Chrome-Free Tanning: Effect of a Combination Tannage Based on Mimosa and Biogenic Silica from Rice Husk

Chromium (III) sulfate is a popular tanning agent for producing leather. However, chrome wastewater one of the problems in leather industry. To prevent this, using vegetable materials can be used process. One natural ingredients that mimosa. mimosa relatively expensive, so substitute/combination needed to make costs cheaper. This research aims determine effect combination and silicic acid from rice husk (RHSA) tanners on quality tanned produced. uses completely randomized factorial design with RHSA as factors. The analysis shows best treatments were 20% RHSA. In addition, treatment met standard. resulting shrinkage temperature was 84 °C, tear strength 39.98 N mm-1, tensile 26.42 mm-2 elongation at break 41%. Combination also no significant difference conventional reduces without decreasing quality.