@phdthesis{digilib13272, month = {June}, title = { OPTIMALISASI PARAMETER pH PADA SINTESIS NANOSILIKA DARI PASIR BESI MERAPI DENGAN EKSTRAKSI MAGNET PERMANEN MENGGUNAKAN METODE KOPRESIPITASI }, school = {UIN SUNAN KALIJAGA}, author = {NIM. 10620008 DWI NOOR JAYANTI }, year = {2014}, note = {Pembimbing : Retno Rahmawati, M.Si }, keywords = {Key Words : coprecipitation method, extraction of magnet permanen, nanosilica, sand of Merapi. }, url = {https://digilib.uin-suka.ac.id/id/eprint/13272/}, abstract = {The optimization of pH parameter on nanosilica syhnthesis from sand of Merapi with magnet permanent extraction by using coprecipitation metods has been done. In this research, the syhnthesis was carried out by mixing and stirring 4 g of sand and NaOH 7M for 1 hour ({\texttt{\char126}}70-80oC) to get sodium silicate solution (Na2SiO3). The solution was filter and then HCl 2M solution is added in order to titration up to the last pH of solution (pH 7, pH 4, and pH 1). The result of syhnthesis is dried at {\texttt{\char126}}85oC for 3 hour till gotten SiO2 powder. Characterization of silica was carried out by using XRD (X-Ray Diffractions) to determine the phase formation and the size of the crystal formed, FTIR (Fourier Transformer Infrared Spectroscopy) for functional groups, and SEM (Scanning Electron Microscopy) to determine the morphology of the sample. Based on the analysis of XRD indicate that third sample have phase are 56,27\% (pH 7), 31,66\% (pH 4), dan 38,34\% (pH 1) with formed was near amorphous form. The decrease of the last pH of solution caused decrease of mass nanosilica from 4 g, is 0,3082 g (pH 7), 0,3022 g (pH 4), and 0,3000 (pH 1), and also increase of size particle is 89,55 {$\pm$} 5,23 nm (pH 7), 63,55 {$\pm$} 30,68 nm (pH 4), and 132,26 {$\pm$} 19,26 nm (pH 1). In general FTIR showed that third sample are similar pattern with the comparator silica Keiselgel 60 indicate of silanol (Si-OH) groups dan siloxane groups (Si-O-Si). Based on the result of morphology SEM of visible small particles form big particles (aglomerasi). } }