Chemical Engineering / Kimya Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/14

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  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Insights Into Sustainability of Engineered Carbonaceous Material-Based Technologies for Advanced Cyanide Removal From Wastewater
    (Elsevier, 2023) Yoon, Yeojoon; Khataee, Alireza; Gören, Ayşegül Yağmur; Recepoğlu, Yaşar Kemal
    Cyanide (CN) is a serious concern in industrial and goldmine wastewater. Strict regula-tory standards have been established by various agencies due to the detrimental effects that CN has on human health. Therefore, before discharge to water bodies or land, it is essential to create a sus-tainable model for the safe removal of CN. Carbon-based materials are well known for their adsorption and oxidation features, which can be conducive to CN removal. This paper reviews the relevant literature on the application of modified and unmodified carbon-based materials to CN removal in water; these materials include activated carbon (AC), graphene, graphene oxide (GO), and carbon nanotubes (CNTs). Moreover, CN removal mechanisms and photocatalytic removal of CN are comprehensively discussed, with a particular emphasis on modifying carbon-based materials. It has been observed that adding various elements to carbon-based materials improves their surface area, functional groups, CN adsorption capacity, and pore volume. Impacts of operational parameters, isotherm models, kinetics, and types of carbon-based materials are also outlined. This study provides insight into the real-scale applicability of carbon-based materials for CN removal from waters. Moreover, this review indicates that essential work on CN removal using carbon-based materials is still needed. Future research should focus on developing modified carbon-based materials to encourage multidisciplinary research. The most crucial gap in the literature is that the studies have been performed on a lab scale. Therefore, further pilot and real-scale applica-tions should be conducted. Overall, the cost assessment, environmental effects, and human health risks of carbon-based materials should be studied in future research to achieve a realistic perspective on applicability on an industrial scale.(c) 2023 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).
  • Article
    Citation - WoS: 14
    Citation - Scopus: 12
    Photocatalytic Hydrogen Energy Evolution From Sugar Beet Wastewater
    (Wiley-VCH Verlag, 2021) Orak, Ceren; Yüksel, Aslı
    Hydrogen is a clean, environmentally friendly, storable, and sustainable green energy source as well as a potential fuel. It could be produced from various biomass, wastewater, or other sources by different processes. In this study, hydrogen was evolved from sucrose model solution and real sugar beet wastewater by photocatalytic oxidation using a perovskite catalyst under solar light irradiation. In this context, firstly, the graphene supported LaFeO3 (GLFO) was synthesized and then, a characterization study shows that GLFO is successfully synthesized. To optimize the reaction parameters (pH, catalyst loading, and initial hydrogen peroxide concentration), an experimental matrix was created using the Box Behnken model. Whereas the highest hydrogen evolution from sucrose model solution was observed as 3520 μmol/gcat, the highest hydrogen evolution from sugar beet wastewater was obtained as 7035 μmol/gcat. The highest TOC removal (99.73 %) from sugar beet wastewater was also achieved at the same reaction conditions.
  • Article
    Citation - WoS: 21
    Citation - Scopus: 21
    Graphene-Supported Lafeo3 for Photocatalytic Hydrogen Energy Production
    (Wiley, 2021) Orak, Ceren; Yüksel, Aslı
    Hydrogen is a green, environmentally benign and sustainable energy source with no harmful combustion products to fulfil the increasing energy demand. Photocatalytic oxidation has various advantageous to produce hydrogen from different sources such as wastewater, alcohol solutions using different types of catalysts. Sucrose solution was chosen as a model solution to evolve hydrogen using LFO and GLFO catalysts under solar light irradiation, and graphene was used as a catalyst support to enhance the amount of produced hydrogen amount. A characterization study, which consists of SEM-EDX, BET, XRD, PL, TEM, XPS and FT-IR analyses, was carried out. A full factorial design was created via Minitab 18 to analyse the factors affecting the produced hydrogen amount, which are pH, catalyst loading, H2O2 concentration and graphene content statistically. Based on the results, graphene content is an important parameter and pH and H2O2 concentration have a synergetic effect over hydrogen production. Additionally, the effects of calcination temperature, pH, H2O2 concentration and catalyst loading over produced gases were investigated. The best promising result was obtained as 3388 mu mol/g(cat) at the following reaction conditions: 7.5 of pH, 0.1 g L-1 catalyst loading (GLFO, which is calcined at 700 degrees C) and using 15 mM H2O2 under solar light irradiation. Novelty Statement Hydrogen is produced from sucrose solution with low cost process requiring no special equipment, high pressure or temperature. First study that uses perovskite catalysts for the production of hydrogen from sucrose solution by photo-Fenton like oxidation GLFO is a promising photocatalyst for H-2 production by solar-Fenton like oxidation with the highest H-2 evaluation at 3388.34 mu mol/g(cat).