Abstract: A process is disclosed which comprises the steps of introducing a stream of the organic liquid onto a plurality of rotating reacting surfaces, rotating the reacting surfaces at a velocity such that the organic liquid is continuously formed into a thin film on each reacting surface and is continuously moved as a thin film towards the periphery of each reacting surface by centrifugal force, depositing over each thin film a substantially undiluted stream of a gaseous medium, reacting the organic liquid and gaseous medium on said rotating reacting surfaces, maintaining the pressure during reaction at subatmospheric levels, moving the resulting reaction products in a radially outward direction along each reacting surface and collecting said reaction product. An apparatus for carrying out such process is also disclosed.

Abstract: Liquid sulfur trioxide is stabilized against polymerization by incorporating therein a stabilizer combination of a normally liquid siloxane polymer with a methyl ester of an acid of boron.