摘要:
A process for producing oxygen-free or low-oxygen shaped bodies of silicon carbide, particularly SiC fibers, by using chemically reactive polysilanes and/or polycarbosilanes as precursors. In accordance with the invention green fibers are stabilized preferably in the presence of reactive gases.
摘要:
The liquid feed nozzle assemblies for a circulating fluid bed reactor comprise (i) a throttle body premixer to combine liquid feed with atomization steam upstream of a nozzle body to form a liquid feed/steam mixture comprising liquid feed droplets; (ii) a conduit connected to the venturi premixer and to a discharge nozzle body to convey a flow of the liquid/steam mixture created by the premixer to the nozzle body; (iii) a discharge nozzle connected to the flow conduit to shear the liquid feed/steam mixture to create liquid feed droplets of reduced size and (iv) a disperser at the outlet of the discharge nozzle to provide a spray jet of liquid feed having an increased surface area relative to a cylindrical jet. The nozzle assembles are particularly useful in fluid coking units using heavy oil feeds such a tar sands bitumen.
摘要:
A method for the preparation of a salt mixture useful for hardening steel parts, including of potassium cyanate, potassium carbonate and sodium carbonate, wherein 2.2 to 2.3 moles of urea is first reacted with 1 mole of potassium carbonate to form potassium cyanate. The escaping ammonia is converted with formaldehyde into hexamethylenetetramine. The reaction product, which is potassium cyanate and potassium carbonate, is ground, mixed with powdered sodium carbonate and pressed at between 80.degree. and 230.degree. C. into shaped pieces.