Mannich reaction of lignosulfonate by graft copolymerization

There are three methods for preparing modified lignin flocculants: ① Mannich reaction of lignosulfonate; ② graft copolymerization of lignosulfonate; ③ modification of graft copolymer
.

Mannich reaction of lignosulfonate

[Preparation method] The Mannich reaction of lignosulfonate mainly uses part of the active groups (such as hydroxyl, etc.
) on the lignosulfonate to prepare an amphoteric modified lignin flocculant through Mannich reaction
.
Dissolve lignosulfonate (including sodium lignosulfonate , calcium lignosulfonate, magnesium lignosulfonate, etc.

Graft Copolymerization of Lignosulfonate

[Preparation method] The graft copolymerization of lignosulfonate mainly uses an initiator to initiate the sulfonate to generate free radicals, and then graft copolymerize with cationic monomers to prepare an amphoteric graft copolymer
.
Since the initiator has a low initiation efficiency for lignin, especially for lignosulfonate, the grafting effect is not very ideal