Pb2+ Adsorption Using Mixture of Kaolinite-Sago Waste and Bentonite-Sago Waste.

Abstract

Various efforts have been conducted to overcome heavy metal contamination, among other things with physical and chemical method such as chemical precipitation and ultra-filtration. However, these methods are costly and ineffective. Therefore, there is a need to find alternatives to investigate a low cost and effective method. In this experiment, heavy metal ions Pb2+ were adsorbed on sago waste, mixture of sago waste with kaolinite, and mixture of sago waste with bentonite. The adsorbents were activated using acid and base. The activated charcoal was used as a comparation. The result showed that all adsorbents made of mixture of sago waste with kaolinite and with bentonite were potential to adsorb Pb2+. However, sago waste with acid-activation and the mixture of sago waste acid-treated as well as the acid-treated kaolinite (75:25) adsorbents gave adsorption capacity higher than the others. Adsorption capacity of both adsorbents were higher than the activated charcoal. Adsorption type of the adsorbent can be evaluated by the determination of Langmuir and Freundlich isotherm test. The result showed that both adsorbents had Langmuir isotherm type, so it can be estimated that the adsorbed layers on the adsorbent surface is monolayer.

Berbagai upaya telah dilakukan untuk mengatasi pencemaran logam berat, di antaranya dengan metode fisikokimia seperti presipitasi kimia dan ultrafiltrasi, akan tetapi metode-metode tersebut mahal dan tidak efektif. Metode alternatif yang lebih murah dan efektif diperlukan untuk mengatasi pencemaran logam berat. Pada penelitian ini, adsorpsi ion logam berat Pb2+ dilakukan menggunakan ampas sagu, campuran ampas sagu dengan kaolin, dan campuran ampas sagu dengan bentonit. Adsorben yang dibuat terlebih dahulu diaktivasi secara asam dan basa. Arang aktif komersial digunakan sebagai pembanding. Hasil penelitian menunjukkan bahwa semua adsorben campuran ampas sagu dengan kaolin dan bentonit berpotensi untuk mengadsorpsi ion logam berat Pb2+. Namun adsorben ampas sagu teraktivasi asam dan campuran ampas sagu teraktivasi asam-kaolin (75:25) memiliki kapasitas adsorpsi yang paling tinggi. Kapasitas adsorpsi kedua adsorben ini lebih tinggi daripada arang aktif. Jenis isoterm adsorpsi dari kedua adsorben ini menunjukkan model isoterm Langmuir, artinya lapisan adsorbat yang terbentuk pada permukaan adsorben membentuk satu lapisan (monolayer).