The invention provides a method for producing white
carbon black and
active carbon by using residual rice
hull ash after gasification, which comprises the following steps of: performing alkali solution impregnation,
drying and
roasting on the residual rice
hull ash after the gasification, which serves as a
raw material, to obtain a mixture of powdery water glass and carbon
powder; adding water into the mixture to dissolve the mixture and boiling the mixture to obtain a water glass solution and the carbon
powder; performing the reaction of the water glass solution and soluble
alkali metal acid
carbonate to obtain
silicon dioxide
hydrate; filtering the
silicon dioxide
hydrate; washing and
drying a precipitate to obtain the white
carbon black; and washing and activating filter residue of the carbon
powder to obtain the
active carbon, wherein an alkali solution can be recycled. In the method,
silicon dioxide in raw materials can well react with alkali, the impregnating absorption performance is good, the uniform
permeation is achieved quickly, and the
drying link can be switched immediately, so that the large
silo capacity for storing impregnated rice
hull ash is unnecessary; the anoxic
roasting temperature is low, so that the high-temperature
corrosion of a furnace body is avoided; the alkali solution can be recycled, so that the loss of chemical raw materials is reduced; the
intermediate product powder, which is the mixture of the water glass and the carbon powder, is easy to be separated and filtered; and a prepared white
carbon black product is high in purity and strong in activity.