The Combined Effect of Bubble and Photo Catalysis Technology in BTEX Removal from Produced Water

Among the several ways used in wastewater treatment, the photocatalysis process is a more novel and alternative process that is increasingly employed in recent years. This work aims to improve the performance of the photocatalyst process by using air bubbles in removing the BTEX from produced water as an indicator of process efficiency. The study also shows the effect of influencing factors (pH and residence time) on the photocatalysis process. The study was done in a rectangular column with dimensions of 200 mm width, 30 mm depth, and 1500 mm height. Commercial titanium oxide (TiO2) coated on a plate by the varnish was used as a source of the photocatalyst. The experiment was carried out under different values of gas flow rate (0-3 L/min) to evaluate its effect on the photocatalyst process, the effect of other variables of pH (3-11), and irradiation time (30-120) min was also studied. A new method of the coating was adopted by using an alumina plate with varnish as an adhesive. The characteristics results show that the coated plate has hydrophilic properties and that there is no significant change in the crystal structure of the TiO2 nanoparticles and the varnish before and after 60 h of the photocatalytic process, indicating that the plate is still effective after 60 h usage under different conditions. The results also show that the introduction of air bubbles enhances the removal efficiency of BTEX significantly and the best removal effectiveness of BTEX was 93% when pH = 5 after 90 min and 90% when pH = 3 after 120 min. The removal rate also reached 86% when pH = 7 after 120 min all at a flow rate of 3 L/min. The percentage of removal decreased at pH = 9 and 11, reaching 64% and 50%, respectively after 120 min and a flow rate of 3 L/min. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Catalytic-Level Identification of Prepared Pt/HY, Pt-Zn/HY, and Pt-Rh/HY Nanocatalysts on the Reforming Reactions of N-Heptane

The operation of reforming catalysts in a fixed bed reactor undergoes a high level of interaction between the operating parameters and the reaction mechanism. Understanding such an interaction reduces the catalyst deactivation rate. In the present work, three kinds of nanocatalysts (i.e., Pt/HY, Pt-Zn/HY, and Pt-Rh/HY) were synthesized. The catalysts’ performances were evaluated for n-heptane reactions in the fixed bed reactor. The operating conditions applied were the following: 1 bar pressure, WHSV of 4, hydrogen/n-heptane ratio of 4, and the reaction temperatures of 425, 450, 475, 500, and 525 °C. The optimal reaction temperature for all three types of nanocatalysts to produce high-quality isomers and aromatic hydrocarbons was 500 °C. Accordingly, the nanocatalyst Pt-Zn/HY provided the highest catalytic selectivity for the desired hydrocarbons. Moreover, the Pt-Zn/HY-nanocatalyst showed more resistance against catalyst deactivation in comparison with the other two types of nanocatalysts (Pt/HY and Pt-Rh/HY). This work offers more understanding for the application of nanocatalysts in the reforming process in petroleum refineries with high performance and economic feasibility