Y ZEOLİT KATALİZÖRÜNÜN 2-METİL NAFTALİNİN DİSPROPORSİYONUNA KATALİTİK ETKİSİ

Abstract

Polietilen tereftalat (PET)’a alternatif ve özellikleri PET’den daha iyi olan polietilen naftalat (PEN)’in üretiminde 2,6-Dimetil naftalin (2,6-DMN) önemli bir birleşiktir. 2,6-DMN, PEN’in monomerlerinden birisi olan 2,6-naftalindikarboksilik asitin ( 2,6-NDCA) sentezinde ana girdi maddesidir (Zhang 2010). 2,6-DMN üretimi bir çok araştırmacı tarafından çalışılmıştır (Lin 2006). 2,6-DMN üretiminde en önemli sorun, yüksek seçimlilikte ve yüksek dönüşümde ürün veren katalizör geliştirilmesidir. Bu çalışmada, Y zeolit katalizörü üzerinde 2-metil naftalinin (2-MN) disproporsiyonu ile dimetil naftalinlerin üretimi araştırılmıştır. Deneylerde besleme olarak molar bileşimi 1:1 olan 2-MN:Benzen karışımı kullanılmıştır. Reaktöre 2cm³ katalizör yerleştirilmiş ve bu katalizör azot ortamında aktivasyon ve test işlemine tabi tutulmuştur. Elde edilen gaz ürünler, soğuk etilen glikol sirküle edilen bir yoğuşturucu ile yoğunlaştırılmıştır. Yoğuşturucuda toplanan sıvı ürünler 60 metre uzunluğa sahip kapiler kolonlu GC-MS ile analiz edilmiştir.

 

 

Keywords

• : Polietilen naftalat (PEN); 2,6-Dimetil naftalin (2,6-DMN); Y Zeolit; Disproporsiyon

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Abstract

2,6-dimethyl naphthalene (2,6-DMN) is an important compound for polyethylene naphthalate (PEN) production which is an alternative for polyethylene teraphtalate (PET) and has better qualities than PET. 2,6-DMN is a precursor for 2,6-naphthalenedicarboxylic acid (2,6-NDCA) synthesis which is one of the monomers of PEN (Zhang 2010). Synthesis of 2,6-DMN have been studied by many workers (Lin 2006). In the production of 2,6-DMN, the most important problem is to develop catalysts giving products with high selectivity and high conversion. In this study, the production of dimethyl naphthalene via disproportionation of 2-methyl naphthalene (2-MN) over Y zeolite catalyst was investigated. In the experiments a solution which’s molar composition was 1:1 2-MN:benzene was used. 2 cm3 of catalysts were placed in the reactor and this catalysts were activated and tested under nitrogen medium. In exit of the reactor, obtianed gas products were condensed with a condenser circulating cold ethylene glycol. Liquid products obtained in condenser were analysed with GC-MS which has 60 meter capilar column

Keywords

• Polyethylene naphthalate (PEN), 2,6-Dimethyl naphthalene (2,6-DMN), Y Zeolite, Disproportionation

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