Uji Efektivitas dan Karakterisasi Komposit Tanah Andisol/Arang Tempurung Kelapa Untuk Adsorpsi Logam Berat Besi (Fe)
Authors: Pranoto Pranoto , Martini Tri , Maharditya Winda 
Published: June 2020

<p>Penelitian ini untuk mengetahui kapasitas adsorpsi komposit tanah andisol/arang tempurung kelapa sebagai adsorben logam berat besi (Fe) berdasarkan pada kondisi komposisi, pH dan waktu kontak yang optimum. Tanah andisol diaktivasi dengan larutan NaOH 3 M dan arang tempurung kelapa diaktivasi menggunakan larutan HCl 4 M. Komposit tanah andisol/arang tempurung kelapa dibuat dengan mencampurkan tanah andisol dan arang tempurung kelapa pada variasi komposisi 100:0, 75:25, 50:50, 25:75 dan 0:100 (b/b) Uji adsorpsi terhadap logam besi (Fe) dilakukan pada variasi pH larutan 1, 2, 3, 4, 5 dan 6 serta waktu kontak 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, dan 60 menit dengan sistem <em>batch</em>. Pengukuran konsentrasi akhir pada saat kesetimbangan dilakukan dengan menggunakan <em>Atomic Absorption Spectroscopy</em> (AAS).  Hasil karakterisasi adanya proses aktivasi dan pengompositan ditunjukkan pada spektra <em>Fourier Transform Infra Red</em> (FTIR) yang mengalami pergeseran bilangan gelombang. Karakterisasi pola difraksi <em>X-Ray Diffraction</em> (XRD) yang menunjukkan adanya puncak baru. Hasil analisis <em>Scanning Electron Microscope </em>(SEM) komposit menunjukkan bahwa permukaan adsorben telah ditutupi logam besi (Fe). Pembentukan komposit juga menunjukkan adanya peningkatan luas permukaan dan nilai keasaman komposit. Berdasarkan penelitian ini diperoleh bahwa proses adsorpsi terjadi pada kondisi optimum komposisi komposit tanah andisol/arang tempurung kelapa 75:25 (b/b), pH larutan besi (Fe) 5 dan waktu kontak selama 30 menit dengan kapasitas adsorpsi sebesar 0,54 mg/g dan presentase adsorpsi 91,57%. Isoterm adsorpsi mengikuti isoterm Freundlich dengan nilai R<sup>2</sup> sebesar 0,9456.</p><p><strong>Effectiveness Test and Characterization of Andisol Soil/Coconut Shell Charcoal for Adsorption of Iron (Fe).</strong> This research aims to determine the adsorption capacity composite of andisol soil and coconut shell charcoal as the adsorbent of iron (Fe) metal based on the composition condition, pH, and optimum contact time. Andisol soil was activated with NaOH 3 M solution, and coconut shell charcoal was activated with HCl 4 M solution. The composites were made under various composition of andisol soil/coconut shell charcoal of 100:0, 75:25, 50:50, 25:75 and 0:100 (w/w). The adsorption test was done on the pH variation of 1, 2, 3, 4, 5, 6 and used the contact time variation of 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 and 60 minutes in a batch method. The concentration analysis of iron (Fe) metal was done by atomic absorption spectroscopy (AAS). The characterization result of the activation process can be shown on the Fourier transform infrared (FTIR) spectra with the shifting peak. Characterization of X-ray diffraction (XRD) diffractogram showed the emergence of a new peak in andisol soil and coconut shell charcoal. The result of scanning electron microscope (SEM) characterization analysis showed that the surface of the adsorbent was covered in iron. The composite formation also showed an increase in surface area and composite acidity value. Based on the result of the research, it can be concluded that the adsorption process happens in the optimum condition in andisol soil/coconut shell charcoal composition of 75:25 (w/w), pH solution iron (Fe) metal of 5 and contact time of 30 minutes. The adsorption capacity was 0.54 mg/g and 91.57% for adsorption percentage. The isotherm adsorption followed Freundlich isotherm with R<sup>2</sup> values 0.9456.</p>