Browsing by Author "Genel, Yasar"

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Catalytic Effect of Metal Powder and Mcm-41/Metal Catalysts on the Pyrolysis of Cellulose
(Wiley, 2024) Genel, Salih; Durak, Halil; Genel, Yasar
This study investigates the effect of support catalysts on the pyrolysis process of cellulose by comparing it with metal powder catalysts. MCM-41, MCM-41/Al, MCM-41/Fe, Al, and Fe metal powders were employed as catalysts, and the pyrolysis temperature was set at 350, 450, and 550?. The MCM-41 group catalysts were characterized using XRD, SEM-EDX, and SEM-EDS techniques. GC-MS and elemental analysis methods were used to analyze the liquid products. The results indicate that different catalysts can affect the energy value and product variety of cellulose pyrolysis. Specifically, Al and Fe powder catalysts yielded higher liquid product yields compared to MCM-41 group catalysts. The MCM-41 group catalysts mainly produced monoaromatic compounds, while Al and Fe powder catalysts were more effective at producing aliphatic compounds. These findings suggest that the selection of catalysts can have a significant impact on the outcome of cellulose pyrolysis.
Effect of Process Parameters on Supercritical Liquefaction of Xanthium Strumarium for Bio-Oil Production
(Elsevier, 2016) Genel, Yasar; Durak, Halil; Aysu, Tevfik; Genel, Ilyas
Supercritical liquefaction process is used for producing energy from biomass. The common reaction conditions for supercritical liquefaction process are the 240-380 degrees C temperature range and 5-20 MPa pressure values range. Xanthium strumarium liquefaction experiments were performed in a cylindrical reactor (75 mL) in organic solvents (acetone, ethanol, methanol) under supercritical conditions with (zinc oxide, calcium hydroxide) and without catalyst at the temperatures of 250, 275 and 300 degrees C. The produced liquids at 300 degrees C in liquefaction were analyzed and characterized by Elemental, GC-MS and FT-IR. 36, 37 and 50 different types of compounds were identified by GC-MS obtained in acetone, ethanol and methanol respectively. The liquid product efficiency has been obtained at 300 degrees C in acetone with zinc oxide catalyst (74.80%). The highest HHV value has been calculated as 32.16 MJ/kg with calcium hydroxide catalyst in acetone. (C) 2016 Elsevier B.V. All rights reserved.
Facile Oxygen-Enriched Hierarchical Porous Carbon Particles Based on Biomass Wastes for Improving the Adsorption of Malachite Green From Aqueous Solutions
(Elsevier, 2025) Genel, Yasar; Genel, Ilyas; Saka, Cafer
The abundance of active groups and the surface areas of adsorbents used for the removal of contaminants such as dyes are very important for the effective adsorption process. For this purpose, the high surface area-activated carbon was obtained by activation of agricultural waste chestnut shells as carbon precursor(CSAC) with sodium hydroxide in the first stage of this study. In the second stage, the doping of oxygen atoms with nitric acid was carried out to further improve the surface properties of this activated carbon (O-doped CSAC). The obtained oxygen-rich activated carbon sample was used as an adsorbent to remove a cationic dye malachite green (MG). EDS, SEM, XRD, FTIR and nitrogen adsorption analyses were used for the characterisation of these activated carbon samples. FTIR, elemental analysis and EDS analyses showed a significant increase in the amount of oxygen groups on the surface. The BET surface area obtained for CSAC had a high surface area of 1548 m(2)/g. Kinetic, thermodynamic and isotherm parameters for the adsorption of MG with O-doped CSAC were determined. The qe values obtained for MG adsorption with O-doped CSAC showed an adsorption efficiency of about 90 %. An adsorption capacity of 284.6 mg g(-1) was obtained at 298 K with the Langmuir isotherm. The adsorption mechanism of MG with O-doped CSAC was also investigated.
Facile Preparation of Sulfonated Carbon Particles With Pomegranate Peels as Adsorbent for Enhanced Methylene Blue Adsorption From Aqueous Solutions
(Springer Heidelberg, 2024) Genel, Yasar; Genel, Ilyas; Saka, Cafer
In this study, in the first stage, activated carbon (AC) is produced from pomegranate peels, which are commonly found in Turkey, by pyrolysis after impregnation with NaOH (PPAC). In the second stage, the surface properties of the obtained PPAC sample are further improved by the sulfonation modification process with sulphuric acid (PPAC-S) for selective MB adsorption. For the characterization of the obtained samples, XRD, FTIR, SEM, nitrogen adsorption/desorption and EDS analyses were performed. Additionally, the zero charge points (pHzpc) of these samples were also determined. The isotherm, kinetic, and thermodynamic properties of the MB adsorption process with PPAC-S were examined. The qe values obtained for MB adsorption with PPAC and PPAC-S samples were found to be 98.79 mg/g and 199.18 mg/g, respectively. There is an increase of 100% in MB adsorption with the sulfonated PPAC adsorbent. Maximum adsorption capacity values of MB with the Langmuir model at temperatures of 298, 308, and 318 degrees C were 212.7, 216.9, and 245.1 mg/g, respectively. Additionally, the mechanism of MB adsorption onto PPAC-S was also attempted to be elucidated.
