Derya Yeşim Hopa

Pyrolysis of poppy capsule pulp for bio-oil production

The feasibility of biofuel production via the pyrolysis of poppy capsule pulp, the main waste product of Afyon Alkoloid Factory, was investigated. The poppy capsule pulp was shown to have a high volatile matter content (ca. 76%). Pyrolysis experiments were carried out in the temperature range 400–550°C (heating rate 18°C min−1 and holding time 20 min) under a nitrogen atmosphere. The chemical components of the bio-oil were characterized by Fourier transform infrared spectrometry and gas chromatography-mass spectrometry. The effects of pyrolysis temperature on the production efficiency and the calorific value of the bio-oil were investigated. The maximum bio-oil yield and its calorific value at 500°C were 23.6% and 31.6 MJ kg−1, respectively. The latter value is close to that of many petroleum fractions. This high-energy bio-oil is therefore a clean fuel precursor and can be upgraded into higher quality fuels.

Pyroplastic deformation behavior of vitreous porcelain bodies in presence of spodumene

Pyroplastic deformation tendency of vitreous body compositions is a major production problem. In this work, a vitreous sanitaryware body composition (ST) which was developed in a previous work was taken as standard, and the sodium feldspar content of this recipe was changed with spodumene as a source of Li2O. Six different compositions were formulated by applying two different approaches: weight percent formulation and Seger formulation. Bodies were fired at 1250xa0°C and after firing deformation, firing shrinkage, and water absorption values were measured. Pyroplastic deformation behavior of bodies was determined by using fleximeter with a peak temperature of 1250xa0°C. According to the results, it was observed that spodumene addition with Seger formulation gives better results than weight percent formulation. The body which contains 0.1xa0mol% of Li2O (L2 body) has deformation value which is 11% lower than that of standard body due to its different phase composition and microstructure than ST body.

KAOLEN TÜRÜNÜN SAĞLIK GEREÇLERİ PORSELEN BÜNYESİNİN PİROPLASTİK DEFORMASYONU ÜZERİNE ETKİSİ

Seramik saglik gerecleri yuksek sicaklik pisirimiyle uretilen camsi porselenler olduklarindan, piroplastik deformasyon bu urunlerde siklikla karsilasilan bir problemdir. Piroplastik deformasyonu onlemede mikroyapi duzenlemesinin onemi buyuktur. Mikroyapida ignemsi mullit kristallerinin miktarinin artirilmasi ve camsi faz icerisinde mullit ve kalinti kuvars kristallerinin homojen bir sekilde dagilmasinin piroplastik deformasyonu dusurmede etkin rol oynadigi daha onceki calismalarda gozlemlenmistir. Kaolenler, porselen icerisinde en ince tane boyutlu hammaddeler olduklarindan, kristal olusumu icin sadece reaktif bilesenler olmakla kalmayip ayni zamanda mikroyapinin homojenliginde buyuk rol oynamaktadirlar. Bu calismada, standart recetede yer alan kaolen turu ve miktarinin saglik gerecleri porselen bunyesinin piroplastik deformasyon ve diger fiziksel ve mekanik ozellikleri uzerindeki etkileri incelenmistir. Seger yaklasimiyla saglik gerecleri bunyesinde kaolen turu ve miktarlarinin modifiye edilerek bunyenin proplastik deformasyon ozelliginin ve fiziksel ozelliklerin kontrol edilebilecegi ortaya cikartilmistir.