Separation and recovery of cellulose from Zoysia japonica by 1-allyl-3-methylimidazolium chloride

► Water pretreatment is used at 121 °C to make structure more porous. ► Cellulose extraction rate is 71% and the purity can be as high as 99%. ► The mechanism of water pretreatment and ionic liquid dissolution is studied. ► AMIMCl can only recover cellulose meanwhile the crystallinity decreased.