Preparation of carboxymethyl cellulose (CMC) derived from palm fiber waste: Effect of ozone pretreatment on CMC properties

Carboxymethyl cellulose (CMC) was prepared using cellulose extracted from palm fiber (CPF). The effect of ozone pretreatment on the CMC properties degree of substitution (DS) and viscosity was investigated. After treatment of CPF with ozone, CMC was prepared by alkalization followed by etherification using sodium hydroxide (NaOH) and sodium monochloroacetic acid (NaMCA) in an alcoholic medium. The DS of CMC increased with increased ozone pretreatment time and with increased amounts of NaOH and NaMCA reagents. The CMC solubility increased with increasing DS. Therefore, the solubility increased with ozone pretreatment time. The favored treatment conditions were ozone pretreatment for 3 h, followed by the addition of 10 mL of 30% NaOH and 38.6 mM of NaMCA. Under these conditions, the DS, purity, and solubility were 1.05, 79.6%, and 94.6%, respectively. The viscosity of CMC prepared using cellulose treated with ozone decreased with increasing ozone pretreatment time, which was caused by the reduced degree of polymerization. Therefore, use of ozone pretreatment for CMC preparation is an effective method for controlling CMC properties.