Yazar "Duz, MZ" seçeneğine göre listele

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    Desulfurization of southeastern Anatolian asphaltites by the Meyers method
    (Elsevier Science Bv, 1997) Hamamci, C; Kahraman, F; Duz, MZ
    Southeastern Anatolian asphaltites are notoriously high in sulfur and therefore not suitable for direct use in combustion without extensive cleaning. In order to remove sulfur from asphaltites collected from Sirnak and Hazro, the Meyers (Fe3- salts) method was used. The effects of ferric concentration, coal particle size, temperature and time on the extraction efficiency were investigated and the experimental results are presented here. Most of the pyritic and sulfate sulfur was eliminated from the asphaltite samples. (C) 1997 Elsevier Science B.V.
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    Öğe
    Formation and characterization of humic acids from low rank anatolian coals by air oxidation
    (Taylor & Francis Inc, 2005) Erdogan, S; Duz, MZ; Merdivan, M; Hamamci, C
    The results of this study are aimed at evaluating the effects of air oxidation time, temperature and demineralization on humic acid production from two low-rank Anatolian coals. Two Anatolian low rank coals were studied at 120 and 200degreesC up to 10 days with and without demineralization. The best results for humic acid formation were obtained at a high temperature for longer times. Demineralization effect is negligible for studied coals. The rate of humic acid formation increased at first with increase in oxidation time, reached a maximum, and then decreased at high oxidation time. Also, a detailed study of the elemental composition, the characterization by FTIR, and the acidity of humic acids are reported.
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    Pyrolysis kinetics and chemical composition of Hazro coal according to the particle size
    (Springer, 2005) Duz, MZ; Tonbul, Y; Baysal, A; Akba, O; Saydut, A; Hamamci, C
    The relationship between particle size and chemical composition of Hazro coal (origin: SE Anatolia, Turkey) has been examined by elemental analysis and by thermogravimetric pyrolysis. The chemical composition of the coal was determined by grinding sample particles physically and separating according to their size in mm by sieving. Particle size distribution of the coal and chemical composition of these fractions were given. The coal has been non-isothermally pyrolysed in a thermogravimetric analyser to determine the kinetic factors. Thermal gravimetric (TG/DTG) experiments were performed from ambient temperature to 800 degrees C under a nitrogen atmosphere at heating rate 10 K min(-1) with five different particle size ranges. Kinetic parameters of the samples were determined using a Coats and Redfern kinetic model, assuming a first-order reaction. Depending on the particle size of the coal samples, the mean activation energy values varied between 49.1 and 84.6 kJ mol(-1). The results discussed indicate that activation energies increase as the particle size decreases.