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2 nd FEZA School. “Industrial Applications of Zeolites, and the Relevance of Preparing Well Defined and Characterized Materials”. Avelino Corma ITQ - Valencia. CATALYST EUROPEAN MARKET (Billion $). YEAR. FIELD. CHEMISTRY. Car, Polymer,. (From intermediate to Fine. Refining and. Ch.
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2nd FEZA School “Industrial Applications of Zeolites, and the Relevance of Preparing Well Defined and Characterized Materials” Avelino Corma ITQ - Valencia
CATALYST EUROPEAN MARKET (Billion $) YEAR FIELD CHEMISTRY Car, Polymer, (From intermediate to Fine Refining and Ch emistry) Environmental 1998 0.9 2.8 2001 1.0 3.2 2005 1.3 3.7
STEPS IN A HETEROGENEOUS CATALYTIC REACTION • Diffusion of Reactants in the Pores • Adsorption of Reactants on the Surface • Reaction of Adsorbed Products in the Pores • Desorption of Products from the Surface • Diffusion of Products Out of Pores
Peculiarities of Zeolites and Zeotypes of Interest in Catalysis • High Surface Area • Molecular dimensions of the pores: Molecular Sieves • High adsorption capacity: Concentration effect • Possibility for controlling number and strength of active sites • Preactivation of molecules in the pores: Strong electric fields, molecular confinement.
Adsorption Properties of ITQ-29 compared with other zeolites
ITQ-32 zeolite containing 8R and 12R pores Pore volume (0.16 cm3/g) and pore apertures 3.5 x 4.3 Ǻ and can be prepared as a nearly pure silica zeolite and as aluminosilicate. In the latest case, acidic properties are developed Cantín et al. JACS
6 Temperature = 25ºC Pressure = 300 mbar propene 5 4 3 Gas Adsorption (wt%) 2 1 propane 0 0 10 20 30 40 50 Time(min) Selective Gas Adsorption by ITQ-32
USY (Si/Al=35) 60 H O O 40 O 1 , 3 d i o x o l a n e ( 7 ) Yield/% 20 O H O O 1 , 3 d i o x a n e ( 8 ) 0 0 25 50 75 100 Conversion/% PHENYL ACETALDEHYDE GLYCEROL ACETAL O H O O H O H O O H O H H O O + H O H O 2 6 7 8 2 - Bencyl-4-hydroxymethyl 2 -bencyl-5-hydroxy - 1 , 3 - d i o x o l a n e - 1 , 3 - d i o x a n e “Hyacinte”
ISOMERIZATION 7 TO 8 Cationic Intermediate 6.4Å 6.4 6.4 6.4 7.4Å 7.4 7.4 7.4 Å 7.4 7.4 7.4 7.4 13.6 13.6 13.6 13.6Å 12.8 12.8 12.8 12.8 6.5 6.5 6.5 6.5 Å Å Yield/% r /Ba Conversion 7/8 0 Catalyst Si/Al 4 10 / % Å 8.3 8.3 8.3 8.3 7 8 USY 35 1.80 93 58 35 1.6 Beta 15 1.45 85 57 26 2.0 12.25 12.25 12.25 12.25 Å MOR 10 0.08 33 28 5 5.6 Å 7.4 7.4 7.4 7.4 MCM - 41 50 1.70 36 26 10 2.6 ZSM - 5 40 0.34 54 46 8 7.7 Isomerization Intermediate p - TSA - 1.38 97 66 31 2.1
PARADIGMA: It is not possible during catalytic cracking of gas oil to produce high yields of LCO and propylene at the same time with a single catalyst Gases (propylene) Gas oil Gasoline Diesel (LCO)
Molecular Traffic Control in ITQ-33 10 MR (6.1 Å) propylene 18 MR (12.2 Å) CRACKING diesel gasoline propylene gas-oil CRACKING CRACKING propylene ITQ-33
ZEOLITE ITQ-33 A. Corma, M.J. Díaz-Cabañas, J.L. Jordá, C. Martínez, M. Moliner, NATURE (2006)
Catalytic cracking of Arabian light vacuum gasoil at 500ºC and 60 seconds time on stream. Yields (%) Molar ratio a b c d = = = Catalyst Conversion Diesel Gasoline C C /C iC /iC 3 3 3 4 4 (%) USY BASED 88.3 19.5 39.5 4.4 1.3 0.1 ITQ-33 BASED 86.1 23.3 25.1 9.0 3.7 1.1 aUCS = 2.432 nm, bConversion = diesel + gasoline + gases + coke; c, d Boiling points [216.1ºC-359.0ºC] and [36.0ºC-216.1ºC], respectively. A. Corma, María J. Díaz-Cabañas, José L. Jordá, C. Martínez M. Moliner, Nature (2006)
