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Öğe Characterization of Products Obtained by Co-Liquefaction of Elbistan Lignite and Apricot Kernel Shell(Iop Publishing Ltd, 2019) Karaca, Huseyin; Olam, Mikail; Cavusoglu, BugraIn this study, the characterization of products obtained with the co-liquefaction of Elbistan lignite and biomass is made by using the apricot kernel shell as the biomass. The liquefaction tests were carried out in an inert atmosphere in non-catalytic conditions. The calorific value, proximate and elemental analyses of the solid products and the calorific value, elemental analyses and the qualitative and quantitative analysis of the liquid products obtained with the liquefaction were made. The qualitative and quantitative analysis were made by the gas chromatography-mass spectrometry. After the characterization process, the effect of the process parameters on the composition of solid and liquid products were also determined.Öğe Characterization of products obtained of waste polyethylene terephthalate by pyrolysis(Wiley, 2022) Olam, Mikail; Karaca, HuseyinIn this study, waste polyethylene terephthalate (wPET) was converted to liquid fuel by the pyrolysis method. It was also investigated both effects of microwave pre-treatment and catalyst (sodium borohydride) on total conversion and oil + gas yield. The reaction temperature of 375-425 degrees C and the reaction time of 30 min are sufficient for the pyrolysis of waste plastic samples in a batch reactor. In the pyrolysis of wPETs, the highest oil + gas yield of 45% was obtained under the conditions of reaction temperature of 425 degrees C and reaction time of 30 min. The highest total conversion was 62% of microwave pre-treated wPETs under catalytic conditions. It can be argued that microwave pre-treatment and NaBH4 influence the oil + gas yield in pyrolysis experiments. According to the gas chromatography-mass spectrometry (GC-MS) analysis results of the oil products, they consist of aromatic, mono and multi-ring aromatic compounds and polyaromatic compounds. Higher heating values of the solid products obtained in pyrolysis are approximately 4000-6000 cal/g. According to X-ray diffraction analysis (XRD) of the solid products, they consist largely of crystalline terephthalic acid (C8H6O4).Öğe Co-liquefaction Behaviour of Elbistan Lignite and Olive Bagasse(Iop Publishing Ltd, 2016) Karta, Mesut; Depci, Tolga; Karaca, Huseyin; Onal, Mehmet; Coskun, M. AliIn the present study, co-liquefaction potential of Elbistan lignite and Balikesir olive bagasse were investigated by direct coal liquefaction process. The olive bagasse is a cheap and abundant biomass, so it is used to decrease the cost of oil production from the lignite. The effect of blending ratio of the lignite and the olive bagasse on liquefaction conversion and oil yield were investigated. Characterization studies of the starting materials were done using XRD, FTIR, DTA/TG and elemental analysis. Elemental compositions of liquefaction products were also determined and the composition of the obtained oil was identified by GC/MS. DTA and TGA results indicated the synergistic effect of the lignite and the olive bagasse and maximum oil conversion (36 %) was obtained from 1: 3 blending ratio of lignite: olive bagasse. The results showed that the obtained oil was paraffinic-low waxy oil with 22.5 MJ/kg of calorific value and 0.95 g/cm(3) density.Öğe Co-Liquefaction of Elbistan Lignite with Manure Biomass; Part 1. Effect of Catalyst Concentration(Iop Publishing Ltd, 2017) Koyunoglu, Cemil; Karaca, HuseyinThe hydrogenation of coal by molecular hydrogen has not been appreciable unless a catalyst has been used, especially at temperatures below 500 degrees C. Conversion under these conditions is essentially the result of the pyrolysis of coal, although hydrogen increases the yield of conversion due to the stabilization of radicals and other reactive species. Curtis and his co-workers has shown that highly effective and accessible catalyst are required to achieve high levels of oil production from the coprocessing of coal and heavy residua. In their work, powdered hydrotreating catalyst at high loadings an oil-soluble metal salts of organic acids as catalyst precursors achieved the highest levels of activity for coal conversion and oil production. Red mud which is iron-based catalysed has been used in several co-processing studies. It was used as an inexpensive sulphur sink for the H2S evolved to convert Fe into pyrrohotite during coal liquefaction. In this study, Elbistan Lignite (EL) processed with manure using red mud as a catalyst with the range of concentration from 3% to 12%. The main point of using red mud catalyst is to enhance oil products yield of coal liquefaction, which deals with its catalytic activity. On the other hand, red mud acts on EL liquefaction with manure as a catalyst and represents an environmental option to produce lower sulphur content oil products as well.