Quantachrome

After the main structure had been, it was scrutinized employing a Fourier transform infrared (FT-IR) spectrometer (PerkinElmer, Waltham, MA, USA) in the range of 380–4000 cm⁻¹. This was performed by incorporating the sample with the KBr disk (5% of the mixture). In order to characterize the composition, the prepared PASACs were coated with gold for analyses with scanning electron microscope (SEM, FEI Quanta FEG 250, Oregon, USA). Nitrogen adsorption, as assessed with the Brunauer–Emmett–Teller (BET) method, was used as a measure for the determination of the resulting surface area using Quantachrome (Nova, 2000e Quantachrome Instruments, USA). Additionally, the pore diameter was obtained by using the Barrett–Joyner–Halenda (BJH) method, and carbon (C), hydrogen (H), nitrogen (N), and oxygen were assessed in the samples. The elemental analyzer (Eurovector, EA3000-Single, Pavia, Italy) was used to determine the (O) content. A thermal gravimetric analyzer (TGA temperatures between 50 and 850 °C losses) was used to determine the thermal degradation ranges under continuous N₂ flow at a heating rate of 15 °C/min.

The CO₂ adsorption experiments were carried out in dynamic conditions in a flow system. Prior to the start of the adsorption experiments, the adsorbent sample (0.40 g) was dried at 150 °C for 1 h. The experiments for CO₂ adsorption were performed at 25 °C with 3 vol.% CO₂/N₂ at a flow rate of 30 mL/min. The samples were pressed and crushed in order to obtain materials with particle sizes of 0.2–0.8 mm. Additionally, the experiments for CO₂ and water vapor adsorption (3 vol.% CO₂ plus 1 vol.% water vapor) were performed at a 30 mL/min flow rate. The adsorption capacities of the materials were calculated based on the amounts of adsorbed CO₂ and water vapor by using online GC analysis (gas chromatograph NEXIS GC-2030 ATF (Shimadzu, Kyoto, Japan) with a 25 m PLOT Q capillary column).
The CO₂ adsorption measurements under static conditions were determined at 0 °C, 25 °C, and 50 °C with an AUTOSORB iQ-MP-AG (Anton Paar GmbH, Graz, Austria) surface area and pore size analyzer (from Quantachrome, Anton Paar GmbH, Graz, Austria). The Quantachrome software was used for the transformation of the primary adsorption data.

The characterization of the adsorbent was carried out before and after adsorption. Observing its surface morphology was investigated using a scanning electron microscope (SEM; Hitachi TM-1000, Tokyo, Japan) with a gold coating for 30 s. The volume and density of the pieces were determined by a gas pycnometer (Quantachrome, Ultrapyc 1200e Anton Paar, Graz, Austria). For the verification of chemical identity on the aerogel, a Fourier Transform Infrared Radiation (FTIR) spectroscopy was performed; using attenuated total reflection mode (ATR). These measures were taken at room temperature using an IR spectrophotometer (Alpha II Bruker, Billerica, MA, USA), analyzed in the range of 400–4000 cm⁻¹.