METHOD OF PRODUCING HOLLOW CERAMIC FIBRES Russian patent published in 2016 - IPC C04B35/624 D01F9/08 B82Y40/00 

FIELD: technological processes.

SUBSTANCE: invention relates to ceramic materials, particularly to producing hollow ceramic fibres used for production of capillaries, membranes, filters, separators in batteries compartments and composite materials. Due to their chemical inertia and high heat resistance such ceramic fibres can be used while operating in aggressive media and at high temperature of the working zone. Carbon fibres in the form of bundles or felt is washed with a mixture of acetone and alcohol in ratio of 1:1, then is coated with a hydroxide (aluminium, zirconium or titanium) layer of metal by impregnation in appropriate hydroxide ash. Hydroxide is dried at temperature of ~60 °C and annealed at 250-300 °C for 20-30 minutes to produce carbon-ceramic fibre. Procedure for impregnation-drying-annealing is carried out at least 3 times. Carbon core of the composite fibre is burnt out in air at temperature of 800-1,000 °C. Inner diameter of the obtained fibres corresponds to the diameter of the used carbon fibre and is equal to 5-7 mcm in examples given in the description. Structure of ceramic fibers repeats an outer structure of a carbon precursor, and therefore it is possible to produce bundles and felt from hollow ceramic fibres.

EFFECT: simple and accelerated method of producing hollow ceramic fibres without using special equipment and aggressive chemical agents.

1 cl, 15 ex, 8 dwg