Accepted Manuscript Molecular mechanism of anionic dyes adsorption on cationized

ACCEPTED MANUSCRIPT
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activated carbons from rice husks cellulose and tested their dye adsorption 
performance [13]. According to the reports, rice husks are reported to contain 33% 
cellulose, 26% hemicellulose and 7% lignin [14]. In contrast, the main organic 
components of cellulose from rice husks should been utilized in many materials field 
through the purification and modification method for producing cellulose fibers and 
cellulose-based modified materials. 
As for pure rice husks cellulose, the molecules of cellulose itself have a large 
number of hydroxyl groups, resulting in a certain degree of adsorption capacity, so 
they can be directly used for the purification of dyes, oils and fats. However, if 
cellulose is directly used as an adsorbent without physical or chemical modification, 
not only the adsorption capacity may be very low, but also the selectivity is not good.
In order to improve the adsorption capacity of the original cellulose, many researchers 
have prepared cellulose adsorbents by the modification of cellulose, such as 
esterification, etherification, graft copolymerization, and so on. In the purification of 
dye wastewater, most of the dyes in the water body are positive or negative. The 
adsorption mechanism is often caused by the electrostatic forces, van der Waals forces, 
hydrogen bonding and other actions that are induced between the adsorbent and the 
pollutant molecules [15]. In order to achieve the purpose of purifying dye wastewater, 
the adsorbent itself should have a certain charge, as well as a linear structure of the 
polymer, to satisfy the conditions for the neutralization of adsorption and the 
formation of adsorption bridging.
Cationized cellulose is a derivative of cellulose, 
cationic functional groups are grafted onto its active hydroxyl group structure to 
prepare this type of modified cellulose. Cationized cellulose exhibits cationic 
properties at different pH values, which is favorable for the adsorption of anionic 
contaminants in water under electrostatic attraction. Moreover, cationized cellulose is 
a linear polymer compound that has the potential to form adsorption bridge action and 
facilitates the removal of pollutants from wastewater by adsorption. 
Quaternary ammonium salts are a relatively common cationic compound, which 
can interact with negatively charged materials on the surface. At present, 
trimethylamine [16], 3-chloro-2-hydroxypropyltrimethylammonium chloride [17] and 

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