Abstract:

The present study optimized the ultrasonic-assisted extraction of cellulose from pomelo peel by the combined use
of single factor method and response surface methodology (RSM). In the extraction process, pomelo peel was ultrasonically
treated with (NaOH) at a certain temperature for the removal of hemicelluloses, followed by further removal of lignin
and simultaneous decolorization with hydrogen peroxide. The influences of sodium hydroxide concentration, extraction
temperature, ultrasonication time and hydrogen peroxide concentration, as well as interactions among the former three
variables on the cellulose content (i.e., purity) of pomelo peel extract were investigated. The results indicated that the
cellulose content of pomelo peel extract was affected in decreasing order by the following factors: extraction temperature >
sodium hydroxide concentration > ultrasonication time. Through response surface methodology, the process conditions
for hemicelluloses removal were optimized as follows: NaOH concentration 9.4 g/100 mL, temperature 84 ℃ and
ultrasonication time 77 min. Under these conditions, the purity of cellulose extracted from pomelo peel was 63.12%.

Key words: pomelo peel, cellulose, ultrasonic-assisted extraction, response surface methodology