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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 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 Elbistan linyiti, turba ve biyokütlenin sıvılaştırma olanaklarının araştırılması(İnönü Üniversitesi, 2016) Karta, MesutDüşük kalorifik değeri, yüksek kül ve nem içeriği nedeniyle Elbistan linyitleri Afşin-Elbistan termik santralinde yakıt olarak kullanılmaktadır. Fakat bu özelliğe sahip olan linyitlerin çevre kirliliği açısından doğrudan yakılmaları uygun değildir. Endüstriyelleşmeye bağlı olarak artan enerji ihtiyacını karşılamanın yanı sıra çevrenin korunması da gerekmektedir. Bu nedenle son zamanlarda kömürden ve kömür-biyokütle karışımlarından piroliz, gazlaştırma ve sıvılaştırma işlemleri ile temiz enerji elde edilmesi üzerine çalışmalar yoğunlaşmıştır. Bu tez kapsamında, Elbistan linyiti, Adıyaman–Çelikhan turba ve Balıkesir pirinanın doğrudan kömür sıvılaştırma yöntemi ile tek başlarına ve birlikte sıvılaştırma potansiyelleri incelenmiştir. Deneysel kısımda başlangıç maddelerinin parçacık boyutunun, karışım tipi (linyit:turba ve linyit:pirina) ve oranının, sıvılaşma ürünleri olan, kalıntı, asfalten, preasfalten, yağ ve gazların verimi ve kimyasal yapıları üzerine olan etkileri detaylı olarak araştırılmıştır. Sıvılaştırma ürün verimleri kütle denkliğinden, ürünlerin kimyasal yapıları ise XRD, FTIR, DTA/TG, SEM, elementel ve kısa analiz, kalorimetre ve GC/MS analizleri ile aydınlatılmıştır. Buna ek olarak başlangıç maddelerin kimyasal yapıları ve morfolojik özellikleri aynı analizler ile belirlenmiştir. Deneysel sonuçlar, başlangıç maddelerinin seçilen parçacık boyutlarının sıvılaştırma ürünlerinin kimyasal yapılarına ve verimine bir etkisi olmadığını göstermiştir. Yağ verimi linyit, turba ve pirina sırasına göre artmıştır. DTA ve TG sonuçları, linyit ile tez kapsamında kullanılan biyokütle arasında bir sinerji olacağını göstermiş, en yüksek yağ verimi linyit ve biyokütlenin birlikte sıvılaştırılması ile elde edilmiştir.Öğe Interface-Engineered P2-Type Cathode and Biomass-Derived Anode for Stable Sodium-Ion Full Cells(Wiley-V C H Verlag Gmbh, 2025) Dogan, Ebru; Moeez, Iqra; Chung, Kyung Yoon; Whba, Rawdah; Altin, Emine; Harfouche, Messaoud; Karta, MesutThis work presents a sustainable and high-performance sodium-ion full-cell architecture by combining a core@shell Na0.67Mn0.5Fe0.5O2@Al2O3 cathode with a hard carbon anode derived from cherry seed biowaste. The P2-type cathode material is synthesized via a conventional solid-state method and coated with Al2O3 using a scalable wet-chemical route. Structural and surface analyses confirmed the formation of a uniform Al2O3 shell, which enhanced the cathode's electrochemical stability by mitigating Mn3(+)-induced distortion and suppressing electrolyte side reactions. In parallel, the hard carbon anode is produced from cherry seeds-a low-cost and abundant byproduct-through high-temperature pyrolysis, delivering high capacity and excellent cycling performance. Electrochemical evaluation of both electrodes in half-cell and full-cell configurations revealed favorable sodium-ion diffusion, robust structural integrity, and improved interfacial properties. The half-cell, assembled with Na0.67Mn0.5Fe0.5O2@Al2O3 cathode, demonstrated remarkable cycling stability and rate capability within a practical 1.5-3.5 V window, retaining 94.5% capacity after 100 cycles. In situ XRD studies further elucidated the phase transitions and stability of the cathode during cycling. This study demonstrates a sustainable and scalable pathway for sodium-ion battery development by integrating surface-engineered cathodes and biomass-derived anodes.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 Sodium-induced phase shift in α-NaMnO2 and electrochemical properties of the full cells using hard carbon anodes derived from regional olive leaves(Springer Japan Kk, 2025) Dogan, Ebru; Ozcan, Sibel; Canbay, Canan Aksu; Karta, Mesut; Depci, Tolga; Altin, SerdarIn this study, we investigated the effect of excess sodium (Na) in a NaMnO2 structure using one-step heat treatment at 900 degrees C followed by quenching in liquid nitrogen (N-2). According to the X-ray diffraction (XRD) analysis, there was a competition between the monoclinic and orthorhombic phases, and we found that there were two monoclinic phases with similar structural properties. Therefore, we focused on revealing the formation of two isostructures of the monoclinic phase triggered by Na ions. We found that the lattice parameters and beta angle changed from 113 degrees to 105 degrees in the samples with increasing Na content. Structural analysis of the powders using the XRD data was conducted using Rietveld refinement, and the phase ratios for all samples were calculated. The sample with x = 1.3 showed a 95% alpha-phase. To understand the formation of the two isostructures, we performed Density functional theory (DFT) calculations to examine their band structure, stability, and formation energy. A structural analysis of the excess Na-doped samples was performed using common techniques, and it was found that excess Na caused the formation of a coating on the grains in the form of sodium oxide. To validate this prediction, we conducted inductively coupled plasma mass spectrometry (ICP-MS), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy coupled with energy dispersive X-ray (SEM-EDX) analyses using the basic properties of these techniques and their interactions with materials. In the second part of the study, we produced HC from locally sourced olive leaves and investigated their structural properties. The electrochemical properties of the electrode materials were examined using a half-cell configuration as electrodes with Na metal and a full-cell configuration using x = 1.3 cathode and HC anode. A direct-contact pre-sodiation strategy was used as the anode in the full-cell measurements. It was found that the full cells had initial capacity values of 150 mAh/g for the voltage range 1.5-4.3 V and 120 mAh/g for the voltage range 1.5-3.5 V.
