Autosorb iq2

The samples were measured by PXRD (PXRD, Bruker, D8). All the COFs were recorded in the 2θ range between 2˚ and 40˚. The radiation was Cu Kα (λ = 1.54 Å), and the data collection was carried out using an Aluminum holder at a scan speed of 1° min⁻¹ and a step size of 0.02˚. Fourier transform infrared (FT-IR) spectra were collected using a thermofisher Nicolet 6700 spectrometer.
TEM images were collected using FEI Tecnai G2 F20 S-Twin (acceleration voltage: 200 kV). SEM images were collected using Zeiss Gemini SEM500. The SEM samples were prepared by evaporating a drop of alcohol with COFs on a clean Si/SiO₂ wafer. OM and cross-polarized OM images were collected using a polarized OM (Leica DM2500P).
The N₂ adsorption-desorption experiments were conducted on an Autosorb iQ₂ (Anton Paar) surface area analyser. The os-COF_TP-Py sample was washed in THF by Soxhlet’s extraction for 3 days, dried in vacuum for 12 h, and degassed at 120 °C for 12 h before the measurement. The sc-COF_TP-Py sample was purified by liquid CO₂ for 5 times, kept in sc-CO₂ (40 °C 8 MPa) for one hour (Samdri®-PVT-3D, Tousimis) and degassed at 0.13 MPa min⁻¹ before the measurements^{49 (link)}. N₂ isotherms were recorded at 77 K by using ultra-high purity N2 (99.999% purity). The surface area was determined using Brunauer-Emmett-Teller (BET) adsorption model.

To determine the adsorption isotherms of CO₂ at 273 K and 1 Bar, a commercial semi-automatic sortometer Autosorb IQ2 (Quantachrome Instruments) was used, simultaneously a calorimeter coupled to the sortometer was used to measure the energy changes involved in each point of the isotherm, 100 mg of activated carbon were used, the samples were degassed at 423 K for 24 h, until the system reached a pressure between 10⁻⁵ and 10⁻⁶ Bar Simultaneously, the calorimetric signal was allowed to stabilize and injections of the adsorbate were carried out, waiting for the time necessary to reach the equilibrium between the system components, so the volumes of gas adsorbed and the heat involved in each injection were simultaneously recorded.

The SSA was analyzed on composite heavy soil fractions for each mineralogical combination. Organic matter was removed from the samples by treatment with 6% NaOCl^{31 (link)}. The SSA of freeze-dried and homogenized samples was analyzed in duplicates based on a 10-point adsorption of N₂ at 77 K in the relative pressure range of 0.05–0.30^{66 (link)} with an Autosorb IQ2 instrument (Quantachrome Instruments, Boynton Beach, FL 33,426). Before measurement, samples were degassed at 60 °C until the pressure increase in the analysis cell was < 20 mTorr min^–1. The SSA was corrected for OM remaining after NaOCl treatment^{67 (link)}.

Metaldehyde was analysed by gas chromatography (Perkin Elmer precisely Clarus 500) with mass spectrometry (GC-MS), as recommended by the UK Environment Agency.³ Sample solutions containing metaldehyde were taken and analysed using the same solid phase extraction (SPE) and the GC-MS methods described in our previous research with a detection limit of metaldehyde from 1 to 5 μg L⁻¹.^{8 (link)} The concentration of samples containing HA were determined by CamSpec M550 Double Beam Scanning UV-Vis Spectrophotometer at 254 nm. Sample solutions from binary adsorption tests containing both metaldehyde and HA were analysed by both methods to determine the concentrations of metaldehyde and HA separately. The presence of HA does not affect the detection of metaldehyde in the binary adsorption system and vice versa. pH values were measured by the pH meter SevenMulti, Mettler Toledo. Brunauer–Emmett–Teller (BET) specific surface area analysis of PAC was done by Autosorb-iQ2 automated gas sorption analyser (Quantachrome Instruments) via adsorption and desorption of nitrogen gas at 77 K after PAC sample being degassed at temperature of 180 °C for 24 hours. Scanning Electron Microscope (SEM) images of PAC were taken by JSM-6701F Field Emission Scanning Electron Microscope (JEOL) at 10 kV under secondary electron imaging mode (SEI).