Öğe Co-liquefaction of Elbistan Lignite with Manure Biomass; Part 2-Effect of Biomass Type, Waste to Lignite Ratio and Solid to Liquid(Iop Publishing Ltd, 2017) Karaca, Huseyin; Koyunoglu, CemilMost coal hydrogenation processes require a large quantity of hydrogen. In general, a coal derived liquid such as anthracene oil was used as a hydrogen donor solvent. Tetralin, partially hydrogenated pyrene, phenantrene and coal-derived solvents, which contain hydroaromatic compounds, are efficient solvents to donate hydrogen. In an attempt to reduce the high cost of hydrogen, part of the hydrogen was replaced by a low cost hydrogen donor solvent. This must be hydrogenated during or before the process and recycled. To reduce the cost of hydrogen donor vehicles instead of liquids recycled from the liquefaction process or several biomass types, industrial by products, liquid fractions derived from oil sands bitumen were successfully used to solubilize a coal from the past. In an attempt to reduce the high cost of hydrogen, part of the hydrogen was replaced by a low cost hydrogen donor solvent. However, when hydrogen is supplied from the hydroaromatic structures present in the solvent, the activity of coal minerals is too low to rehydrogenate the solvent in-situ. Nevertheless, a decrease of using oxygen, in addition to enhanced usage of the hydrogen supply by using various waste materials might lead to a decrease of the cost of the liquefaction procedure. So instead of using tetralin another feeding material such as biomass is becoming another solution improving hydrogen donor substances. Most of the liquefaction process were carried out in a batch reactor, in which the residence time of the liquefaction products is long enough to favour the retrogressive reactions, early studies which are related to liquefaction of coal with biomass generally focus on the synergetic effects of coal while biomass added. Early studies which are related to liquefaction of coal with biomass generally focus on the synergetic effects of coal while biomass added. Alternatively, to understand the hydrogen transfer from biomass to coal, in this study, Elbistan Lignite (EL) with manure, tea pulp and waste plastic liquefied and to understand hydrogen quantity change after liquefaction, (H/C)(atomic) ratio of products obtained. Due to the highest oil conversion of manure biomass and highest (H/C)(atomic) ratio results show manure is the favourable biomass for EL amongst the other biomass used. And liquid/solid ratio optimized. About high total conversion of oil products the optimum ratio obtained as 3/1. And also EL with manure liquefied with the w/EL ratio between 0:1 to 1:1. As a result, by thinking about the yield values obtained, the optimum waste to lignite ratio found to be 1:1.Öğe Co-Liquefaction of Elbistan Lignite with Manure Biomass; Part 3-Effect of Reaction Time and Temperature(Iop Publishing Ltd, 2017) Koyunoglu, Cemil; Karaca, HuseyinMost of the liquefaction process were carried out in a batch reactor, in which the residence time of the liquefaction products is long enough to favour the retrogressive reactions. To minimize retrogressive reactions, the liquefaction of coal was carried out in a flowing solvent reactor in which a fixed bed of coal is continuously permeated by hot solvent. Solvent flowing through the coal bed carries the liquefaction products out of the reactor. Unlike experiments carried out under similar conditions in a batch reactor no increase in solid residue is observed during long time high temperature runs in the flowing solvent reactor. There is a greater appreciation of the importance of retrograde, or polymerization, reactions. If the free radicals formed when coal breaks down are not quickly capped with hydrogen, they react with each other to form large molecules that are much harder to break down than the original coal. Reaction time impacts both the co-liquefaction cost and the product yield. So as to study this idea, the experiments of Elbistan Lignite (EL) with manure co-liquefaction carried out by changing the reaction time from 30 to 120 minutes. As a result, the greatest oil products yields obtained at 60 minutes. Therefore, by thinking about the oil products yield values acquired, the optimal reaction time was obtained to be 60 minutes for Elbistan lignite (EL) with manure liquefied with the temperature of 350 degrees C and 400 degrees C. Above 425 degrees C did not examine because solvent (tetraline) loses its function after 425 degrees C. The obtained optimum temperature found 400 degrees C due to higher total conversion of liquefaction products and also oil+gas yields.