A method for coproducing
xylose, white
carbon black and
active carbon from
rice hulls comprises the following steps that: the
rice hulls are washed and boiled by water, and the
xylose is hydrolyzed by diluted acid; low-temperature
carbonization is carried out, then, reaction with concentrated alkaline is taken to extract
silicon dioxide, and the white
carbon black is prepared by a
coprecipitation method; and
solid is added into liquor zinci
chloride to be soaked for a certain time at a low temperature, then, high-temperature activation and
acid washing are carried out, the materials are washed by water to the
neutral state, and the materials are dried and ground to obtain
active carbon. In the method provided by the invention, one line is adopted for coproducing the
xylose, the white
carbon black and the
active carbon with high specific surface area in a
branch way, the xylose preparation process for continuously hydrolyzing the
hemicellulose in the
rice hulls is adopted for the xylose, the xylose yield is improved, the method belongs to a simple and feasible xylose preparation process, the white carbon black is prepared by adopting an advanced chemical
coprecipitation method, higher dispersing degree of the
precipitation particles is maintained through adding surfactants into a
solution system, and high-purity and ball-shaped white carbon black particles are prepared. The active carbon is activated by adopting the chemical
activation method, the
activation temperature is low, micro carbon crystals with small dimension can be favorably formed, and the active carbon with more developed
porosity and better absorption performance can be obtained. The method provided by the invention has the advantages that the integrated and sufficient utilization of the rice hulls is realized, the maximum use of raw materials is realized, the integrated investment is low, the process technology is simple, and the industrialized production is easy to realize.