CITRIC ACID MODIFIED ACTIVATED CARBON DERIVED FROM TEAKWOOD (Tectona grandis) SAWDUST AS AN ADSORBENT FOR COPPER IONS

SITI ALYANI DHANIRA, Prof. Dr. Bambang Rusdiarso, DEA; Dr. Eko Sri Kunarti, M.Si

2018 | Skripsi | S1 KIMIA

Modifikasi karbon aktif berbahan dasar serbuk kayu jati dengan asam sitrat telah dilakukan. Penelitian ini bertujuan untuk meningkatkan jumlah situs adsorpsi di permukaan adsorben dengan melakukan aktivasi karbon secara kimiawi oleh NaOH dan memodifikasi karbon aktif dengan asam sitrat. Karbon aktif termodifikasi asam sitrat dikarakterisasi menggunakan FT-IR, titrasi Boehm dan SEM. Analisis karbon aktif termodifikasi asam sitrat telah dilaksanakan untuk mengkaji parameter yang mempengaruhi daya adsorpsi ion tembaga (pH, waktu kontak, konsentrasi awal logam). Modifikasi karbon aktif dengan asam sitrat mampu meningkatkan jumlah gugus karboksilat pada permukaan adsorben dari 0,5176 mmol g-1 hingga 0,6769 mmol g-1. pH optimum adsorpsi ion tembaga oleh adsorben diperoleh pada pH 5. Isotherm adsorpsi mengikuti isotherm Freundlich dengan kapasitas adsorpsi sebesar 2,446 × 10-3 mol g-1. Reaksi adsorpsi mengikuti model kinetika Pseudo-orde kedua Ho dengan konstanta laju sebesar 23,79 g mmol-1 min-1.

Modification of activated carbon derived from teakwood sawdust with citric acid has been conducted. The purpose of the research was to increase the amount of adsorption site on the surface of the adsorbent by chemical activation of the carbon with NaOH and modification of the activated carbon with citric acid. The citric acid modified adsorbent was characterized with FT-IR, Boehm titration and SEM. Citric acid modified activated carbon had been analyzed to study the variables (pH, contact time, initial concentration) that affect the adsorption of copper ions. The modification of sawdust derived activated carbon with citric acid increased the carboxylic acid groups on the surface of the adsorbent, from 0.5176 mmol g-1 to 0.6769 mmol g-1. The optimum pH suitable for the adsorption was pH 5. The adsorption isotherm followed the Freundlich isotherm model and the adsorption capacity of the adsorbent was 2.446 × 10-3 mol g-1. The adsorption followed the Ho Pseudo-second order kinetical model with a rate constant of 23.79 g mmol-1 min-1.

Kata Kunci : teakwood sawdust, activated carbon, citric acid, copper, adsorption.