Öğe Co-liquefaction of Tuncbilek lignite with algae (spirulina species): Effect of process parameters and characterization of chars and oils(Elsevier, 2022) Cavusoglu, Bugra; Koyunoglu, Cemil; Karaca, HuseyinNowadays, to reduce the cost of coal liquefaction and to produce a new liquid fuel alternative to petroleum, it is considered a more convenient method to liquefy coal and biomass together instead of solely coal liquefaction. Liquefaction experiments were carried out by changing the solvent/solid ratio of 1/1-5/1, reaction temperature 320-400 degrees C, reaction time 30-90 min, and algae/lignite ratio in the range of 1/1-5/1. As a result of this study, the most suitable process parameters obtained by considering total conversion are; solvent/solid ratio 3/1, reaction time 60 min, algae/lignite ratio 4/1, and reaction temperature 380 degrees C. Under these conditions, the highest total conversion is approximately 80% and 77% in catalytic and non-catalytic conditions, respectively. Under non-catalytic conditions of co-liquefaction experiments due to the GC-MS results, cyclopentane (raw material of motor oil), pentadecane, 2-methyl-naphthalene, octa-ethylene glycol, ethylene oxide heptamer are the main products of optimum parameters aforementioned for oil. They are mainly used in fuel technology and used in the chemical industry as raw materials mean low-cost production as well.Öğe Co-liquefaction of Yataan lignite and waste tire under catalytic conditions. Part 1. Effect of fresh tetraline and recycled tetraline on the conversion(Taylor & Francis Inc, 2018) Koyunoglu, Cemil; Eksioglu, Oktay; Yildirim, Onur; Karaca, HuseyinIn this study, the effect of solvent type and the solvent/solid ratio on the liquefaction of Mula-Yatagan lignite (YL) combined with waste tire (WT) under catalytic conditions investigated. Liquefaction experiments carried out the following conditions, a reaction temperature of 400 degrees C, a catalyst concentration of 3%, solvent/solid ratio from 1/1 to 9/1, reaction time of 90 min, lignite/waste ratio of 1/1. In addition, mixing speed was 400 rpm, and the nitrogen gas pressure fixed at 30 bar. After the each of liquefaction experiments finished, the soluble products (SP) classified as preasphaltene (PAS), asphaltene (AS) and oil+gas (OG), by solvent extraction. Due to the optimum total conversion determined, fresh tetraline obtained as the most favorable solvent with 71.71%, for the liquefaction of YL with WT. However, the total conversion for recycling tetraline is 68.6%. According to the results, co-liquefaction of YL combined with WT using recycle solvent is the one way to offer, alternatively of using crude oil, producing SP for not crude oil, producing SP for not only fuel-oil production but also prefer chemical raw materials. With respect to the optimum oil+gas yield results, the most convenient solvent type and the solvent/solid ratio are the recycled solvent and its 3/1 ratio.Öğe Co-liquefaction process olive bagasse and peat with lignite and the effect of biomasses on the products and oil yield(Pergamon-Elsevier Science Ltd, 2018) Depci, Toga; Karta, Mesut; Karaca, HuseyinIn the present study, instead of the burning the Elbistan lignite (L) having low calorific value and the biomasses (Balikesir Olive Bagasse OB and Adiyaman peat P), co-liquefaction process was conducted in order to produce valuable product as an oil. The effect of the biomasses ratio in the mixture on the properties of the co-liquefaction products and oil yield was also investigated in detail. The chemical characterization, composition and calorific value of the starting materials and the co-liquefaction products (char, asphaltene, preasphaltene and oil) were determined using XRD, FTIR, calorimeter, GC/ MS and elemental analysis. In addition, the morphological and thermal behavior of the starting materials was also investigated by TG/DTA and SEM. The results showed that the biomasses accelerated thermolysis of the lignite due to their amount of volatile content, cellulose, hemicelluloses and lignin in the structure causing the high total conversation ratio. The highest oil yield was obtained as 39.5% for L:P:OB (1:2:3). Calorific values of the char, asphaltene, preasphaltene and oil were determined as 1235 kcal/kg, 9080 kcal/kg, 8650 kcal/kg and 5135.19 kcal/kg, respectively. The obtained oil was identified as a paraffinic-low waxy oil whose density is 0.94 g/cm(3). (C) 2018 Elsevier Ltd. All rights reserved.