Sodium Chloride interaction with solvated and crystalline cellulose : sodium ion affects the tetramer and fibril in aqueous solution

摘要

Inorganic salts are a natural component of biomass which have a significanteffect on the product yields from a variety of biomass conversion processes.Understanding their effect on biomass at the microscopic level can helpdiscover their mechanistic role. We present a study of the effect of aqueoussodium chloride (NaCl) on the largest component of biomass, cellulose, focusedon the thermodynamic and structural effect of a sodium ion on the cellulosetetramer, and fibril. Replica exchange molecular dynamics simulations of acellulose tetramer reveal a number of preferred cellulose-Na contacts andbridging positions. Large scale MD simulations on a model cellulose fibril findthat Na+ perturbs the hydroxymethyl rotational state population andconsequently disrupts the "native" hydrogen bonding network.