PENGARUH VARIASI HCl PADA PEMURNIAN SILIKA BERBASIS BATU APUNG

Abstract

Silica from pumice natural rock was extracted by varying HCl of 1M and 2M. Fristly, pumice was heated to 400°C for 4 hours to activate the component of material.Three steps were used in obtaining pure silica. Silica extraction by using NaOH, silica titration by using H 2 SO 4 , and purification silica with HCl. The purified powder was calcined at 800°C. The characterization of XRD (X-Ray Diffraction) and SEM-EDS (Scanning Elektron Microscopy - Energy Dispersive Spectrometry) were performed for samples after and before purification to know the phase structure and microstructure and pumice powder content. The XRD results was show diffraction pattern of the amorphous shaped SiO 2 with some crystalline peaks is an other oxide compound than SiO 2 for the starting material, and an anorite crystal phase in the HCl 1M and 2M variations. This is confirmed by EDS results what showing the silica content has the highest percentage of 65.88% for the raw material, 67.83% for HCL 1M and 69.63% for HCl 2M variation after purification. While the SEM results identified the microstructure for the raw material has a clear but not entirely homogeneous that is the identification of the sample in an amorphous state, whereas the sample after purification of the microstructural result shows non-homogeneous grain size, unclear grain boundary boundaries and an algomeration (agglomeration ) which is also the identification of the sample in an amorphous state. Silica from pumice natural rock was extracted by varying HCl of 1M and 2M. Fristly, pumice was heated to 400°C for 4 hours to activate the component of material.Three steps were used in obtaining pure silica. Silica extraction by using NaOH, silica titration by using H 2 SO 4 , and purification silica with HCl. The purified powder was calcined at 800°C. The characterization of XRD (X-Ray Diffraction) and SEM-EDS (Scanning Elektron Microscopy - Energy Dispersive Spectrometry) were performed for samples after and before purification to know the phase structure and microstructure and pumice powder content. The XRD results was show diffraction pattern of the amorphous shaped SiO 2 with some crystalline peaks is an other oxide compound than SiO 2 for the starting material, and an anorite crystal phase in the HCl 1M and 2M variations. This is confirmed by EDS results what showing the silica content has the highest percentage of 65.88% for the raw material, 67.83% for HCL 1M and 69.63% for HCl 2M variation after purification. While the SEM results identified the microstructure for the raw material has a clear but not entirely homogeneous that is the identification of the sample in an amorphous state, whereas the sample after purification of the microstructural result shows non-homogeneous grain size, unclear grain boundary boundaries and an algomeration (agglomeration ) which is also the identification of the sample in an amorphous state.