Adsorpsi asam lemak bebas dan zat warna menggunakan campuran kaolin-limbah padat tapioka

Abstract

Adsorption of free fatty acids in used cooking oil and methylene blue dye is studied. The results showed that the mixture of kaolin and tapioca solid waste is a potential adsorbent for the adsorption free fatty acids and dyes. The effect of kaolin activation treatment, such as heating temperature and the use of acid is also studied. The best activation results for the kaolin activation used in the free fatty acid adsorption was heating treatment at 750 °C followed by treatment with H2SO4 30%, whereas for methylene blue adsorption by acid treatment only. Activation of tapioca solid waste was using 30% H3PO4 treatment. Optimum conditions for adsorption, adsorption capacity, and adsorption efficiency of a mixture of kaolin and tapioca solid waste showed different results and specific for each type of sample used. For the same amount of adsorbent, free fatty acid adsorption was reached in 90 minutes using the ratio of activated kaolin and tapioca solid waste of 25:75 (1:3). Meanwhile, methylene blue adsorption was achieved at 30 minutes with the ratio of activated kaolin and tapioca solid waste of 75:25 (3:1). The results showed that the type of adsorption isotherm for free fatty acids was Freundlich isotherm, whereas for methylene blue adsorption was Langmuir isotherm.