Nuray Oktar

Etherification rates of 2‐methyl‐2‐butene and 2‐methyl‐1‐butene with ethanol for environmentally clean gasoline production

Etherification of C5 reactive olefins available in light fluidized catalytic cracking (FCC) gasoline is an attractive way to decrease the olefins and to increase the octane number. The reactivities of 2-methyl-1-butene (2M1B) and 2-methyl-2-butene (2M2B) in the etherification reaction with ethanol catalysed by a strongly acidic macroreticular resin catalyst were investigated in a temperature range of 333–360 K using a liquid phase differential flow reactor. In the presence of excess alcohol, the apparent reaction orders of etherification reactions of isoamylenes were found to be 0.93 and 0.69 with respect to 2M1B and 2M2B concentrations, respectively. 2M1B was shown to be more reactive than 2M2B and its activation energy is also lower in the etherification reaction. It was also shown that diffusion resistances, especially in the macropores of the catalyst, may play an important role on the observed rates. © 1999 Society of Chemical Industry

Conversion of Biodiesel By-Product Glycerol to Fuel Ethers over Different Solid Acid Catalysts

In this study, the etherification reaction of glycerol (G) with tert-butyl alcohol (TBA) was investigated for the production of high quality transportation fuel additives. The reaction was carried out in liquid phase, in a continuous flow reactor in the presence of various solid acid catalysts. Activities of acidic resin catalysts, such as Amberlyst-15 (A-15), Amberlyst-16 (A-16) and Amberlyst-35 (A-35), Nafion-SAC-13 and ?-alumina were compared. Significant increase in conversion was observed with an increase in temperature. Amberlyst 15 showed the highest activity at about 110°C, giving glycerol conversion values of about 0.5 at a space time of 18 g cm-3 s. However, A-16 gave higher di-ether selectivity values. Nafion-SAC-13 showed activity at higher temperatures, while the activity of ?-alumina was very low, even at 400°C.

Activity Comparison of Acidic Resins in the Production of Valuable Glycerol Acetates

Abstract Acetates of glycerol have been produced in a heterogeneous reaction system using acidic ion-exchange resin catalysts; Amberlyst-15 (A-15), Amberlyst-16 (A-16), Amberlyst-36 (A-36), Amberlite-IR 120 (A-IR 120) and Relite-EXC8D (R-EXC8D). Effect of reaction temperature on glycerol conversion and product (mono, di and tri glycerol acetates) selectivities were investigated via reaction experiments conducted with glycerol to acetic acid initial molar ratio (G/Ac) of 1/6. Increase in glycerol conversion with an increase in temperature was observed for all catalysts. Among the catalysts investigated, R-EXC8D exhibited the highest activity in the temperature range of 95–150°C. Reaction was completed within a 25 minute short time period.

BİYODİZEL YAN ÜRÜNÜ GLİSERİNİN ESTERLEŞME VE ASETİLASYONU İLE DEĞERLİ KİMYASALLARIN ÜRETİMİ

Cevreci bir yakit olan biyodizel cesitli avantajlarindan oturu dizel yakita alternatif bir yakittir. Bitkisel yagin metanol veya etanol ile transesterlesmesiyle biyodizel uretilmekte ve yan urun olarak onemli miktarda gliserin olusmaktadir. Gliserinin asetik asitle esterlesmesi biyodizel uretiminden kaynaklanan artan gliserinin degerlendirilmesi acisindan alternatif bir cozum teskil eder. Yapilan calismada gliserinin asetik asitle esterlesme reaksiyonu Smopex-101 varliginda sivi faz kesikli otoklav reaktorde incelenmistir. Yapilan reaksiyon calismalarinda oda sicakliginda oldukca kisa surede (25 dakika) %100 gliserin donusumune ulasilmistir. Reaksiyon sicakligi ve baslangic reaktan molar oranlarinin gliserin donusumu ve urun seciciligi acisindan etkisi incelenmistir. En yuksek diasetin (%77) ve triasetin (%23) seciciligine 363K’de ve gliserin/asetik asit;1/12 molar oraninda ulasilmistir. Triasetin seciciligini artirmaya yonelik asetil klorur ile Smopex-101 varliginda asetilasyon reaksiyonu gerceklestirimistir. Oda sicakliginda gerceklestirilen calismalarda 1200 dakika sonunda %60 triasetin seciciligine ulasilmistir.