Öğe Co-processing behavior of Golbasi lignite and poplar sawdust by factorial experimental design method(Pergamon-Elsevier Science Ltd, 2019) Karaca, Huseyin; Koyunoglu, Cemil; Ozdemir, Ali; Ergun, KenanIn this work, the liquefaction of coal and biomass with direct liquefaction strategy was explored. The point of liquefaction is both to utilize a greater amount of the current coal and biomass assets all the more productively and to create an alternative liquid fuel to oil. Along these lines, the procedure parameters must be resolved to expand the liquefaction efficiency. In addition, it is proposed to do the liquefaction efficiency, particularly in the reactant conditions, to expand the measure of oil. Process parameters were controlled by utilizing Factorial Experimental Design technique in the liquefaction procedures. The solid/liquid ratio was changed as 1/2-1/4, the catalyst concentration was 2-6%, the temperature was 375-400 degrees C and the duration was 30-90 min. Starting nitrogen pressure was set at 30 bar, stirring speed was 400 rpm, coal/biomass proportion was settled at 1/1. Tetralin as a solvent and MoO3 as catalyst were utilized. Toward the finish of the liquefaction procedure, the total conversions were computed in view of the acquired non-reactive solid (char). As indicated by the outcomes obtained, the most total conversion (81.9%) was acquired at a solid/liquid proportion of 1/2, a catalyst concentration of 2%, a reaction time of 90 min and a reaction temperature of 400 degrees C. In light of total conversions and elective liquid fuel (oil) in the given conditions, the solid/liquid ratio should be taken as 1/2, the catalyst concentration is 2%, the reaction time is 30-90 min and the reaction temperature is 400 degrees C. The lowest reaction time found, in this study, is the innovative solution for reducing co-liquefaction cost preferred. (C) 2019 Elsevier Ltd. All rights reserved.Öğe Developing an adaptive catalyst for an FCC reactor using a CFD RSM, CFD DPM, and CFD DDPM-EM approach(Elsevier Sci Ltd, 2023) Koyunoglu, Cemil; Gunduz, Figen; Karaca, Huseyin; Cinar, Tamer; Soyhan, Galina GulsenCyclone separators, which have an important role in the recovery of catalysts, constituted one of the aims of the study. In the work to be done, the pressure drop occurring during the fcc reaction is also calculated using the Ergun equation and it is aimed to provide the same value in a cyclone separator. In this study, which was presented for the first time in the literature, the best working conditions were determined by simulating the pressure drop in the cyclone separator modeled by using the various catalyst types namely NiMo/ASA-Al2O3, NiMo/p-Al2O3, NiMo/Y-Al2O3, Co-Mo, HZSM-5 zeolite, HY zeolite, pAl2O3, ASA-Al2O3, Y-Al2O3 determined from the literature in the Ergun equation. Among them, NiMo/ASA Al2O3, Co-Mo, HY zeolite, and ASA-Al2O3 were determined as the best catalyst for producing diesel from high oil fractions. Unlike previous studies, the condition that the cyclone separator modeled cleans the catalyst with maximum efficiency also determines the condition that provides low catalyst porosity in the determination of the catalyst type to be determined in diesel production. Due to the accuracy between the calculated and the predicted pressure drop results (about 1,8%), HY zeolite is the best catalyst for cyclone separator geometry. It is widely used to convert high molecular weight hydrocarbon fractions, the high boiling point of petroleum crude oils into olefinic gases, more valuable gasoline, and other products. The purpose of the FCC unit is to increase the refinery conversion and white product yield by converting heavy vacuum gas oil (HVGO) into light hydrocarbons at high temperatures with the aid of fluid catalysis. These two zones (reactor and regenerator) are placed as two different pressure vessels. For these two different systems to work in harmony with each other, unlike in previous studies, the dense discreet phase-Eularian approach was used in the modeling of the catalytic unit and the discreet phase approach was used in the modeling of the cyclone separator. The values required for both processes to work together have been determined approximately.