Obtención de sol de sílice (H2SiO3), utilizando silicato de sodio (Na2SiO3) con ácido sulfúrico (H2SO4), para la industria de la curtiembre

Abstract

The objective of this study was to synthesize silica sol from the acidification of sulfuric acid plus sodium silicate. To achieve this, three sodium silicate solutions were prepared at different concentrations, these were mixed with a 17% dilute sulfuric acid solution, until a whitish colloidal suspension was obtained. The pH of the final solutions obtained was determined. Subsequently, tests were carried out at different temperatures to find the influence of this on the process, the colloidal suspensions obtained, as well as the gel formed were analysed in an infrared spectrophotometer to compare the functional groups that they present versus the functional groups that a conventional chromium salt present. Finally, tanning tests were carried out with the silica sol obtained plus an aldehyde where the typical quality parameters of leather were analysed, which are abrasion to dry rubbing, percentage of elongation, shrinkage at temperature and tensile strength, these results were compared with the data of leather tanned with chromium salts. Statistical tests such as multiple ranges, anova, and determination of means were carried out for comparison. The result is that the process must be carried out at room temperature reaching a pH of 2.5, the infrared spectrum reveals that the functional groups of sodium silicate are like the chromium salts used for the tanning process. Statistical analysis shows that the silica sol obtained from a solution of 1/5 of sodium silicate presents statistically similar quality parameters to those obtained from a conventional chromium salt tanning.