This study aim is to propose operational conditions for the dilute acid pretreatment of rice straw and to
explore the effect of the structural properties of the solid residues on the enzymatic hydrolysis. A maximal
sugar yield of 83% was achieved when the rice straw was pretreated with 1% (w/w) sulfuric acid with
a reaction time of 1–5 min at 160 C or 180 C, followed by enzymatic hydrolysis. The completely release
of sugar (xylose and glucose) increased the pore volume of the pretreated solid residues resulted in an
efficiency of 70% for the enzymatic hydrolysis. The extra pore volume was generated by the release of
acid-soluble lignin and this resulted in the enzymatic hydrolysis being enhanced by nearly 10%. The
increase in the crystallinity index of the pretreated rice straw was limited. These results were consistent
with those from the Fourier transformer infrared (FTIR) analysis.