Effect of Activation on Gelatin Modified ZnO Using Tamarind, Lime, and Wuluh Starfruit as Adsorbents Methylene Blue Maria Ulfa (a*), Ika Uswatun Hasanah (a), Sandini Ajeng Istanti (a), and Hafid Al Afif (a)
(a) Study Program of Chemistry Education, Faculty of Teacher Training and Education, Sebelas Maret University, Jl. Ir. Sutami 36A, 57126 Surakarta, Central Java Indonesia
*ulfa.maria2015[at]gmail.com
Abstract
The synthesis of environmentally friendly natural acid activated ZnOG has been successfully carried out using the hydrothermal method as an innovation to replace synthetic acid. Hydrothermal method with a temperature of 100oC for 24 hours and activated using extracts of lime, tamarind, and star fruit wuluh then in the oven at 100 celcius for 24 hours and continued with calcination. The adsorbent formed was then characterized using FTIR (Fourier Transform Infrared Spectroscopy) and XRD (X-Ray Diffraction). FTIR results on ZnOG activated with 3 natural acids showed an absorption pattern at 571 cm-1 and 1689 cm-1 which indicated the presence of the Zn-O and Zn-RCOO- functional group. The degree of crystallinity of activated ZnOG extracts of tamarind and starfruit were 60.39% and 72.65%, respectively, with a crystal size of 6.34 nm- and 8.06 nm. The adsorption process of methylene blue using ZnOG adsorbent as much as 50 mg in 120 minutes with a speed of 150 rpm. From the research results, it is known that the activator of lime extract has the highest adsorption capacity compared to tamarind and wuluh starfruit extract, which is 62.881 mg/g.
