# A New Route for Low Pressure and Temperature
## Materials and Methods
### Catalytic Tests  
Catalytic tests in phenol wet air oxidation were conducted in a glass semi-batch apparatus. The reaction system, magnetically stirred and temperature-controlled, was equipped with a heating jacket stage. Gas feeding was monitored and controlled by a gas flow controller. In this set of experiments, pure air (SOL 99.999%) and pure nitrogen (SOL 99.999%) were used. In a typical run, 10 mL of aqueous phenol solution at known concentration were placed into the reactor, following catalyst loading. The temperature was increased, up to the operating condition, under N\({}_{2}\) gas to avoid uncontrolled degradation phenomena. When the set point was reached, gas feed changed to compressed air, allowing the gas to bubble throughout the liquid batch. The constant gas flow of 4.6 NL/h and stirring were maintained during the experiment. Samples were taken at various time intervals, and phenol concentrations or UV-vis spectra were acquired. Operating conditions were summarized in Table 1. Moreover, before all the catalytic tests, the resins (0.4 g/L), loaded and not with the catalyst, were saturated with phenol in the absence of airflow, at 95 \({}^{\circ}\)C, and in a 4000 mg/L solution of phenol, waiting for equilibrium and then taken for the tests performance.  
The CO\({}_{2}\) evolved was monitored with a SIEMENS Utramar 22 analyzer (Siemens, Erlangen, Germany). The CO\({}_{2}\) of the liquid phase in equilibrium with the gas phase was obtained from specific equilibrium studies at the pressure and temperature of the tests.  
Gas-chromatographic analyses were performed in a GC Focus Series (Thermo Scientific) coupled with a single quadrupole ISQ (Thermo Scientific, Waltham, MA, USA) mass spectrometer. The method details are summarized in Table 2.  
Acylation of the reaction solutions was performed for analysis.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Parameters** & **Value** \\ \hline Temperature (\({}^{\circ}\)C) & 95 \\ Pressure (MPa) & 0.3 \\ Air Gas Flow (NL/h) & 4.6 \\ Phenol concentration (mg/L) & 4000–1000 \\ Catalyst concentration (g/L) & 0.4 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Operating conditions.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**GC-MS Configuration** \\ \hline \hline  & **Injector** \\ Inlet temperature & 230 \({}^{\circ}\)C \\ Sample size & 1 \(\mu\)L \\ Split ratio & 12 \\
**Column temperature program** \\ Initial temperature & 50 \({}^{\circ}\)C for 1 min \\ Rate 1 & 7.0 \({}^{\circ}\)C/min to 180 \({}^{\circ}\)C for 1 min \\ Rate 2 & 10 \({}^{\circ}\)C/min to 300 \({}^{\circ}\)C for 1 min \\  & **Detector** \\ Type & Mass spectrometer \\ Interface temperature & 230 \({}^{\circ}\)C \\  & **Column** \\ Type & HP-5 (0.25 \(\mu\)m \(\times\) 0.25 mm \(\times\) 30 m) \\ Flow rate & 1 mL/min \\  & **Other** \\ Gas Flow & Helium \\ Electron ionization (EI) & 70 eV \\ Scan range & 35 \(\div\) 450 amu \\ Scan rate & 1.80 scans/s \\ \hline \hline \end{tabular}
\end{table}
Table 2: GC-MS configuration.  
Total organic carbon values were analyzed in a 1020A TOC analyzer, the removal ratio \(\Delta\)(TOC)% was expressed as in the equation  
\[\Delta\text{(TOC)}\%=\text{(TOC}_{0}-\text{TOC}_{1})/\text{TOC}_{0}\times 100 \tag{1}\]  
Mineralization degree was evaluated through the equation  
\[\text{M}\%=\text{[CO}_{2}]_{\text{tot(t)}}/\text{TOC}_{0}\times 100 \tag{2}\]  
The carbon contents in catalysts after tests were evaluated by temperature-programmed oxidation (TPO) using a 1% O2/He mixture (14 mL/min) in the range 30-700 \({}^{\circ}\)C temperature range (heating rate: 70 \({}^{\circ}\)C/min).  
Turn over frequency (TOF) values were evaluated through the equation  
\[\text{TOF}=\text{C}_{\text{PheR}}/\text{C}_{\text{cat}}\times\text{t} \tag{3}\]  
where C\({}_{\text{PheR}}\) is the concentration of phenol removed; C\({}_{\text{cat}}\) is the concentration of catalyst; and, t is the reaction time.