Department of Chemical and Materials Engineering, Faculty of Engineering, The University of Auckland, Auckland, New Zealand.
Department of Anaesthesia, Middlemore Hospital, Counties Manukau Health, Otahuhu, Auckland, New Zealand.
Chemosphere. 2020 Dec;260:127496. doi: 10.1016/j.chemosphere.2020.127496. Epub 2020 Jul 6.
Activated carbons have been reported to be useful for adsorptive removal of the volatile anaesthetic sevoflurane from a vapour stream. The surface functionalities on activated carbons could be modified through aqueous oxidation using oxidising solutions to enhance the sevoflurane adsorption. In this study, an attempt to oxidise the surface of a commercial activated carbon to improve its adsorption capacity for sevoflurane was conducted using 6 mol/L nitric acid, 2 mol/L ammonium persulfate, and 30 wt per cent (wt%) of hydrogen peroxide (HO). The adsorption tests at fixed conditions (bed depth: 10 cm, inlet concentration: 528 mg/L, and flow rate: 3 L/min) revealed that HO oxidation gave desirable sevoflurane adsorption (0.510 ± 0.005 mg/m). A parametric study was conducted with HO to investigate the effect of oxidation conditions to the changes in surface oxygen functionalities by varying the concentration, oxidation duration, and temperature, and the Conductor-like Screening Model for Real Solvents (COSMO-RS) was applied to predict the interactions between oxygen functionalities and sevoflurane. The HO oxidation incorporated varying degrees of both surface oxygen functionalities with hydrogen bond (HB) acceptor and HB donor characters under the studied conditions. Oxidised samples with enriched oxygen functionalities with HB acceptor character and fewer HB donor character exhibited better adsorption capacity for sevoflurane. The presence of a high amount of oxygen functional groups with HB donor character adversely affected the sevoflurane adsorption despite the enrichment of oxygen functional groups with HB acceptor character that have a higher tendency to adsorb sevoflurane.
活性炭已被报道可用于从气流中吸附去除挥发性麻醉剂七氟醚。通过使用氧化溶液对活性炭的表面官能团进行水氧化改性，可以增强对七氟醚的吸附。在这项研究中，尝试使用 6 mol/L 硝酸、2 mol/L 过硫酸铵和 30 wt%（wt%）过氧化氢（HO）氧化商业活性炭的表面以提高其对七氟醚的吸附能力。在固定条件（床层深度：10 cm，入口浓度：528 mg/L，流速：3 L/min）下进行的吸附测试表明，HO 氧化可获得理想的七氟醚吸附（0.510±0.005 mg/m）。进行了 HO 的参数研究，以通过改变浓度、氧化时间和温度来研究氧化条件对表面氧官能团变化的影响，并应用导体相似屏蔽模型用于真实溶剂（COSMO-RS）来预测氧官能团与七氟醚之间的相互作用。在研究条件下，HO 氧化会产生具有氢键 (HB) 接受体和 HB 供体特性的不同程度的表面氧官能团。具有 HB 接受体特性和较少 HB 供体特性的富氧官能团氧化样品表现出更好的七氟醚吸附能力。尽管具有 HB 接受体特性的氧官能团的富集会增加吸附七氟醚的趋势，但具有 HB 供体特性的大量氧官能团的存在会对七氟醚的吸附产生不利影响。