Facile Synthesis of Mesoporous Activated Carbons Based on Ash Tree for Methylene Blue Adsorption: Mechanism, Kinetics, Isotherm, and Thermodynamic Studies
(Taylor & Francis inc, 2023) Genel, Yasar; Genel, Ilyas; Saka, Cafer
Activated carbons(AC) were synthesized as a result of chemical activation with ZnCl2, NaOH, H3PO4, and H3BO3 from the ash tree(AH), which is abundant in Turkey and the world. It was investigated that the obtained ACs could be used as effective adsorbents for the removal of methylene blue(MB) from the aqueous solution. SEM, EDX, BET, FTIR, and CHNS elemental analyses were used for the characterization of raw and ACs. The results show that carbonaceous materials contain both mesoporous and active functional groups. The maximum adsorption capacities obtained as a result of chemical activation of ZnCl2 (AH-ZnCl2) and NaOH (AH-NaOH) with the best surface area values were determined as 334 mg g(-1) and 364 mg g(-1), respectively. The adsorption mechanism was evaluated with pseudo-first-order and pseudo-second-order kinetic models. It can be concluded that ACs prepared from ash wood are quite ideal when compared with different adsorbents in the literature for removing methylene blue from aqueous solutions.
The Formation of Mathematical Model for Cacl2 Derived From The Reaction of Ulexite and Hydrochloric Acid by Using Full Factorial Desing Method
(Gazi Univ, 2013) Durak, Halil; Genel, Yasar; Bashirov, Novruz; Kerimov, Genber
One of the significant boron compounds which are common substance in nature is ulexite. Ulexite is a sodium calcium boron hydrate, its chemical formula is Na(2)O(2)CaO5B(2)O(3)16H(2)O, and it is thick with in Turkey. Lots of products are derived from boron minerals. One of them is boric acid. CaCl2 is used in many fields and this compound can be obtained by different processes. The aim of this study is producing CaCl2 by forming mathematical model for CaCl2 composing in the wake of the interaction of ulexite with hydrochloric acid solution. In the study, full factorial desing method has been used. Some of the parameters used in the process have been pegged, and the others have been regarded as variables. The pegged parameters are particle size, reaction time and stirring speed. Hydrochloric acid concentration, temperature and solid to liquid ratio have been regarded as variable factors in formation of mathematical model. The mathematical model of three-parameter full factorial desing mehtod and the mathematical model of the process have initially been assessed in dimensionless coordinate system, then the available values in the model have been computed by Student criteria, the validity of the formed model has been controlled by Fisher criteria. Henceforwards, the current model of the process has been formed in real coordinate system.
Heavy Metal Removal From Aqueous Solution by Activated Bentonite
(Parlar Scientific Publications (p S P), 2012) Genel, Yasar; Ceylan, Hasan; Saltabas, Omer
Bentonite was found to have adsorption capacity for Pb(II), Cr(III), Zn(II) and Co(II). Towards this aim, batch adsorption experiments were carried out and the effects of various parameters (solution pH, dose of bentonite loading, contact time, temperature, and initial metal concentration) on this removal process have been investigated. Adsorption was decreased with increasing temperature for all studied metals. The Langmuir and Freundlich adsorption models were used for mathematical description of the adsorption equilibrium. Equilibrium data was fitted to the Langmuir model in the concentrations of 10-100 mg L-1 at 293 and 313 K. Based on the Langmuir isotherm plots, the maximum adsorption capacity value was calculated to be 30.40 mg g(-1) for Cr(III), 30.27 mg g(-1) for Pb(II), 29.94 mg g(-1) for Zn(II), and 29.85 mg g(-1) for Co(II), at 293 K. Various thermodynamic parameters, such as Delta G degrees, Delta H degrees, and Delta S degrees, were evaluated with results indicating that this system was an exothermic spontaneous reaction and kinetically suited to pseudo-second order model. Adsorption ability of bentonite decreased in the order of Cr(III) > Pb(II) > Zn(II) > Co(II), and its adsorption capacity in the order of ZnCl2 activation > NaOH activation > H2SO4 activation > native bentonite.
