Synthesis of Large Pore Carbon Nanoparticles for Removal of Malachite Green

Abstract

In this work, we have synthesized high surface area and large pore volume carbon nanoparticles (CNP) by a simple and easy sol-gel approach. The sol was prepared by mixing Pluronic F127 and phloroglucinol-terephthalaldehyde in acidic ethanol solution and the gel was formed after the vacuum removal of ethanol. In the sol-gel process, hydrophobic segments of Pluronic F127 forms enhanced hydrogen bonding with trihydroxyl groups of phloroglucinol. A polymeric network of carbon precursor was also prepared by making the interconnectivity between four phloroglucinol and one terephthalaldehyde molecules. After thermal polymerization and carbonization of the gel, the CNP had a very high surface area (1441 m² g⁻¹) and large pore volume (1.7 cm³ g⁻¹) with narrow micropore (1.0 nm) and mesopore (2.3 nm) diameters. The mesopore was developed due to the enhanced hydrogen bonding between Pluronic F127 and phloroglucinol, while the micropores were generated due to hydrocarbon polymeric network of phloroglucinol-terephthalaldehyde. The CNP had a size about ca. 20 nm. The CNP were applied for the removal of the highly hazardous water pollutant malachite green (MG) and achieved a very high adsorption capacity (1892 mg g⁻¹). The commercials powder activated carbon (PAC) was also applied for the removal of MG and achieved an adsorption capacity of PAC was 1390 mg g⁻¹. It believes that shape and size of CNP and PAC played an important role in the adsorptive removal of MG.