The invention relates to
biochar prepared by co-
pyrolysis of excess
sludge and hazelnut shells and a photocatalytic modification method of the
biochar. The method comprises the following steps: dryingand crushing the excess
sludge and hazelnut shells, proportionally mixing, adding a
potassium carbonate solution, soaking,
drying, carrying out vacuum
pyrolysis, sequentially washing with diluted
hydrochloric acid and deionized water, and
drying to obtain the
biochar. The method comprises the following steps: dissolving
zinc chloride in deionized water, adding a corresponding amount of
sodium hydroxide under a stirring condition, completely dissolving and adding biochar, placing the prepared solution in a glass
bottle, standing at a constant temperature under a closed condition until the reaction is complete, and cooling to
room temperature to obtain the nano ZnO composite biochar material. According to the method, the residual
sludge and hazelnut shells containing a large amount of organic matters are mixed and pyrolyzed to prepare the biochar, and the activated pore-forming method of
potassium carbonate solution soaking is combined, so that the
pyrolysis process is easier to occur,compared with
crop pyrolysis
modes such as direct
incineration, pyrolysis and addition of corn
straw, the method is simple, and the biochar product which is high in yield, large in specific surface area and good in
porosity and has photocatalytic performance is more favorably formed.