PRODUCTION OF VALUABLE CHEMICALS VIA ESTERIFICATION AND ACETYLATION OF GLYCEROL, BY-PRODUCT OF BIODIESEL

Öz

Biodiesel is an alternative fuel to gasoline due to its environmental and economical benefits. Glycerol is the main
by-product of the biodiesel production by transesterification of vegetable oil with methanol or ethanol. The
esterification of glycerol with acetic acid can be a good choice for utilization of by-product glycerol. In this work
esterification of glycerol with acetic acid was performed in liquid phase autoclave batch reactor in the presence
of Smopex-101. Complete glycerol conversion was achieved in the reaction studies even at room temperatures.
Effects of reaction temperatures and initial reactant molar ratios on the glycerol conversions and product
selectivity were also investigated. The maximum diacetin (77 %) and triacetin (23 %) selectivities were achieved
at 363 K and glycerol/acetic acid; 1/12 molar ratio. Acetylation reactions were performed with acetyl chloride in
the presence of Smopex-101 in order to increase triacetin selectivity. 66 % triacetin selectivity was achieved in
acetylation reaction studies in a period of 1200 minutes at room temperature.

Anahtar Kelimeler

• Smopex-101
• glycerol
• esterification
• acetylation

BİYODİZEL YAN ÜRÜNÜ GLİSERİNİN ESTERLEŞME VE ASETİLASYONU İLE DEĞERLİ KİMYASALLARIN ÜRETİMİ

Öz

Çevreci bir yakıt olan biyodizel çeşitli avantajlarından ötürü dizel yakıta alternatif bir yakıttır. Bitkisel yağın metanol veya etanol ile transesterleşmesiyle biyodizel üretilmekte ve yan ürün olarak önemli miktarda gliserin oluşmaktadır. Gliserinin asetik asitle esterleşmesi biyodizel üretiminden kaynaklanan artan gliserinin değerlendirilmesi açısından alternatif bir çözüm teşkil eder. Yapılan çalışmada gliserinin asetik asitle esterleşme reaksiyonu Smopex-101 varlığında sıvı faz kesikli otoklav reaktörde incelenmiştir. Yapılan reaksiyon çalışmalarında oda sıcaklığında oldukça kısa sürede (25 dakika) %100 gliserin dönüşümüne ulaşılmıştır. Reaksiyon sıcaklığı ve başlangıç reaktan molar oranlarının gliserin dönüşümü ve ürün seçiciliği açısından etkisi incelenmiştir. En yüksek diasetin (%77) ve triasetin (%23) seçiciliğine 363K’de ve gliserin/asetik asit;1/12 molar oranında ulaşılmıştır. Triasetin seçiciliğini artırmaya yönelik asetil klorür ile Smopex-101 varlığında asetilasyon reaksiyonu gerçekleştirimiştir. Oda sıcaklığında gerçekleştirilen çalışmalarda 1200 dakika sonunda %60 triasetin seçiciliğine ulaşılmıştır.

Anahtar Kelimeler

• Smopex-101
• gliserin
• esterleşme
• asetilasyon

Kaynakça

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