Acid etching behavior and mechanism in acid solution of iron components in basalt fibers

Abstract The acid-etching behavior and mechanism of basalt fiber in an acid solution determine the modification and application of basalt fiber. The effects of acid etching time, sulfuric acid concentration, acid etching temperature, and liquid–solid ratio on the acid etching process of basalt fiber were studied using a single-factor experiment. The chemical composition, phase, structure, and morphology of basalt fiber before and after acid etching were analyzed by XRF, XRD, SEM-EDS, and spectrophotometry. The dissolution mechanism of the iron component was speculated. The results showed that the dissolution of iron components could be promoted by increasing the acid etching time, sulfuric acid concentration, acid etching temperature, and liquid–solid ratio. When the sulfuric acid concentration was 1 mol L −1 , the acid etching temperature was 90°C, the liquid–solid ratio was 20 mL g −1 , and the reaction time was 4 h, the dissolution rate of iron components could reach 1.66%. During the acid etching process, the phase change of the basalt fiber was not obvious. Due to the dissolution of the iron component, the surface of the fiber could be chapped, resulting in the phenomenon of ravines and delamination, reducing the lattice distortion rate of the material.