A pyridinium-functionalized chitosan derivative as ecofriendly carrier for efficient adsorption and controlled release of 2,4-dichlorophenoxyacetic acid sodium.

Herbicides with wide use and low efficiency in agriculture severely threaten the environment. However, employing adsorbents and controlled-release formulations (CRFs) can alleviate these environmental risks. Herein, a pyridinium-functionalized chitosan derivative (PFCS) was prepared successfully and characterized by various techniques.

Enhanced removal of Cr(VI) by polyethyleneimine-modified bamboo hydrochar.

Hydrochar is an environmentally friendly and cheap adsorbent, but its adsorption amounts for anions is very limited. The functionalized hydrochar can overcome this shortcoming. Herein, polyethyleneimine-modified hydrochar (PEI-HC) was synthesized from hydrothermal carbonization (HTC) of methyl acrylate and bamboo after addition of initiator ammonium persulfate, and then modified by polyethyleneimine (PEI), which was used to treat Cr(VI).