Effects of Sorption Enhancement and Isobutene Formation on Etherification of Glycerol with tert-Butyl Alcohol in a Flow Reactor

Ozbay, Nalan
Doğu, Timur
In the presented work, liquid phase etherification reaction of glycerol (G) with tert-butyl alcohol (TBA) was investigated in a continuous flow reactor using Amberlyst-15 (A-15) as the catalyst. Some experiments were also repeated in a batch reactor at autogenous pressure. Effects of feed composition, reaction temperature (70-110 degrees C), and reaction pressure (1-5 bar) on the product distribution were investigated. When flow reactor pressure was reduced from S to 1 bar, enhanced glycerol conversion and isobutene formation were observed. Conversion of glycerol reached 66% at 110 degrees C, at a space time of 18 s . g . cm(-3). However, batch reactor results indicated glycerol conversion values over 90% with diether selectivity of about 36% at much longer reaction times, over 400 min. Results indicated significance of equilibrium limitations, which initiated the idea of performing sorption enhanced reaction experiments in the flow reactor using Zeolite 4A and SA as water adsorbents. Results of these sorption enhanced reactor experiments proved significant enhancement of glycerol conversion and diether yield by in situ removal of produced water during the etherification reaction. Among these two adsorbents, performance of Zeolite 4A was better. Diether selectivity increased from about 0.20 to values over 0.33 in the sorption enhanced reactor experiments performed with a zeolite/catalyst ratio of 4/1 at 90 degrees C.


KOCAK, HI; ARAS, L (Elsevier BV, 1990-07-01)
The solution behaviour of Na, Ba, Zn and Al ionomers of methyl methacrylate-methacrylic acid copolymer (P(MMA-MAA)) with different ion contents has been studied by viscosity and dipole moment measurements. Two solvents with different character are chosen for viscosity measurements: dioxane (ε = 2.22) and acetone (ε = 20.7). The expected polyelectrolyte behaviour of the ionomers in acetone is reflected by the viscometric measurements. Mean squared dipole moment 〈μ2〉 values are calculated over a temperature r...
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Boz, N; Doğu, Timur; Murtezaoglu, K; Dogu, G (Elsevier BV, 2004-08-10)
Activities of ion-exchange resin catalysts, having different hydrogen exchange capacities ranging between 5.1 and 1.3 meq H+/g, on the etherification reactions of 2M1B (2-methyl-1-butene) and 2M2B (2-methyl-2-butene) with ethanol were experimentally tested in a fixed bed reactor. These catalysts were prepared by the heat treatment of Amberlyst-15 catalysts at 220 degreesC at different durations of time and also by the synthesis of sulfonated styrene divinyl benzene cross-linked resins. Activity of these cat...
Effects of pH, Initiator, Scavenger, and Surfactant on the Ozonation Mechanism of an Azo Dye (Acid Red-151) in a Batch Reactor
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In this study, an initiator (Fe2+) and a scavenger (CO32(-)) were used at different concentrations in a batch reactor to investigate the reaction mechanism of ozonation of a model azo dye, namely Acid Red-151 (AR-151). Also, the effect of a nonionic surfactant known as a major pollutant in many industrial wastewaters, namely polyethylene glycol (PEG), was observed on the degradation rate of AR-151. The experimental parameters and their ranges were: pH (2.5-10), initiator (0.8-50mg/L of Fe2+), surfactant (10...
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Effect of Midsynthesis Addition of Silica to the Synthesis Medium on the Properties of MFI-Type Zeolite Membranes
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Thin zeolite membranes of MFI type were prepared on alpha-Al2O3 supports by midsynthesis addition of silica in a recirculating flow system at 95 degrees C The synthesis was started with the batch composition of 80SiO(2): 30TPAOH:1500H(2)O which was changed to 80SiO(2)center dot 9TPAOH:1500H(2)O by addition of silica Mkt 24, 48, or 72 h Compared to synthesis at constant composition. it is possible to affect the rates of nucleation and crystal growth to obtain membranes with better quality by changing the ove...
Citation Formats
N. Ozbay, N. OKTAR, G. DOĞU, and T. Doğu, “Effects of Sorption Enhancement and Isobutene Formation on Etherification of Glycerol with tert-Butyl Alcohol in a Flow Reactor,” INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, pp. 8788–8795, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32028.