OLEİK ASİTTEN BİYODİZEL ÜRETİMİNİN KESİKLİ REAKTÖR VE MEMBRAN REAKTÖRDE KARŞILAŞTIRILMASI

Öz

Son yıllarda biyodizel, fosil yakıtlara sürdürülebilir bir alternatif olarak daha fazla ilgi görmektedir. Biyodizel, petrol dizel yakıtına kıyasla daha düşük egzoz emisyonlarına ve toksisiteye sahiptir. Bu çalışmada oleik asit ve etanol arasında esterleşme reaksiyonu ile biyodizel üretimi kesikli reaktör ve membran reaktörde gerçekleştirilmiştir. Kesikli reaktörde ve membrane reaktördeki dönüşümler karşılaştırılmıştır. Membran reaktörlerin geleneksel reaktörlere göre avantajı gösterilmiştir. Katalizör olarak homojen katalizör olan sülfürik asit kullanılmıştır. Membran reaktörde kullanılmak üzere hidrofilik olan PVA membranı sentezlenmiştir. Katalizör konsantrasyonunun (ağırlıkça %2, %4, %6), etanol/oleik asit molar oranının (3, 6, 9) ve sıcaklığın (45°C, 55°C, 65°C arası) oleik asit dönüşümüne etkisi kesikli reaktörde incelenmiştir. Optimizasyon ile belirlenen noktada aynı reaksiyon membran reaktörde de gerçekleştirilmiştir. Reaksiyonlar dört saat sürdürülmüştür. Hem parametrik hem de optimizasyon sonuçlarına göre kütlece katalizör konsantrasyonunun dönüşüme etkisinin düşük olduğu, sıcaklık ve molar besleme oranının ise asit dönüşümüne etkisinin yüksek olduğu görülmüştür. Kesikli reaktörde En yüksek dönüşüm değeri % 85,5 ile 65 °C sıcaklıkta, alkol: asit molar besleme oranı 6:1 iken, %4 katalizör konsantrasyonu ile elde edilmiştir. Etanol/oleik asit molar oranı 3, sıcaklık 55 °C ve katalizör oranı ağırlıkça %4 olduğunda kesikli reaktörde %50 oranında dönüşüm elde edilirken, membran reaktörde %75 oranında elde edilmiştir. Bu sonuçlara dayanarak aynı çalışma koşullarında, membran reaktörde elde edilen asit dönüşüm sonuçları kesikli reaktörlerden %26 oranında arttığı görülmüştür.

Anahtar Kelimeler

• Oleik asit
• esterleşme
• kesikli reaktör
• membran reaktör
• biyodizel

COMPARISON OF BIODIESEL PRODUCTION FROM OLEIC ACID IN BATCH REACTOR AND MEMBRANE REACTOR

Öz

In recent years, biodiesel has gained more attention as a sustainable alternative to fossil fuels. Compared to petroleum diesel, biodiesel has lower exhaust emissions and toxicity. In this study, the esterification reaction between oleic acid and ethanol was carried out in the presence of sulfuric acid, which is a homogeneous acid catalyst, to produce biodiesel. Experiments were carried out in both a batch reactor and a membrane reactor. The conversions in the batch reactor and the membrane reactor were compared. The advantages of membrane reactors over traditional reactors were demonstrated. A hydrophilic PVA membrane was synthesized to use in the membrane reactor. A parametric study has been done in a batch reactor. The effect of catalyst concentration (2%, 4%, 6% by weight), ethanol/oleic acid molar ratio (3:1, 6:1, 9:1), and temperature (ranging from 45°C to 65°C) on the conversion of oleic acid was investigated in a batch reactor. The study explored how varying these parameters influenced the efficiency of the esterification reaction. Following the optimization process, the reaction was also carried out under the same conditions in a membrane reactor to compare the results. This approach allowed for a detailed analysis of how each variable impacted oleic acid conversion, enabling an optimal set of reaction parameters to be determined for both reactor types. The reactions were conducted for four hours. According to both parametric and optimization results, it was observed that the effect of catalyst concentration (by weight) on the conversion was low, while temperature and molar feed ratio had a significant effect on acid conversion. In the batch reactor, the highest conversion of 85.5% was obtained at 65°C, with an alcohol-to-acid molar feed ratio of 6:1 and a catalyst concentration of 4%. When the ethanol/oleic acid molar ratio was 3, the temperature was 55°C, and the catalyst concentration was 4% by weight, a 50% conversion was achieved in the batch reactor, while a 75% conversion was achieved in the membrane reactor. Based on these results, it was observed that the acid conversion results obtained in the membrane reactor under the same operating conditions were 26% higher than those obtained in the batch reactors.

Anahtar Kelimeler

• Oleic Acid
• esterification
• batch reactor
• membrane reactor
• biodiesel

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