Formulations and applications of commonly used deinking agents

Flotation deinking is to dilute the concentration of purified waste pulp to 0.8% ~ 1.2%, into the flotation machine, add deinking agent 

and a small amount of foaming agent to the slurry, at room temperature, air is pumped into the flotation separation, printing ink, 

pigment and other impurities are removed with the foam, and then dehydration and drying is the finished product. 

Deinking agents may also be added during the disintegration process. In flotation deinking process, the use of alkyl phenol 

polyoxyethylene (7 ~ 12) ether or fatty alcohol polyoxyethylene (7 ~ 12) ether, and their complex with alkyl benzene sulfonate 

or α-enyl sulfonate as deinking agent can obtain excellent deinking effect, using C15 ~ 18 according to 50:25:25 ratio. 

The compound surfactant of sodium α-alkenyl sulfonate with nonylphenol polyoxyethylene (4) ether and nonylphenol 

polyoxyethylene (15) ether is more effective as deinking agent. Some polyoxyethylene ether phosphate salts are also 

good deinking agents for flotation deinking. Flotation deinking of waste newspapers is carried out with a mixture of 0.2% surfactant, 

l. 5% NaOH, 4% Na2Si03 and 0.75% H2O2. It is generally believed that the difficulty of deinking is closely related to the amount of deinking agent used. 

However, in the deinking process of waste paper, it is also an important aspect to install thermal insulation towers to improve the reactivity of deinking drugs.