自水达对 Reactions of Alkanes" ■Combustion 2 CH3CH2CH2CH3 13 O2 heat 8C02+10H20 Cracking and hydrocracking (industrial) long-chain alkanes catalyst shorter-chain alkanes Halogenation heat or light CH4 +Cl2 CH3CI CH2Cl CHCl3 +CCl4
Reactions of Alkanes ◼Combustion ◼Cracking and hydrocracking (industrial) ◼ Halogenation CH3CH2CH2CH3 + O2 CO2 + H2O heat 2 13 8 10 long-chain alkanes catalyst shorter-chain alkanes CH4 + Cl 2 CH3Cl + CH2Cl 2 CHCl 3 CCl 4 + + heat or light
1.The first step in petroleum refining is fractional distillation. Crude Oil Product Unit/Use Distillation: Temp(F): Recovered: Sentto: <90° Butane Gas The First Step Lighter Processing 90-200°- Light Straight Gasoline Naphtha Blending 200360°-Naphtha Catalytic Reforming Crude Hydro- oil 350-450°-Kerosene Treating 450-650°-Distillate Dist.Fuel Blending 650-1000° Heavy Fluid Catalytic Gas Oil Cracking 1000+8一 Residuum Coking
1. The first step in petroleum refining is fractional distillation
2.Upstream processing of the distillates. a.Catalytic hydrocracking-produces small alkanes from large alkanes by adding hydrogen. H2,heat Si-Al catalyst b.Catalytic cracking-produces small alkenes and alkanes by cracking in the absence of hydrogen. heat Si-Al catalyst c.Catalytic Reforming-the alkanes and cycloalkanes are upgraded to higher octane number by conversion into aromatic compounds. -H2 3H2 catalyst,heat catalyst,heat
2. Upstream processing of the distillates. a. Catalytic hydrocracking – produces small alkanes from large alkanes by adding hydrogen. H2 , heat Si-Al catalyst b. Catalytic cracking – produces small alkenes and alkanes by cracking in the absence of hydrogen. heat Si-Al catalyst c. Catalytic Reforming – the alkanes and cycloalkanes are upgraded to higher octane number by conversion into aromatic compounds. -3H2 -H2 catalyst, heat catalyst, heat
自秋标转材 Questions Light CH4+CI-CI H-CI CH3CI CH2Cl2+CHCl3+CCl CH3CH3 CH2CICH2CI+....... Requires heat or light for initiation. The most effective wavelength is blue, which is absorbed by chlorine gas. Lots of product formed from absorption of only one photon of light (chain reaction). ■The Mechanisms? Relative Reactivities?
Questions ◼ Requires heat or light for initiation. ◼ The most effective wavelength is blue, which is absorbed by chlorine gas. ◼ Lots of product formed from absorption of only one photon of light (chain reaction). ◼The Mechanisms? ◼Relative Reactivities? + Cl - Cl Light + CH3Cl + CH2Cl 2 + CHCl 3 + CCl 4 CH3CH3 + CH2ClCH2Cl + ....... CH4 H - Cl
Mechanism 0秋特对 批申院 Free-Radical Chain Reaction Initiation generates a reactive intermediate. Propagation:the intermediate reacts with a stable molecule to produce another reactive intermediate (and a product molecule). Termination:side reactions that destroy the reactive intermediate. movie
Mechanism Free-Radical Chain Reaction ◼Initiation generates a reactive intermediate. ◼Propagation: the intermediate reacts with a stable molecule to produce another reactive intermediate (and a product molecule). ◼Termination: side reactions that destroy the reactive intermediate. movie