{"title":"Fabrication of a cost-effective metal oxide-based adsorbent from industrial waste slag for efficient CO2 separation under flue gas conditions","authors":"","doi":"10.1016/j.jcou.2024.102930","DOIUrl":null,"url":null,"abstract":"<div><p>Efficient and affordable adsorbents for CO<sub>2</sub> capture are essential in implementing carbon capture technology to mitigate the negative impact of greenhouse gas emissions. This study focuses on synthesizing new nanoporous adsorbents from industrial waste slag using a simple and cost-effective coprecipitation method. In this method, raw slag was milled for 48 h and used as a benchmark for comparing two newly synthesized adsorbents. Selectivity and pure gas isotherm experiments were conducted for all adsorbents in the 25–65°C temperature range and under harsh industrial conditions of 65°C and 15 % CO<sub>2</sub>. This study utilized the response surface methodology (RSM) to optimize the CO<sub>2</sub> adsorption parameters. Specifically, the optimized adsorption conditions were determined for the 15/85 % CO<sub>2</sub>/N<sub>2</sub> condition, and the optimal values for pressure and temperature were found to be 5 bar and 45°C, resulting in CO<sub>2</sub>/N<sub>2</sub> selectivity of 5.65. The NH<sub>3</sub>-slag adsorbent was identified as the superior choice based on its selectivity and maximum adsorption capacity. The maximum adsorption capacity and cyclic efficiency were determined to be 4.15 mmol/g and 98.1 %, respectively, at a temperature, pressure, and composition of 45°C, 5 bar, and 15 % CO<sub>2</sub>. Isotherm and thermodynamic models were employed to further investigate the adsorption process. The isotherm results indicated that the adsorption of CO<sub>2</sub> by adsorbents occurred heterogeneously in patch-wise sites. Meanwhile, the thermodynamic parameters showed that the process was exothermic and spontaneous, with ΔH° falling below 20 (kJ/mol), showing physisorption phenomena.</p></div>","PeriodicalId":350,"journal":{"name":"Journal of CO2 Utilization","volume":null,"pages":null},"PeriodicalIF":7.2000,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2212982024002658/pdfft?md5=013f18d4128137433bf6a1ea98ea02e0&pid=1-s2.0-S2212982024002658-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of CO2 Utilization","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2212982024002658","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Efficient and affordable adsorbents for CO2 capture are essential in implementing carbon capture technology to mitigate the negative impact of greenhouse gas emissions. This study focuses on synthesizing new nanoporous adsorbents from industrial waste slag using a simple and cost-effective coprecipitation method. In this method, raw slag was milled for 48 h and used as a benchmark for comparing two newly synthesized adsorbents. Selectivity and pure gas isotherm experiments were conducted for all adsorbents in the 25–65°C temperature range and under harsh industrial conditions of 65°C and 15 % CO2. This study utilized the response surface methodology (RSM) to optimize the CO2 adsorption parameters. Specifically, the optimized adsorption conditions were determined for the 15/85 % CO2/N2 condition, and the optimal values for pressure and temperature were found to be 5 bar and 45°C, resulting in CO2/N2 selectivity of 5.65. The NH3-slag adsorbent was identified as the superior choice based on its selectivity and maximum adsorption capacity. The maximum adsorption capacity and cyclic efficiency were determined to be 4.15 mmol/g and 98.1 %, respectively, at a temperature, pressure, and composition of 45°C, 5 bar, and 15 % CO2. Isotherm and thermodynamic models were employed to further investigate the adsorption process. The isotherm results indicated that the adsorption of CO2 by adsorbents occurred heterogeneously in patch-wise sites. Meanwhile, the thermodynamic parameters showed that the process was exothermic and spontaneous, with ΔH° falling below 20 (kJ/mol), showing physisorption phenomena.
期刊介绍:
The Journal of CO2 Utilization offers a single, multi-disciplinary, scholarly platform for the exchange of novel research in the field of CO2 re-use for scientists and engineers in chemicals, fuels and materials.
The emphasis is on the dissemination of leading-edge research from basic science to the development of new processes, technologies and applications.
The Journal of CO2 Utilization publishes original peer-reviewed research papers, reviews, and short communications, including experimental and theoretical work, and analytical models and simulations.