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[Display omitted] • A 3D network structure carbon aerogel of PPD-Cu/CA for deep removal of COS from natural gas. • Para-phenylenediamine doping improves the pore structure of the adsorbent and introduces basic pyridine nitrogen. • The introduction of p-phenylenediamine increases the number of moderate basic sites on the adsorbent. • The adsorbent exhibits excellent high space velocity resistance and water resistance. • The COS adsorption capacity of the optimized PPD-Cu/CA adsorbent can reach 18.6 mg/g at 40 °C. For the purpose of overcoming the difficulty of low removal rate of COS at low temperatures, N-doped copper oxide-supported carbon aerogels were prepared with sodium alginate as a carbon source for deep removal of COS (about 20 ppm) from natural gas. By exploring the effects of different nitrogen sources (urea, melamine and p-phenylenediamine), carbon–nitrogen ratio and carbonization temperature, p-phenylenediamine-doped copper oxide-loaded carbon aerogels (PPD-Cu/CA) with both excellent catalytic hydrolysis of COS and adsorption were prepared. The COS adsorption capacity of optimized PPD-Cu/CA was 18.6 mg·g−1 with 0.94 %Vol of water content at 40 °C, meanwhile, the COS removal efficiency at 40,000 and 70,000 mL·g−1·h−1 could reach 100 % and 94.6 %, respectively, showing excellent high space velocity resistance. Combined with characterization and experimental results, the introduction of p-phenylenediamine enriched the pore structure of the carbon carrier, increased the neutral base site, and played a positive role in the adsorption and hydrolysis of COS. This study provides a new insight into the removal of carbonyl sulfur from natural gas. [ABSTRACT FROM AUTHOR]

• At low temperature the 5%K 2 O-Cu/CA achieved good COS conversion performance. • The surface hydroxyl group is enriched by K loading. • The escaped H 2 S could be adsorbed to be S2- and SO 4 2- on 5 %K 2 O-Cu/CA. • The adsorbent could be regenerated by N 2 regeneration process. COS in natural gas is difficult to be effectively removed at room temperature. Catalytic hydrolysis is a promising method, however, the discrepancy of catalytic active site as well as deactivation factors are the restricting factors. In this paper, the CuO load and alkali metal modification was successfully prepared on carbon aerogel with more mesoporous structure(5 %K 2 O-Cu/CA). The doping of K could improve the pore structure of the sample and is more conducive to the storage of sulfate, obtaining good anti-poisoning properties. Meanwhile, the K load achieved enriched surface hydroxyl groups, which played an important role in COS conversion, and provided enough electronic electron transfers to accelerate the H 2 O dissociation, producing more hydroxyl groups. Then the adsorbed COS could be efficiently captured by the increasing number of weak basic sites at low temperature. Furthermore, after COS transformation the escaped H 2 S could be subsequently adsorbed on 5 %K 2 O-Cu/CA surface and converted to be S2- and SO 4 2- on CuO surface. Finally, the adsorbent capacity and deactivation were studied, and the N 2 regeneration method owns the higher sulfur capacity of 6.01 mg/g with a COS removal efficiency of 100 % for the first time. [ABSTRACT FROM AUTHOR]