MODIFIKASI KIMIA ABU DASAR BATUBARA UNTUK ADSORPSI METIL VIOLET; CHEMICAL MODIFICATION OF COAL BOTTOM ASH FOR THE ADSORPTION OF METHYL VIOLET

Hafid, Muhammad Samsudin, Nurul Hidayat Aprilita

2015 | Skripsi | FMIPA

Coal bottom ash chemical modification has been studied to adsorp methyl violet. This research was started by coal bottom ash and modified-bottom ash characterization using FTIR, XRD and BET analyzer. Adsorption variables in this research were adsorbent mass, contact times, adsorbate concentration, temperature, and pH. The result showed that the main components of coal bottom ash are SiO2 and Al2O3. Chemical modification of bottom ash using NaOH 5 M produced some zeolite phases such as zeolite Y and zeolite A that could increase the specific surface area, diameter pore average, and pore volume. The specific surface area of adsorbent was increased from 19.73 to 48.03 m2/g, pore diameter size from 40.90 to 120.00 Å, and pore volume from 2.02 ×10-2 to 1.44 ×10-1 cc/g. The optimum adsorption condition of 50 mg/L methyl violet was achieved using 0.8 g adsorbent. The optimum time of adsorption using AD 5 M and AD were 60 and 90 minutes, respectively. The optimum adsorption pH for both adsorbent was 11. Pseudo second order (Ho) was fit for methyl violet adsorption for both adsorbents and the initial sorption rate for AD and AD 5 M was 1.19 and 5.02 mg/g.min. AD and AD 5 M followed the Langmuir and Freundlich adsorption isotherm model, respectively, which their adsorption capacity was 5.65 and 16.31 mg/g, each. The enthalpy of adsorption for AD and AD 5 M was 31.23 and 14.3 kJ/mol.

Kata Kunci : Coal bottom ash; adsorption; zeolite.