Öğe Effects of Process Parameters on the Co-Liquefaction of Elbistan Lignite and Apricot Kernel Shell(Iop Publishing Ltd, 2019) Karaca, Huseyin; Cavusoglu, Bugra; Olam, MikailIn this study, the co-liquefaction of Elbistan lignite and biomass investigated by using apricot kernel shell as a biomass type. The liquefaction experiments were carried out under inert atmosphere and non-catalytic conditions. The effect of particle size, coal/biomass ratio, and reaction temperature were examined as a process variable to determine the effect of process parameters on total conversion of products obtained by liquefaction and the conversion of liquefaction products.Öğe Hydrogen transfer during co-liquefaction of Elbistan lignite and biomass: liquid product characterization approach(Taylor & Francis Inc, 2018) Koyunoglu, Cemil; Karaca, HuseyinIn this study, Elbistan lignite (EL) and manure were liquefied under catalytic conditions in an inert atmosphere. Red mud, tetralin, and distilled water were used as a catalyst and solvent, respectively. The liquefaction studies were carried out under catalytic conditions in the catalyst concentration of 9%, solvent/solid ratio of 3/1, reaction time of 60 min, waste/lignite ratio of 1/3, and at temperature of 400 degrees C. Stirring speed and initial nitrogen pressure were kept constant at 400 rpm and 20 bar, respectively. At the end of liquefaction process, the soluble liquefaction products were separated by successive solvent extraction to preasphaltene, asphaltene, and oils. Oil products characterized by H-NMR to be able to differ hydrogen transfer from manure to EL surface. To obtain the hydrogen transfer way, liquefaction experiments conducted under inert atmosphere which does not related to hydrogen reaction, other above experimental conditions were kept same but only solvent type changed. The reason of using distilled water instead of tetraline is tetraline known as hydrogen donor but not water. Because water behaves supercritical conditions during the liquefaction stage. EL liquefied alone while using tetraline however EL liquefied with manure with using distilled water as a solvent. The obtained oil products form both experiments characterized by H-NMR. The radical groups diffraction and range values are not changed significantly shows that manure behaved as an hydrogen donor. So, EL with manure is the one great option to reduce cost of hydrogen source for direct coal liquefaction plant.Öğe Hydrogen Transfer during Liquefaction of Elbistan Lignite to Biomass; Total Reaction Transformation Approach(Iop Publishing Ltd, 2017) Koyunoglu, Cemil; Karaca, HuseyinGiven the high cost of the tetraline solvent commonly used in liquefaction, the use of manure with EL is an important factor when considering the high cost of using tetraline as a hydrogen transfer source. In addition, due to the another cost factor which is the catalyst prices, red mud (commonly used, produced as a byproduct in the production of aluminium) is reduced cost in the work of liquefaction of coal, biomass, even coal combined biomass, corresponding that making the EL liquefaction an agenda for our country is another important factor. Conditions for liquefaction experiments conducted for hydrogen transfer from manure to coal; Catalyst concentration of 9%, liquid/solid ratio of 3/1, reaction time of 60 min, fertilizer/lignite ratio of 1/3, and the reaction temperature of 400 degrees C, the stirred speed of 400 rpm and the initial nitrogen pressure of 20 bar was fixed. In order to demonstrate the hydrogen, transfer from manure to coal, coal is used solely, by using tetraline (also known as a hydrogen carrier) and distilled water which is not hydrogen donor as a solvent in the co-liquefaction of experiments, and also the liquefaction conditions are carried out under an inert (N-2) gas atmosphere. According to the results of the obtained liquefaction test; using tetraline solvent the total liquid product conversion percentage of the oil + gas conversion was 38.3 %, however, the results of oil+gas conversion obtained using distilled water and EL combined with manure the total liquid product conversion percentage was 7.4 %. According to the results of calorific value and elemental analysis, only the ratio of (H/C)(atomic) of coal obtained by using tetraline increased with the liquefaction of manure and distilled water. The reason of the increase in the amount of hydrogen due to hydrogen transfer from the manure on the solid surface of the coal, and also on the surface of the inner pore of the coal during the liquefaction, brings about the evaluation of the coal as a structure involved in the recycling through the liquefaction plant if it is being installed. As a result of this study, results obtained from oil + gas data shows that when distilled water is used instead of tetraline during liquefaction of EL combined with manure, abundant crude hydrogen transfer takes place not because of using distilled water as a solvent but only with manure considered as a hydrogen sources. Furthermore, while adding manure into coal of liquefaction is also an alternative for current oil production.