化工四 B 林文翔 B 劉邦彥 B 彭子軒 Picture is modified and form ref.2

Synthesis of DMDCS Method1. Grinard method CH 3 MgCl+SiCl 4 → (CH 3 )SiCl 3 +MgCl 2 CH 3 MgCl+CH 3 SiCl 3 → (CH 3 ) 2 SiCl 2 +MgCl 2 Drawbacks: 1. Process isn’t selective. 2. Getting pure products by distillation of 120 plate columns. 3. Grignard reagent is expensive. Picture is form ref.2

Synthesis of DMDCS Method2. Direct method( G.E.) 2CH 3 Cl + Si/Cu 2 O → (CH 3 ) 2 SiCl 2 Advantages: 1. Simple 2. High purity and less cost. Furnace 370 ˚C M=CH 3 Cl Condenser

Flow chart Picture is modified and form ref.2 Discharge &preheat Recycle Mixed product

Cyclone separator Feed Si Output Feed Si Output Picture is modified and form ref.5

Fluid Energy Jet Mill Feed Crushing Classifying Picture is modified and form ref.3

Products Recycle material: Methyl chloride 1. CH 3 Cl ˚C [4] Main product: Methylchlorosilanes 1. (CH 3 ) 2 SiCl 2 70˚C 2. CH 3 SiCl ˚C 3. (CH 3 ) 3 SiCl57.3˚C Many other byproducts (only 1%): 1. Disilanes (CH 3 ) 3 Si 2 (CH 3 ) 3 113˚C [4] 2. Silaalkanes Cl 3 SiCH 2 SiCl ˚C [4] 3. Siloxanes C 6 H 18 OSi 2 101˚C [4] 4. Hydrocarbons C 2 H ˚C [4]

Separation by fractional distillation Picture is modified and form ref.2

Future work Reactor of Rochow synthesis

References 1.ROCHOW, E., The Direct Synthesis of Organosilicon Compounds Seyferth, D., Dimethyldichlorosilane and the Direct Synthesis of Methylchlorosilanes. The Key to the Silicones Industry. 2001,p 8-14 Massachusetts Institute of Technology Fluid energy jet mill Coulson,Richardson’s Chemical Engineering p.50