Hydrothermal Conversion of Biomass (Xanthium Strumarium) To Energetic Materials and Comparison With Other Thermochemical Methods
(Elsevier, 2018) Durak, Halil; Genel, Yasar
In the present study, the biomass was converted into liquid and solid residues by using hydrothermal liquefaction method at 250, 300 and 350 degrees C with (FeCl3, NaOH) and without catalyst. The resultant products were examined using GC-MS, FT-IR, H-1 NMR, SEM, and elemental analysis methods. According to the performed analyses, the highest liquid product yield (total bio-oil) was found to be 38.08% at 300 degrees C by using FeCl3 as catalyst. In the experiments carried out at 350 degrees C, the highest HHV value was found to be 32.35 MJ kg(-1) by using NaOH catalyst. The energy values of products obtained at the end of experiments were compared to the values obtained from pyrolysis and supercritical liquefaction method, and it was determined that the liquid products having higher level of energy value were achieved by using hydrothermal liquefaction method.
Hydrothermal Liquefaction of Biomass With Molybdenum, Aluminum, Cobalt Metal Powder Catalysts and Evaluation of Wastewater by Fungus Cultivation
(Pergamon-elsevier Science Ltd, 2023) Genel, Salih; Durak, Halil; Durak, Emre Demirer; Gunes, Hasret; Genel, Yasar
In this study, the Ammi visnaga plant was liquefied in the presence of Mo, Al and Co metal powder catalysts and without catalyst. Liquefaction trials were carried out at 225, 250, 275 and 300 degrees C reaction temperatures and reaction times of 0, 15, 30 and 45 min. The highest liquid product yield was determined as 42.31% in the experiment without catalyst and 39.42% with Mo catalyst at 300 degrees C. GC-MS, XRD, TOC, SEM-EDX and Elemental analysis methods were used to characterization of solid and liquid product. The highest energy values were determined as 25.34 MJ/kg for light oil and 29.69 MJ/kg for heavy oil with Co catalyst. In order to investigate the agricultural application potential, the effects of the wastewater obtained at the end of the trials on Tricho-derma harzianum, Clonostachys rose and Rhizoctonia solani fungi were investigated. It was determined the bioagent fungi developed and pathogen growth was inhibited.
Mathematical Model Formation of the Process of Deriving Boric Acid From Ulexite Mineral by Full Factorial Design Method
(Gazi Univ, 2013) Durak, Halil; Genel, Yasar; Bashirov, Novruz; Kerimov, Genber
Ulexite is a sodium calcium boron hydrate used in producing compounds, its chemical formula is Na2O2CaO5B2O3.16H2O, and it superabounds in Turkey. One of the significant boron compounds derived from boron minerals is boric acid. The aim of this study is producing boric acid in the wake of interaction of ulexite with hydrochloric acid solution, and offering an alternative process to producing boric acid by forming the mathematical model of this processing. Full factorial design method has been used in the study. Some of the parameters used in the process have been made steady, and the others have been accepted as variable factor in formation of mathematical model. Invariant parameters are granule size, reaction time and stirring speed. Hydrochloric acid concentration has been accepted as temperature and solid to liquid ratio variable factors for the formation of mathematical model. Primarily, the mathematical model of the process and three-parameter full factorial desing have been evaluated in the measureless coordinate system, then the values in the model has been assessed by Student criteria, and the validity of the originated model has been controlled by Fisher criteria. Henceforwards the current model of the process has been formed in the real coordinate system.
Optimization of the Dissolution of Tincal Ore in Phosphoric Acid Solutions at High Temperatures
(Taylor & Francis inc, 2015) Durak, Halil; Genel, Yasar; Calban, Turan; Kuslu, Soner; Colak, Sabri
The aim of the study was to investigate the optimization of the dissolution of tincal ore in phosphoric acid solutions at high temperatures in a batch reactor. The effect of the following parameters on the dissolution process was investigated: the reaction temperature, the phosphoric acid concentration, the particle size, and the solid-to-liquid ratio. The best conditions for the dissolution were determined using the 2(4) factorial experimental design method. The optimum values of the parameters were experimentally determined. The effective parameters were the reaction temperature, the phosphoric acid concentration, the particle size, and the solid-to-liquid ratio. The optimum conditions resulted in the maximum boron dissolution at an acid concentration of 1M, reaction temperature of 85 degrees C, particle size of 4.75 mesh, and solid-to-liquid ratio of 1/6 g.mL(-1). Under these optimum conditions, the best dissolution yield was 98.26%.