Experimental study of CO2 capture enhanced by coal fly ash-synthesized NH2-MCM-41 coupled with high gravity technology

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2020-11, Vol.400, p.125946, Article 125946
• Main Authors: Cheng, Shang-Yuan, Liu, You-Zhi, Qi, Gui-Sheng
• Format: Article
• Language: English
• Subjects: CO2 capture; Coal fly ash; MCM-41; Nanofluids; Rotating packed bed
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2020.125946

•Synthesis of NH2-MCM-41 from solid waste coal fly ash to prepare nanofluids.•Nanofluids coupled with high gravity technology intensify CO2 absorption process.•The grazing effect and hydrodynamic effect were enhanced under high gravity field.•CO2 capture efficiency reached 95.7%. A new technology based on high gravity coupled nanofluids intensification mass transfer technology for efficiently capture CO2 was adopted in this work. It can overcome the mass transfer limitation of CO2 and enhance the capture effect. The nanoparticles MCM-41 was synthesized from coal fly ash and functionalized with (3-aminopropyl) triethoxysilane. The nanoparticles NH2-MCM-41 was dispersed in diethylenetriamine (DETA) by ultrasonic dispersion method. XRD, SEM, FTIR, N2 adsorption-desorption and TG were used to characterize the physicochemical properties of NH2-MCM-41 materials. Experimental results suggested that the existence of NH2-MCM-41 nanoparticles in DETA solution could effectively improve CO2 capture. The optimum conditions were the high gravity factor of 48.09, liquid-gas ratio of 0.07 and NH2-MCM-41 dosage of 0.1 wt%. Compared with the results of using DETA solution without adding NH2-MCM-41, CO2 capture efficiency was improved by 4.7% due to the enhancement of grazing effect and hydrodynamic effect in the high gravity environment. The combination of the two process intensification technologies reduces the mass transfer resistance, strengthens the mass transfer process of CO2 and enhances the CO2 capture effect. This work might offer a promising and green approach for production of MCM-41 to capture CO2 by combing high gravity technology. Turning coal fly ash into treasure, harm into profit, realizing waste control waste and green environmental protection.