Fluoride-free synthesis of mesoporous [Al]-[B]-ZSM-5 using cetyltrimethylammonium bromide and methanol-to-olefin activity with high propene selectivity

Yalcin, Busra Karakaya
İpek Torun, Bahar
Large ZSM-5 crystals containing [B]-sites and mesopores with 2.5 nm pore sizes are synthesized in a fluoride-free, low OH- medium using cethyltrimethylammonium bromide as mesoporogen and 1,6-diaminohexane as structure directing agent. Absence of extra-framework Al sites and low concentrations of silanol sites are evidenced by Al-27 MAS-NMR and in-situ FTIR analysis. The low-defect containing [Al]-[B]-ZSM-5 (Mes-[Al]-[B]-ZSM-5) is evaluated for catalyzing the methanol-to-olefins reaction and found to result in low coke formation (4.1 mg g(-1) h(-1)) and very low alkane and aromatic formation rates. The propene to ethene ratio of 4.3 observed using Mes-[Al]-[B]-ZSM-5 is found to be superior to that (1.9) of a nano-sized [Al]-[B]-ZSM-5 (crystal sizes around 36 nm). Small particle sizes for nano-sized [Al]-[B]-ZSM-5 is found to be effective for supplying a higher coke tolerance, but insignificant for olefin product selectivity.


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Uyar, Tamer; Toppare, Levent Kamil; Hacaloğlu, Jale (2001-02-23)
Strong evidence of fluoride substitution on the pyrrole ring during electrolysis has been observed in a systematic structural and thermal analyses of polypyrrole doped with BF4- by direct insertion probe-mass spectrometry. To get a better understanding, not only polypyrrole samples doped with different dopant levels but also dedoped polypyrrole samples, mechanical mixtures of polypyrrole and N(Bu)(4)BF4 were analyzed using pyrolysis mass and FTIR spectroscopy techniques.
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Türker, Burhan Lemi (2002-07-05)
The peripherally fluorinated Huckel type cyclacenes having 3-7 benzenoid rings (R) were considered for AM1 (restricted Hartree-Fock) type semiempirical quantum chemical treatment. The cyclacenes having one or two of the peripheries completely fluorinated constitute type-I and type-H structures, respectively. All of them were found to be stable. Type-I systems are endogenic but type-II structures, R:5 onwards are exogenic. The cryptoannulenic effect was found to be operative partly on the heats of formations...
Boron-doped Biphasic Hydroxyapatite/beta-Tricalcium Phosphate for Bone Tissue Engineering
Pazarçeviren, Ahmet Engin; Tezcaner, Ayşen; Keskin, Dilek; Evis, Zafer (Springer Science and Business Media LLC, 2020-06-10)
Boron-doped hydroxyapatite/tricalcium phosphates (BHTs) were synthesized to study boron uptake and correlate structural alterations of incremental boron addition (0 to 10 mol%). BHTs with a Ca/P ratio of 1.6 were prepared by a wet precipitation/microwave reflux method, sieved (< 70 mu m) and characterized. XRD and FTIR analyses revealed that boron slightly distorted apatite crystal, increased crystallinity (95.78 +/- 2.08% for 5BHT) and crystallite size (103.39 +/- 23.47 nm for 5BHT) and still, boron additi...
JELINEK, R; Özkar, Saim; OZIN, GA (American Chemical Society (ACS), 1992-07-01)
Na-23 double-rotation NMR (DOR) provides details on site specific adsorption and anchoring interactions in intrazeolite hexacarbonylmetal(0) complexes, M{M(CO)6}-Na56Y, where M = Mo and W, and their molecular photooxidation products, n{MO3-x}-Na56Y, over the full composition range 0 < m less-than-or-equal-to 16, 0 < n less-than-or-equal-to 32 and 0 less-than-or-equal-to x less-than-or-equal-to 1. The shifts, intensities, and line shapes of the Na-23 DOR resonances carry information on the environments of th...
Oleylamine-stabilized ruthenium(0) nanoparticles catalyst in dehydrogenation of dimethylamine-borane
DUMAN, SİBEL; Özkar, Saim (Elsevier BV, 2013-08-12)
Oleylamine-stabilized ruthenium(0) nanoparticles were in situ generated from the reduction of ruthenium(III) chloride by dimethylamine-borane during its dehydrogenation at room temperature. Nearly monodispersed ruthenium(0) nanoparticles of 1.8 +/- 0.7 nm size were reproducibly isolated from the reaction solution by filtration and characterized by TEM, XRD, HRTEM, B-11 NMR, ATR-IR and UV-visible spectroscopy. Oleylamine-stabilized ruthenium(0) nanoparticles are highly active catalyst in hydrogen generation ...
Citation Formats
B. K. Yalcin and B. İpek Torun, “Fluoride-free synthesis of mesoporous [Al]-[B]-ZSM-5 using cetyltrimethylammonium bromide and methanol-to-olefin activity with high propene selectivity,” APPLIED CATALYSIS A-GENERAL, pp. 0–0, 2021, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/90389.