POSSIBILITIES OF MOLECULAR SIEVES IN CATALYSIS • Acid Catalysts • Basic Catalysts • Redox Catalysts • Catalyst Supports – Cooperative Effects
H H S i O O S i A l O O S i O O S i O S i A l S i O O S i S i A l O S i S i O S i O O S i O S i qH = 0.39 Si/Al = 3 qH = 0.40 Si/Al 7 H H A l O O A l O S i O S i O O A l A l O O S i A l S i A l O S i O S i A l O S i O O S i O S i qH = 0.37 Si/Al = 1 qH = 0.38 Si/Al = 1.7 Influence of Si/Al Ratio on the Charge Density of the Zeolitic Protons
Distribution of Acid Strength Versus Aluminium per Unit Cell Al/U.C. (Y zeolite)
B-Zeotype and Zeolite Acid Sites:Ionicity of the OH Bonds H H O O O O O O B S i A l S i O O O O O O O O QOQH = 0.422 0.457
Influence of Acid Strength of Zeolites on Product Distribution: Chemoselective Friedel-Crafts Alkylations of Benzene and Furane Derivatives by Allylic Alcohols R R OH HY HY stronger sites weaker sites R R
Beckmann Rearrangement: Influence of Acid Sites in Catalytic Behavior RING OPENING BECKMANN HYDROLYSIS REARRANGEMENT POLYMERIZATION OXIME Bridging Hydroxyls Internal Silanols External Silanols STRENGTH OF ACID SITES Nitriles, others -Caprolactam Cyclohexanone
FLUORIDE MEDIA Synthesis with OH- Synthesis with F-
Al/uc by chemical analysis Al+SiOH/uc by NMR minimum SiOH/uc 1.2 1.2 0 0.3 0.3 0 1.2 2.4 9.9 0.4 3.1 11.2 -80 -90 -100 -110 -120 -130 -140 (ppm from TMS) Comparison of calcined zeolite Beta(OH)and(F)
Pure Silica Zeolite Beta Free of Connectivity Defects • Adsorption Properties • 15 g n-Hexane/100 g zeolite • < 0.1 g water/100 g zeolite • 0.22 cc/g micropore volume (N2 adsorption)
PREPARATION OF CYCLIC ACETALS 2-(2-naphtyl)-2,4-dimetyl 1,3-dioxolane 2-(4-hydroxy-3-methoxy-phenyl)- 4-mtyl-1,3-diolane O O O H FLAVORS AND FRAGRANCES Vanilla O O O Blossom Orange R R O R 1 2 O O + 3 R R H 1 2 O O O H + H O O + O H 2 O R Ethyle ethylendioxyacetal acetate R R 4 3 4 R , R , R , R = H or alkyl 1 2 3 4 O H O O O H O O Hyacinte 2-bencyl-5-hydroxy 1,3-dioxane 2-bencyl-4-hydroxymethyl 1,3-dioxolane
“Apple Scent” O O O O O O + H O + H , - H O O O O H + E t O H 3 2 H O O O O H 2 3 1 E G F r u c t o n e 100 20 min 100 80 Fructone (90%) Fructone (91%) 80 60 USY(13) 60 Yield/% 40 Beta(13) Yield/% 40 20 Ácid (2%) 20 Ácid (4%) 0 0 30 60 90 0 Time/min 0 25 50 75 Time/min Fructone FRUCTONE
PROCESS OPTIMIZATION Reaction Conditions: I. 7.4% of catalyst, toluene reflux.II. 8 torr, 5% wt catalyst, T=40ºC. I: Toluene 100 80 II: Without solvent Yield: 94% Selectivity: 99% 60 II: Without solvent Yield/% 40 Beta (25-hydrophobic) 20 0 0 30 60 90 120 150 Time/min
O H O H ArH H O ArOH + RR'CH 2 O H TS-1 + ArOH H R R 30% H O 2 2 + O R ' O H R' O O N H 3 R H O N (Clerici et al.) R Versatile Titano-Silicate, TS-1, Zeolite Oxidation Catalyst with Aqueous Hydrogen Peroxide as Oxidising Agent
H O Yield % 70 50 70 2 2 Phenol Selectivity % 90 80 90 INDUSTRIAL PROCESES FOR PHENOL HYDROXYLATION WITH H2O2 PROCESS RHONE POULENC BRICHINA ENICHEM 2+ 2+ (HclO H PO ) Fe /CO (TS-1) 4 3 4 Phenol Conversion % 5 10 25 Catechol Ratio 1.4 2.3 1 Hydroquinone Tars x100 10 20 12 Tars + diphenols
CHARACTERIZATION OF Ti MOLECULAR SIEVES TECHNIQUEMOSTRELEVANTINFORMATION Chemical Analysis Total Ti content. XRD Crystallinity/presence of other phases/cell parameters TEM-SEM Crystal size IR 960 cm-1 band associated to Si-O-Ti. Raman 960 and 1126 cm-1 associated to Si-O-Ti. Anatase. NMR Broadening of the 29Si signal. UV-Visible IR Ti coordination/extraframework Ti. XPS Ti dispersion. X-ray Absorption Spectros- copy (XANES-EXAFS) Geometry and coordination of Ti.
