Kajian adsorpsi Mg/Al Hidrotalsit terkalsinasi (Mg/Al HT-K) untuk adsorpsi zat warna Remazol Red RB telah dilakukan. Mg/Al HT-K disintesis menggunakan metode kopresipitasi dari Mg(NO3)2•6H2O dan Al(NO3)3•9H2O pada pH 10 dengan perbandingan mol Mg(II) dan Al(III) 2:1, dilanjutkan dengan pemanasan temperatur tinggi (450 ºC) selama 5 jam. Adsorben hasil sintesis dikarakterisasi menggunakan X-Ray Diffraction (XRD), Fourier Transform Infra Red Spectroscopy (FT-IR), dan Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX). Mg/Al HT-K digunakan untuk mengadsorp zat Remazol Red RB sehingga diperoleh kondisi optimum adsorpsi yang meliputi derajat keasaman (pH), waktu kontak, dan konsentrasi larutan zat warna.
Hasil penelitian menunjukkan kondisi optimum adsorpsi zat warna Remazol Red RB menggunakan Mg/Al HT-K optimum pada pH 3 dengan konsentrasi optimum sebesar 35 mg/g dan volume sebanyak 20 mL selama 150 menit. Adsorben Mg/Al HT-K memiliki kemampuan adsorpsi dengan kapasitas adsorpsi sebesar 24,529 mg/g. Kinetika adsorpsi zat warna Remazol Red RB pada Mg/Al HT-K mengikuti kinetika orde kedua semu, dengan konstanta laju adsorpsi atau k2 sebesar 5,40 x 10-2 g mg-1 min-1. Adsorpsi Remazol Red RB pada Mg/Al HT-K mengikuti model isoterm Freundlich dengan nilai KF sebesar 29,758 mol/L dan nilai n sebesar 1,022.
An adsorption study of calcined Mg/Al Hydrotalcyte (Mg/Al HT-K) for the adsorption of Remazol Red RB dye has been accomplished. Mg/Al HT-K was synthesized using the coprecipitation method of Mg(NO3)2•6H2O and Al(NO3)3•9H2O at pH 10 with a molar ratio of Mg(II) and Al(III) 2:1, followed by high heating temperature (450 ºC) for 5 hours. The synthesized adsorbents were characterized using X-Ray Diffraction (XRD), Fourier Transform Infra Red Spectroscopy (FT-IR), and Scanning Electron Microscopy-Energy Dispersive X- Ray (SEM-EDX). Calcined Mg/Al HT is used to adsorb Remazol Red RB so that optimal adsorption conditions are obtained which include acidity (pH), contact time, and concentration of dye solution.
The results showed that the optimal condition of adsorption of Remazol Red RB dye using Mg/Al HT-K was optimal at pH 3 with an optimum concentration of 35 mg/g and a volume of 20 mL for 150 minutes. The adsorption kinetics of Remazol Red RB dye in Mg/Al HT-K followed the pseudo second order kinetics, with an adsorption rate constant of 5.40 x 10-2 mg g-1 min-1. In Mg/Al HT-K followed the Freundlich isothermic model with a KF value of 29.758 mol/L and an n value of 1.022.
Kata Kunci : adsorpsi, isoterm, kalsinasi, Mg/Al Hidrotalsit, Remazol Red RB
