The invention relates to a preparation method for anionic
chitosan water-treatment flocculant. The method comprises the following steps: continuously dripping
chitosan acid solution with the percentage concentration by weight of 0.5 to 5% into strong
acid water solution according to the weight ratio of 1:0.1-0.8, stirring, mixing and reacting under 70 DEG C to 90 DEG C, dripping
aldehyde solution, performing
reflux reaction for 8 to 24 hours, neutralizing the obtained solution to the
pH range of 7 to 8, and dialyzing and
freeze drying to obtain a product. The preparation method has the advantages that the source of raw materials is wide, the preparation technology is simple and convenient, the requirements on temperatureand pressure during the synthesis process are simple, the production period is short, and industrial implementation is easy; the product is a
polymer material, is easy to degrade, has no
toxicity or
side effect and has the environmental-friendly property; the product can be directly added into waste water as well as added after being prepared into solution, the operation is simple, the
flocculation and
precipitation speed is high, and produced
solid impurities are easy to remove; the product is small in use amount and low in cost and has a good cation
flocculation effect.