UJI KINERJA ADSORBEN TONGKOL JAGUNG TEROPTIMASI TERHADAP LARUTAN ION TIMBAL SECARA RESPONSE SURFACE METHODOLOGY

Abstract

Tongkol jagung memiliki kandungan lignoselulosa yang tinggi sehingga berpotensi dimanfaatkan sebagai bahan baku adsorben, namun kapasitas adsorpsi masih terbatas sehingga diperlukan proses aktivasi. Penelitian ini bertujuan mengaktivasi tongkol jagung serta menentukan kondisi optimum adsorpsi menggunakan Response Surface Methodology–Box Behnken Design. Tongkol jagung dikarbonisasi, kemudian diaktivasi secara fisika, kimia, dan hibrida. Karakterisasi adsorben meliputi kadar air, kadar abu, kadar bahan volatil, bilangan iodin, dan analisis gugus fungsi menggunakan Fourier Transform Infrared Spectroscopy. Aktivasi kimia menghasilkan kinerja terbaik dengan efisiensi adsorpsi tertinggi. Kondisi optimum adsorpsi diperoleh pada konsentrasi awal Pb²? 10 mg/L, waktu kontak 100 menit, dan massa adsorben 0,20 g dengan efisiensi adsorpsi 99,26%. Keandalan kondisi optimum didukung oleh hasil analysis of variance yang menunjukkan bahwa model kuadratik bersifat signifikan (p < 0,0002) dengan koefisien determinasi R² = 0,9894.

The lignocellulosic content of corn cobs supports their potential as a raw material for adsorbents, however their adsorption capacity remains limited, necessitating an activation process. This study aimed to activate corn cobs and determine the optimum adsorption conditions using Response Surface Methodology–Box Behnken Design. Corn cobs were carbonized and subsequently activated through physical, chemical, and hybrid methods. Characterization of the adsorbent included moisture content, ash content, volatile matter, iodine number, and functional group analysis using Fourier Transform Infrared Spectroscopy. Chemical activation resulted in the best performance, with the highest adsorption efficiency. The optimum adsorption conditions were obtained at an initial Pb²? concentration of 10 mg/L, a contact time of 100 minutes, and an adsorbent mass of 0,2 g, yielding an adsorption efficiency of 99,26%. The reliability of these optimum conditions was supported by analysis of variance, which showed that the quadratic model was significant (p < 0,0002) with a coefficient of determination of R² = 0,9894.