## 2 Results and Discussion
### Reactivities of Model Bio-Oil Components
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Catalyst**} & \multicolumn{3}{c}{**Selectivity (\%)**} \\ \cline{2-4}  & \(\mathbf{O}\)**-alkylates** & \(\mathbf{C}\)**-alkylates** & **Di-\(\mathbf{C}\)-alkylates** \\ \hline Amberlyst 15 & 5.5 & 86.0 & 8.5 \\ Cs\({}_{2.5}\)/K10 & 3.2 & 65.9 & 30.9 \\ Amberlyst 36 & 8.0 & 86.3 & 5.7 \\ Dowex50 WX2 & 33.5 & 63.2 & 3.3 \\ SSA & 37.2 & 34.4 & 28.4 \\ \hline \hline \end{tabular}  
* Reaction conditions: (solid catalyst, 0.15 g; time: 3 h; 1-octene: phenol (mmol) = 10:10.  
\end{table} 
Table 4: Product distributions of 1-octene reaction with neat phenol over different catalysts at 120 \({}^{\circ}\)C \({}^{\text{a}}\). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Catalyst**} & \multicolumn{3}{c}{**Selectivity (\%)**} & \multicolumn{3}{c}{\({}^{\text{b}}\)**Yield (\%)**} \\ \cline{2-5}  & \(\mathbf{O}\)**-alkylates** & \(\mathbf{C}\)**-alkylates** & **Di-\(\mathbf{C}\)-alkylates** & **Octanols** & **Dioctyl ethers** \\ \hline Amberlyst 15 & 82.5 & 16.0 & 1.5 & 5.4 & 0.2 \\ Cs\({}_{2.5}\)/K10 & 75.9 & 20.8 & 3.3 & 6.7 & 0.4 \\ Amberlyst 36 & 73.7 & 25.0 & 1.4 & 0.7 & 0.2 \\ Dowex50 WX2 & 84.5 & 12.5 & 3.0 & 4.7 & 1.7 \\ SSA & 75.1 & 19.5 & 5.4 & 3.4 & 1.7 \\ \hline \hline \end{tabular}  
* Reaction conditions: (solid catalyst, 0.15 g; time: 3 h; 1-octene: phenol: water (mmol) = 10:10.  
\({}^{\text{b}}\) GC area% of involved compounds _versus_ the sum of the GC area% of all products that remained after the reaction.  
\end{table} 
Table 5: Product distributions from 1-octene reactions in phenol/water at 120 \({}^{\circ}\)C \({}^{\text{a}}\). 1-octene (Scheme 3), generating three groups of improved fuel components in one operation without water generation. Trace amount of phenyl acetate were formed. The phenyl acetate yield decreased with increasing temperatures from 60 to 100 \({}^{\circ}\)C [17]. Both SSA and DX2 show higher catalytic activity than other three catalysts based on related phenol conversions and octyl acetates yields. **Scheme 2. ** Acid-catalyzed reactions of water with 1-octene. **Scheme 3. ** Acid-catalyzed reactions of acetic acid as a model carboxylic acid with 1-octene. Bio-oil contains a large number of primary and secondary aliphatic hydroxyl groups from cellulose and hemicellulose pyrolysis. Table 7 provides the phenol conversions and butyl octyl ethers yields of 1-octene reactions with phenol/water/1-butanol mixtures over Dowex50 WX2, SSA, Amberlyst15 and Cs\({}_{2.5}\)/K10, respectively. Except for the reactions mentioned above, butyl octyl ethers were generated by either 1-butanol etherification with octanols or 1-butanol addition across octenes (Scheme 4). SSA gave the highest phenol conversion (69.2%), illustrating it had the highest catalytic activity. Cs\({}_{2.5}\)/K10, which gave a phenol conversion of only 6.9%, lost almost all its activity during the reaction. Multifunctional compounds such as hydroxyacetone or hydroxyethanal in bio-oil can oligomerize and polymerize. Aldol condensation reactions accelerate bio-oil aging [7]. Table 8 summarizes the effect of the presence of hydroxyacetone upon 1-octene reactions with phenol/water over Cs\({}_{2.5}\)/K10 \begin{table}
\begin{tabular}{l c c} \hline \hline
**Catalyst** & **Phenol Conversion (\%)** & \({}^{\text{b}}\)**Yield (\%) Octyl acetates** \\ \hline Amberlyst 15 & 5.6 & 0.6 \\ Cs\({}_{2.5}\)/K10 & 2.3 & 0.4 \\ Amberlyst 36 & 6.5 & 1.0 \\ Dowex50 WX2 & 63.1 & 4.3 \\ SSA & 67.2 & 9.4 \\ \hline \hline \end{tabular} \({}^{\text{a}}\)Reaction conditions: (solid catalyst, 0.15 g; time: 3 h; 1-octene: phenol: water: acetic acid (mmol) = 10:10:3.0;  
\({}^{\text{b}}\)GC area% of involved compounds _versus_ the sum of the GC area% of all products remained after the reaction.  
\end{table} 
Table 6: Phenol conversions and octyl acetates yield of 1-octene reactions with phenol/water/acetic acid over different catalysts at 120 \({}^{\circ}\)C \({}^{\text{a}}\). and SSA catalysts. A good phenol conversion (64.0%) was obtained over SSA.