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Figure 4.1 reactants products reactor macroscopic (microns to meters)
catalyst support active site substrate adsorption reaction desorption bed of catalyst particles porous carrier (catalyst support) product macroscopic (microns to meters) chemical engineering domain mesoscopic regime (nanometers to microns) microscopic (nanometers) chemistry domain
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Figure 4.2 catalyst surface substrate A B product C
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Figure 4.3 step kink edge terrace vacancy surface cluster
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dissociative nitrogen adsorption
Figure 4.4 Fe [1,1,1] 1 2 3 4 5 log (reaction rate) Fe [1,0,0] Fe [1,1,0] dissociative nitrogen adsorption ammonia production
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Figure 4.5 Fe surface K /K2O promoter p* p
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Figure 4.6 Bulk catalysts Impregnated Hydrothermal synthesis
(zeolites) Precipitation (silica/alumina) Fusion/ alloy leaching (mixed oxides, Raney metals) Sol-gel synthesis (mixed oxides, supports) Flame hydrolysis (fumed oxides, supports) Wet impregnation (automotive exhaust catalysts) Incipient wetness (Pt/Sn/Al2O3) Vacuum pore impregnation (Bi/Pb/SiO2) Ion-exchange (acidic zeolites) Anchoring/grafting (supported tm-complexes)
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Figure 4.7 Support preparation/ precursor treatment Gelation
Precipitation Impregnation Ion-exhcange Grafting/ anchoring Fusion/ alloy leaching Active phase preparation Post-treatment Drying Calcination Forming Extrusion Pelleting Filtration Activation
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Figure 4.8 – Al(OH)3 NaOH Ni sponge (Raney Ni) Ni + Al high-temp
fusing Ni/Al alloy
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Figure 4.9
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sodium aluminate template
Figure 4.10 autoclave 100–150 °C gel sodium silicate sodium aluminate template H2SO4 filtering, washing, drying, calcining ZSM5 crystals H-ZSM5 ion-exchange,
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Figure 4.11 narrow channels wider cages
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Figure 4.12 catalyst paste extrudates catalyst pellets template
cutting, drying, calcining
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Figure 4.13 C ‘active doughnut’ N catalyst particle
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Figure 4.14
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Figure 4.15 Vadsorbed Pressure P0 I B II III IV V VI
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Figure 4.16 200 400 600 800 Temperature (°C) TCD signal CuO CeO2
mass spectrometer temperature control unit thermal conductivity detector purge reactant gas, e.g. hydrogen catalyst sample oven 200 400 600 800 Temperature (°C) TCD signal CuO CeO2 Ce0.90Cu0.10O2 A B C
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Figure 4.17 primary electron beam Al2O3 support (100 – 400 KeV) Au
backscattered electrons secondary electrons Auger electrons X-rays photons transmitted electrons diffracted electrons loss electrons catalyst sample Ag Au 18 nm Al2O3 support
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Figure 4.18
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Figure 4.19 metal surface C O m1 m2 m3 m4
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Figure 4.20 catalytic converter ceramic monolith 1 mm g-alumina
washcoat Pt/Pd/Rh catalyst
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engine operating cycle
Figure 4.21 exhaust O2 level engine operating cycle oxygen release oxygen uptake
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Figure 4.22
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Figure 4.23
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Figure 4.24 reactants aqueous phase recycle products L = tppts
organic phase reactants products aqueous phase recycle L = tppts
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Figure 4.25
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Figure 4.26
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Figure 4.27
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Figure 4.28 RHorg + OH–aq R–interface + H2O Q+X– + RY
organic phase R–interface + Q+X–org Q+R–org + X–aq RX + Q+Y– interface Q+R–org + R’Xorg R’Rorg + Q+X–org Q+X– + Y– aqueous phase X– + Q+Y–
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Figure 4.29 Oct4NBr CaF2 + H2SO4 CaSO4 + 2HF CaF2 particle
organic solvent CaSO4 layer
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Figure 4.30 vaporiser reactor light/medium ends recovery
vapour recycle distillation units ethene vaporiser reactor acetic acid ethyl acetate acetic acid recycle
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Figure 4.31 hydrogen light ends n-butane olefin feed alkylate product
pretreatment reactor system hydrogen alkylate product n-butane light ends alkylation regeneration at moderate temperature
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Figure 4.32 methanol tri- glycerides reactor II reactor I FAME
(biodiesel) methanol reactor II separator II reactor I separator I tri- glycerides separator III > 98% glycerol
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Figure 4.33 > 99.9% water free fatty acids (FFA) methanol
reactive distillation column solid acid catalyst methanol evaporator FAME (biodiesel)
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Figure 4.34 hydrophobic surface with isolated acid site
hydrophobic surface with adjacent acid sites hydrophilic surface/ numerous acid sites
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Figure 4.35 dehydrogenation heat reactor exchanger separator
ethylbenzene condensate dehydrogenation reactor O2/air heat exchanger steam separator dehydrogenated mixture ethylbenzene recycle benzene toluene styrene monomer (product) tar inhibitor
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Figure 4.36
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Figure 4.37 Vadsorbed P0 Pressure A Ni on FER zeolite
B Enzyme immobilised on zeolite-Y C Zn particles (1 mm diameter) D Ru on mesoporous silica E Pd on microporous alumina F Macroporous silica/alumina G Pt on mesoporous polystyrene after first run before first run Pressure P0 Vadsorbed
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Figure 4.38
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Figure 4.39
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Figure 4.40
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Figure 4.41
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Figure 4.42
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Figure 4.43
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Figure 4.44
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