Decarbonisation Technology May 2026 Issue

regeneration temperature, as well as their availability and low production costs ( Yihang et al., 2025 ). Other prospective adsorbent systems involve nanostructured materials, including metal-organic frameworks (MOFs), covalent organic frameworks (COFs), zeolites, porous carbons, and layered double hydroxides (LDHs) ( Simari, 2025 ). However, so far, no single material dominates; the best approach depends on context and integration with renewable energy sources, and any single approach will likely be unable to meet all geographical requirements ( Wenzel et al., 2025 ). With growing computational power becoming available, AI systems are even employed in virtual material screening ( Sriram et al., 2025 ). This stresses the importance of fast, reproducible test equipment to provide reliable data for both practical empirical and in-silico research. employed for the screening of adsorbents in a controlled laboratory setting. The protocol focused on the systematic evaluation of CO 2 adsorption capacities under varying conditions, utilising an automated system for precision, repeatability, and efficiency. CO2 amounts were quantified during both the adsorption and desorption phases using temperature- programmed desorption for CO 2 release. The procedure described is a first attempt at a standardised method to assess the performance of CO 2 capture materials in a broader material screening. Such a protocol could augment current approaches in modelling and machine learning by providing real experimental feedback. Experimental This section outlines the methodology Materials and methods Two methods were used to generate particles of suitable size. The first method involved the modification of commercially available shaped supports: alumina beads (Saint‑Gobain NorPro SA6175, 1 mm, referred to as ‘Al 2 O 3 I’; SA62125, 2 mm, referred to as ‘Al 2 O 3 II’). The second method involved functionalising a high‑surface‑area powder (Sasol Puralox TH100/150, d₅₀ ≈ 35 µm, referred to as ‘Al 2 O 3 powder’). After modification, the powder

was pressed into tablets, crushed, and sieved to obtain a size fraction of 500-1,000 µm. Incipient wetness impregnation : For the preparation, 10 g of dry support (pre‑dried at 120°C overnight) were loaded into a 100 mm porcelain dish. Polyethyleneimine (PEI, Sigma- Aldrich, branched, Mw≈800 Da, Mn≈600 Da, PDI = 1.33) was dissolved in anhydrous ethanol (ThermoFisher Scientific, extra dry Acroseal), with the solvent volume calculated from the support’s pore volume to achieve incipient wetness impregnation. The PEI solution was added dropwise while stirring to ensure uniform coating. The impregnated material was sealed and soaked at room temperature for three hours, then the ethanol was evaporated in a fume hood for one hour. The sample was dried in a furnace at 100°C for six hours (heating rate = 2°C min - ¹) under an air flow, transferred while warm to a desiccator, and stored over silica gel until testing. Sample characterisation : To confirm PEI loading, samples underwent thermogravimetric analysis (TGA): heated to 650°C in air at 1°C min - ¹ with a one‑hour hold at 100°C to remove moisture. Unmodified supports were analysed similarly; the net mass loss between 100°C and 650°C (impregnated minus bare) equalled the grafted amine amount. In addition, specific surface areas were measured by nitrogen gas (N₂) physisorption (TriStar II 3020, Micromeritics) using the Brunauer-Emmett-Teller (BET) method. Performance testing Test unit: For the experiments, a setup developed in-house was employed (see Figure 1 ). The test rig was equipped with a 12-fold carousel sample exchanger, which allowed unattended 24/7 operation and screening of several samples without human interaction. For testing, each adsorbent was loaded into an 8 mm ID stainless‑steel reactor and mounted on the carousel. Individual samples were selected by a rotating motion and lifted into the isothermal zone of the heater. Graphite gaskets ensured gas‑tight sealing. After each exchange, the system automatically verified integrity by pressurising the reactor section and confirming zero pressure loss.