Higher pH (pH 11) and turbidity reduction (32%) of the permeate indicated the higher generation of hydroxyl radicals causing higher desulfurization of thiophene. From the kinetic study, all ZnO morphologies were applicable with pseudo-second-order models due to higher linear regression (R2 ) values. The highest concentration equilibrium, Ce value for flower-like ZnO flakes (909.09 mg/g) confirmed greater desulfurization of thiophene. Moreover, it was found that pH 7 in the presence of 0.05 g/L flower-like ZnO flakes for 90 minutes of irradiation were the best conditions and yield the highest desulfurization of 300 ppm synthetic thiophene (30%) due to the highest generation of hydroxyl radical. It is expected that this integrated approach could bring forward other initiative methods in overcoming the problems in petroleum industry related to desulfurization of sulphur-containing compounds.

Dye wastewater is the major environmental issue of the textile and printing industries besides other minor issues like solid waste, health and safety. The use of synthetic chemical dyes in various manufacturing industrial process has increased considerably over the past decades, resulting in the release of dye-containing industrial effluents into aquatic ecosystem and soil [1]. Wastewater from printing and dyeing industries is frequently rich in color, containing residues of toxic chemicals, reactive dyes and requires proper treatment before all the effluent release into environment [2]. There are more than 8000 chemical products associated with all the dyeing, printing and finishing process listed in the color index, including some of the structural diverse of dyes, such as basic, acidic, reactive, disperse, azo, diazo, anthraquinone based and metal-complex dyes [1]. Therefore, these wastes must be genuine treated before it discharge to environment in order to comply with the environmental protection for the receiving water.