Öğe LIQUEFACTION OF NIGDE-ULUKISLA OIL SHALE: THE EFFECTS OF PROCESS PARAMETERS ON THE CONVERSION OF LIQUEFACTION PRODUCTS(Estonian Academy Publishers, 2017) Kartal, Ozlem Esen; Akin, Serhat; Hascakir, Berna; Karaca, HuseyinIn this paper, the direct liquefaction of Turkish Nigde-Ulukisla oil shale in noncatalytic and catalytic conditions was studied. The effects of pressure, tetralin/oil shale ratio, catalyst type and concentration, reaction time and temperature and oil shale/waste paper ratio on the process were investigated. It was found that tetralin/oil shale ratio had no considerable effect on the total and liquefaction products conversions under the noncatalytic conditions. Fe2O3, MoO3, Mo(CO)(6), Cr(CO)(6) and zeolite were used as catalysts in catalytic liquefaction. The highest total and liquefaction products conversions were obtained using MoO3 as catalyst at a concentration of 9% by weight. Reaction temperature of 400 degrees C and reaction time of 90 minutes were chosen according to obtained liquefaction results. Co-liquefaction experiments were performed using waste paper. Both the total and oil + gas conversions were increased to a considerable extent by the application of the co-liquefaction process. According to gas chromatographic-mass spectrometric (GC-MS) analysis, the liquid product from the liquefaction process of oil shale under catalytic conditions of experiment 22 consisted mainly of naphthalene and its derivatives and polycyclic hydrocarbon such as indene and its derivatives.Öğe Liquefaction Potential of Adiyaman Peat(Iop Publishing Ltd, 2016) Karaca, Huseyin; Depci, Tolga; Karta, Mesut; Coskun, M. AliIn the present study, liquefaction potential of Adiyaman peat was studied by direct liquefaction technique to obtain oil as a fuel purposes due to its high carbon and hydrogen content and low sulphur ratio. The peat and liquefaction products, named char, asphaltene, preasphaltene and oil, were characterized by XRD, FTIR, SEM, DTA/TG and elemental analysis. The compositions of the obtained oil were also identified by GC/MS. The results indicated that the obtained oil was paraffinic-low waxy oil with 21.73 MJ/kg of calorific value and 0.93 g/cm(3) density and it was composed of naphthalene and phenolic groups. The oil conversion ratio was found to be 29 %.Öğe Microbial desulphurisation of coal: a review(Taylor & Francis Ltd, 2023) Koyunoglu, Cemil; Karaca, HuseyinDuring the production and processing of coal, burning it for energy production may cause a series of environmental pollution due to the amount of sulphur in it. When the consumed sulphur in coal is in the form of sulphur dioxide at the end of combustion, it reacts with water at high altitudes. Moreover, it goes down to the earth in the form of sulphuric acid, as well as damaging plants. The corrosive harmful impact on industrial plants is the removal of the sulphur in the coal when it is environmental. Microorganisms that use sulphur as food to eliminate the anxiety of clean production brought about by the chemical method. This review determined the study contains information about which microorganism is effective in removing sulphur in coal and also the types of organisms that should be according to the organic sulphur type in coal.Öğe Modelling DME production from synthetic gases with a fluidized bed reactor: A CFD approach(Elsevier Sci Ltd, 2021) Koyunoglu, Cemil; Karaca, Huseyin; Soyhan, Hakan SerhadDimethyl ether (DME) is one of the most sought-after automotive fuels. Catalyst is generally preferred in direct dime production from synthesis gas. 0In our study, Computational Fluid Dynamics is used for reactor modeling of DME production from syngas in a fluid bed model. It is aimed to determine the necessary conditions to ensure maximum gas-solid contact for the production of zeolite-catalyzed DME in a fluidized reactor, especially for the syngas produced by gasification method from domestic wastes. A distinctive feature of this approach is the physical optimisation simulation. The calculation of the bed density at which the catalyst active surface is provided at maximum contact has a very important place in determining the reactor operating conditions. In the study, firstly, the simulation model is compared with a real experimental fluidized bed model. In the subsequent optimization study, the conditions where the maximum solid-gas contact surface was achieved was sought. For this reason, the results obtained in the case of a bed density of 2200 kg/m(3) showed that the pressure drop increased positively across the bed. This means that the reaction time is reduced. Therefore, the bed density value of 2200 kg/m(3) (with a maximum volume fraction of 55%), is the ideal density value to ensure maximum gassolid contact compared to 2300 (with a maximum volume fraction of 55,8%), 2400 (with a maximum volume fraction of 59,5%), 2500 (with a maximum volume fraction of 58,9%), and 2600 (with a maximum volume fraction of 57,2%) kg/m(3).