PORE RESTRICTION OF TI-SI DURING OXIDATION OF ALKANES WITH H2O2. TON SUBSTRATE mol/mol-Ti Hexane 7.0 Reaction conditions: 2M Pentane 0.24 H O (30%) 10cc, 2 2 2,2 DM B 0.0 substrate = 10cc, C Hexane 0.37 Ti-Si = 1.0g, T=323K Time = 3h Heptane 4.5 Octane 0.50 Nonane 0.10 Tatsumi et al, Chem. Commun, 1990
H2O2 OXIDATION WITH TI-BETA EPOXIDATION OF OLEFINS Selectivity Initial reaction 5 Olefin Catalyst rate, r x10 Epoxide H O o 2 2 (mol/mol.s) 1-Hexene Ti-Beta 3.72 3.9 93 TS-1 8.18 94.7 100 2-methyl-2-pentene Ti-Beta 6.07 0.6 92 TS-1 2.39 76.7 90 1-methyl-1-cyclohexene Ti-Beta 4.52 0.9 91 TS-1 0 - - Reaction conditions: T=50ºC, t=2h; 33 mmol olefin; H2O2 : olefin = 1:4 mol ratio; 23.6 g methanol; 0.2 g catalyst
OXIDATION OF OLEFINS ON TS-1 AND Ti-Al BETA OH R3 R1 C C R4 R2 Ti-Beta O OH R3 R1 R3 R1 H2O2 C C C C TS-1 R4 R2 R4 R2 Ti-Al-Beta TS-1
INFLUENCE OF THE Al CONTENT OF Ti-BETA ON EPOXIDE SELECTIVITY: STRATEGIES FOR THE PREPARATION OF CATALYSTS. • Cogel • Seeding • Fluoride Media
INFLUENCE OF AL CONTENT IN Ti-BETA ON ACTIVITY AND EPOXIDE SELECTIVITY Sample Synthesis Chemical Composition TON Epoxide Method Si/Al % TiO (mol/mol Ti h) Selectivity (%) 2 BA4 OH- no 123 4.7 14.9 14.6 alkalines BC1 cogel 300 4.7 20.8 25.9 BS1 seeding 2.5 28.6 75.4 ¥ BF1 F- 2.5 32.2 96.4 ¥ 1-hexene, H2O2, CH3OH as solvent; results at 25% max. conv.
Pure Silica Zeolite Beta Free of Connectivity Defects • Adsorption Properties • 15 g n-Hexane/100 g zeolite • < 0.1 g water/100 g zeolite • 0.22 cc/g micropore volume (N2 adsorption)
Activity and Selectivity for Al-free Ti-Beta(F) and Ti-Beta(OH) in the Epoxidation of Methyl Oleate with H2O2 Conversion (mol%) Selectivity Catalyst TiO Methyl Oleate H O Epoxide H O 2 2 2 2 2 (% w/w) Ti-Beta(F) 2.2 81.2 96.6 95.1 55.7 Ti-Beta(OH) 3.3 27.6 97.5 80.2 17.8
O O O O H O + O O H O + 2 2 O H 1.5 mol 1.5 mol 1.5 mol 1.5 mol acetic acid anhydride peracid acid Aqueous hydrogen peroxide 70% 1:1 molar ratio of H O 2 2 and H O 2 O O O 2 H O + O H 2 O 3 mol 1.5 mol 1.5 mol O O O O O + + O H O O H 1 mol 1.5 mol 1 mol Baeyer-Villiger oxidation of ketones
Baeyer-Villiger oxidation with peracids O O O R C O H 3 O O O O R C O H + + 3 O O O O
ACETIC ACID ACETIC ANHYDRIDE Acetic Acid KETONE H2O2 PERACID Acetic Acid KETONE LACTONE LACTONE H2O2 FUTURE PROCESS ACTUAL PROCESS
Sn-Beta Zeolite
Chemoselective Baeyer-Villiger Oxidation with Different Catalysts O O O O + + O O O O o x i d a n t c o n v . / % S n - B e t a / H O 6 8 1 0 0 : 0 : 0 2 2 m C P B A 8 5 1 1 : 7 1 : 1 8 [ a ] T i - B e t a / H O 4 6 0 : 7 9 : 0 2 2 9 3 0 : 3 3 : 2 0 M T O / H O 2 2 [ a ] r e s t m i s s i n g t o 1 0 0 % w e r e o p e n i n g p r o d u c t s o f t h e e p o x i d e .
O O O O O O O O Baeyer-Villiger oxidation of bicyclo[3.2.0]hept-2-en-6-oneusing different oxidation systems R eactant Products c o n v . / % selectivity/% a Sn - Beta > 95 100 0 0 mCPBA > 95 29 34 37 a Enzymes 100 0 0 a MTBE as solvent at 30ºC, Reaction time, 2 h. As 67:33 mixture of isomers
Sn-Beta as solid Lewis-acid catalyst Synthesis of Melonal powerful, green, cucumber-like and melon odor
Sn-Beta as solid Lewis-acid catalyst Synthesis by chemoselective Baeyer-Villiger oxidation Synthesis by a Darzens reaction
Classification of zeolites and similar porous materials depending on the dimensions of channels 30 Mesoporous 20 18 Ox Pore Diameter (Å) MCM-41 12 Ox 10 10 Ox VPI-5 8 Ox ß, Y, ZSM-5 Erionita large medium extra large low Pore Size