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Abstract

2,6-dimethyl naphthalane (2,6-DMN ) is an important dimethyl naphthalene (DMN) which is used in the synthesis of a new polymer polyethylene naphthalate’s (PEN) monomers 2,6-naphthalane dicarboxylic acid (2,6-NDCA). DMN’s are nine isomers and among them 2,6-DMN is the most important one. So far zeolites which have different qualities have been used for 2,6-DMN synthesis. In this work, methylation of 2 methyl naphthalene (2-MN) for synthesis of 2,6-DMN over Cu and La modified Y zeolite (CBV720, surface area=726m2/g\ SiO2/Al2O3=30), as experimental was intended for the finding of rate expression. In methylation reaction molar ratio of 1:5:5 2-MN:1,3,5 trimethyl benzene (mesitylene): methanol was fed into the reactor. For kinetic experiments, the changing of 2-MN conversion, the formation of 2,6-DMN and 2,6-DMN / 2,7-DMN ratio with different temperature, space velocity and catalyst were researched. For methylation kinetic, the rate expression depending on the 2MN and methanol concentration was determined. Arrhenius equation was used for calculation of frequency factor (ko) and activation energy (EA)

Keywords

• Y Zeolite, 2,6-DMN, Methylation, Zeolite catalyst, PEN

Cu-Y ve La-Y ZEOLİT KATALİZÖRLERİ ÜZERİNDE 2-METİLNAFTALİNİN METİLASYON KİNETİĞİ

Abstract

2,6-Dimetilnaftalin (2,6-DMN), yeni bir polimer olan polietilen naftalatın (PEN) monomerlerinden biri 2,6-naftalin dikarboksilik asitin (2,6-NDCA) üretiminde kullanılan önemli bir dimetilnaftalindir. Dimetil naftalinlerin dokuz adet izomeri vardır ve bunların içinde, 2,6-DMN en önemlisidir. Günümüze kadar 2,6-DMN sentezi için değişik özelliklere sahip zeolit katalizörler kullanılmıştır. Bu çalışmada, Cu ve La metalleri ile modifiye edilmiş Y zeolit (CBV720, yüzey alanı=726m²/g\ SiO₂/Al₂O₃=30) katalizörler üzerinde 2 metil naftalinin (2-MN) metilasyonuyla 2,6-DMN sentezinde, deneysel olarak metilasyon reaksiyonu hız ifadesinin bulunması amaçlanmıştır. Metilasyon reaksiyonunda reaktöre mol oranı 1:5:5 olan 2-MN: 1,3,5-trimetilbenzen (mezitilen): metanol karışımı beslenmiştir. Kinetik deneylerinde, 2-MN dönüşümünün, 2,6-DMN oluşumunun, 2,6-DMN/2,7-DMN oranının,  farklı sıcaklık, boşluk hızı ve katalizör ile değişimleri bulunmuştur. Metilasyon kinetiğinde, 2-MN ve metanol derişimine bağlı reaksiyon hız ifadesi bulunmuştur. Arrhenius denklemi yardımıyla frekans faktörü (k₀) ve aktivasyon enerjisi (E_A) de hesaplanmıştır.

Keywords

• Y Zeolit; 2,6-DMN; Metilasyon; Zeolit katalizör; PEN

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