Öğe A new catalyst (colemanite) for coal-to-liquid technology; a case study for the liquefaction of Elbistan Lignite: the effect of colemanite and Fe2O3 catalyst blending(Pergamon-Elsevier Science Ltd, 2019) Koyunoglu, Cemil; Karaca, HuseyinIn this study, the colemanite (a natural calcium borate mineral, NCBM) and Fe2O3 used as a catalyst on the liquefaction of Elbistan Lignite (EL, which has the most reserves in the east of Turkey). The liquefaction experiments were carried out at the reaction temperature of 400 degrees C, the reaction time of 90 min, the solvent/solid ratio of 3/1, stirring speed of 400 rpm, and initial nitrogen gas pressure of 20 bar. Fe2O3 and colemanite were together prepared as a new catalyst. Research has been made the recent observation that the highest liquefaction product yields, especially from a series of valuable fractions, obtained, with the highest mineral content of lignite. According to that model colemanite mixed with Fe2O3 to decide if the mineral content effect on total conversion if mineral substances added separately from coal. Fe2O3 selected as the most suitable catalyst type. To understand how to affect colemanite (as an economical catalyst source and also has high reserves in Turkey) as a catalyst on the liquefaction of EL with waste paper. The experiment conditions fixed and so compared due to the total conversion values. Unlike previous studies, this study was 67.1% of the total fluid conversion without catalyst, but this value increased to 77.6% when 15% NCBM catalyst was used. The total conversion was up to 83.8% with the catalyst concentration of 3% Fe2O3. On the other hand, when only 3% of Fe2O3 was used, the total conversion was only 75%. As a result, the mixture of NCBM and Fe2O3 increased the liquefaction efficiency by 15% by the synergistic effect. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.Öğe Obtaining the best temperature parameters for co-carbonization of lignite (yatagan)-biomass (peach seed shell) by structural characterization(Cell Press, 2022) Gunduz, Figen; Akbulut, Yeliz; Koyunoglu, Cemil; Onal, Yunus; Karaca, HuseyinIn this study, Yatagan lignite (YL) and peach kernel shells (PKS) were originally taken separately and in a 1: 1 ratio by weight. Experiments were carried out in a 3-zone heated cylindrical furnace in a steel reactor. Structural characterization of all the solid products obtained was made by FTIR, XRD, and SEM analysis. When the FTIR and XRD spectra of the raw samples are examined, it is seen that they are rich in functional groups. It is seen that the PKS has aliphatic and aromatic structures and cellulosic structure -OH stresses (3500 cm(-1)). The sharp peak around 2918 cm(-1) in Yatagan lignite belongs to the aliphatic C-H stretch. In the XRD spectrum, it is seen that both structures are largely amorphous. The raw PKS contains 3 different amorphous macromolecular structures. Yatagan lignite, on the other hand, contains crystalline peaks of clay and inorganic structures, depending on the ash content, as well as the amorphous structure. As the temperature increases depending on the carbonization temperature, as seen in the FTIR spectrum, the peaks of the functional groups decrease and disappear with the disruption of small macromolecular structures. As a result of the structural adjustment with the temperature increase, M-O-M peaks around 1000 cm(-1) remain due to the aromatic C-H stretching and ash content. The paper centers around test assurance of operating temperatures in the consuming layer during co-carbonization. It is obtained that 800 degrees C is the best temperature condition for the co-carbonization process. It has been concluded that the chars obtained as a result of pyrolysis will be used as a solid fuel in both environmental (the lowest sulfur content) and economic (400 degrees C) sense. However, the fact that it has a very low sulfur content with the increase in the liquid and gas efficiency obtained at high temperatures again proves the production of an environmentally friendly liquid fuel.
