# Steam Explosion-Based Method for the Extraction of Cellulose and Lignin from Rice Straw Waste
## 2 Materials and Methods  
### Materials  
Rice straw was sourced from the Albufera of Valencia, a renowned wetland and rice growing area in Spain. This material was generously provided by Unio Llauradoros i Ramaders (Valencia, Spain), a prominent organisation representing agricultural professionals in the region, known for its commitment to sustainable farming practices. The Albufera of Valencia is well known for its extensive rice fields, and the rice straw used in this study is a byproduct of these fields, commonly available post-harvest. To illustrate the physical characteristics of the rice straw, Figure 1 shows both its state when harvested and before processing.  
For the chemical treatment of the rice straw, several reagents were employed. Sodium hydroxide (NaOH), hydrogen peroxide (H\({}_{2}\)O\({}_{2}\)), acetic acid (CH\({}_{3}\)COOH), potassium hydroxide (KOH), and sodium hypochlorite (NaClO) were all procured from Merck KGaA (Darmstadt, Germany). Additionally, carbon dioxide (CO\({}_{2}\)) was used in the form of a compressed gas, sourced from Sociedad Espanola de Carburos Metalicos, S.A. (Barcelona, Spain), for its application in the steam explosion experiments, although it was not consistently used across all experimental procedures. All chemicals were used as received,  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Biomass** & **Extraction Method** & **Conditions** & **Yield** & **Strategic Advancements** & **Reference** \\ \hline \multirow{4}{*}{Olive stones} & \multirow{4}{*}{Acid pretreatment, steam explosion, and enzymatic hydrolysis} & Acid pretreatment and steam explosion, various temperatures (120–200 \({}^{\circ}\)C) and durations; enzyme specificity adjusted for biomass & Yields of 83\% total sugar recovery from raw material, with specific yields for xylose (71% from acid pretreatment) & Integrated approach utilising steam explosion in conjunction with acid pretreatment for enhanced biomass fractionation, applicable to cellulose extraction processes & \\  & & & & & \\  & & & & & \\  & & & & & \\  & & & & & \\  & & & & & \\ \hline \multirow{4}{*}{Rice straw} & \multirow{4}{*}{Steam explosion followed by ionic liquid treatment, organosololol, and biological efficiency} & \multirow{4}{*}{AMIMCI ionic efficiency} & \multirow{4}{*}{Cellulose purity up to 64.80\% and yield of 30.73\% for bleached cellulose using AMIMCI} & Introduced environmentally backgrounds for cellulose activation from straw, showcasing the potential of rice straw cellulose in enhancing the mechanical properties of composites; \\  & & & & & \\  & & & & & \\  & & & & & \\  & & & & & \\  & & & & & \\  & & & & & \\  & & & & & \\ \hline \multirow{4}{*}{Agricultural residues, wood biomass, and aquatic plants} & \multirow{4}{*}{Steam explosion, nectar, at/alkaline treatments, enzymatic hydrolysis, and ionic liquid} & \multirow{4}{*}{Optimal methods specific pH for chemical treatments, repair of chemical treatments, repair of enzymatic administration} & \multirow{4}{*}{Optimal methods specific pH for cellulose purity (\(>\)90\%) and treatment methods; significant lignin removal by biomass characteristics and end-use applications} & \\  & & & & & \\ \cline{1-1}  & & & & \\ \cline{1-1}  & & & & & \\ \cline{1-1}  & & & & & \\ \hline \hline \end{tabular}
\end{table}
Table 1: _Cont._without further purification. The solutions and mixtures were prepared using distilled Milli-Q water to ensure the consistency and reliability of the experimental results.