Removal of hazardous crystal violet dye by low-cost P-type zeolite/carbon composite obtained from in situ conversion of coal gasification fine slag

Abstract

As the bulk of solid waste from coal chemical industry, coal gasification fine slag (CGFS) mainly consists of aluminosilicates and residual carbon. Currently, the common transformation strategy for CGFS entails the preparation of porous materials. However, this method utilizes only a part of the effective components in the slag. Specifically, either the silicon is used to synthesize zeolites, or the porous carbon is obtained through intensified separation. Therefore, it is highly desirable to achieve the simultaneous utilization of silicon and carbon resources in CGFS. In this work, CGFS was used as a low-cost raw material to prepare the P-zeolite/carbon composite in situ. The composite was characterized via XRD, 27 Al and 29 Si NMR, SEM, FT-IR, and Raman technique. Furthermore, the adsorption removal of crystal violet onto the composite was studied. The adsorption capacity was as high as 625.00 mg g −1 , which was much larger than the CGFS and most reported adsorbents. • The P-type zeolite/carbon composite was prepared in situ from CGFS. • The composite had flower-shape P-type zeolite and porous lamellar carbon. • The composite had large specific surface area and abundant functional groups. • The adsorption amount of crystal violet onto the composite was up to 625 mg g −1 .