ADSORPTION of METHYL ORANGE DYE USING POWDERED ACACIA (Crassicarpa) BARK AS AN ADSORBENT - Mukhlis; Nafiah Pratiwi; Indriyana Syafitri Aswir; Itnawita; Sofia Anita; T. Abu Hanifah (Analit : Analytical and Environmental Chemistry, 2025)
ABSTRAK Serbuk kulit kayu Acacia crassicarpa adalah biomassa lignoselulosa yang kaya akan selulosa, diteliti sebagai biosorben untuk menghilangkan Metil Oranye (MO) dari larutan berair. Studi ini bertujuan untuk menentukan kondisi adsorpsi optimum, termasuk dosis adsorben, pH, waktu kontak, kecepatan pengadukan, konsentrasi adsorbat, dan suhu. Eksperimen adsorpsi dilakukan menggunakan sistem batch, dan adsorben dikarakterisasi menggunakan analisis FTIR, SEM-EDS, dan BET. Kondisi optimum diperoleh pada dosis 0,75 g, pH 2, waktu kontak 80 menit, kecepatan pengadukan 200 rpm, konsentrasi MO 20 ppm, dan suhu 30 °C, mencapai efisiensi adsorpsi sebesar 82,34% dan kapasitas sebesar 5,6492 mg/g. SEM-EDS menunjukkan morfologi berpori yang didominasi oleh unsur karbon dan oksigen. Analisis BET menunjukkan luas permukaan sebesar 0,460 m²/g, sedangkan FTIR mengkonfirmasi keberadaan gugus fungsional hidroksil, karbonil, dan aromatik yang terlibat dalam adsorpsi. Hasil ini membuktikan bahwa akasia dapat menjadi adsorben.     ABSTRACT Acacia crassicarpa bark powder, a lignocellulosic biomass rich in cellulose, was investigated as a biosorbent for the removal of Methyl Orange (MO) from aqueous solutions. This study aimed to determine the optimum adsorption conditions, including adsorbent dosage, pH, contact time, stirring speed, adsorbate concentration, and temperature. Adsorption experiments were conducted using a batch system, and the adsorbent was characterized using FTIR, SEM-EDS, and BET analyses. The optimum conditions were obtained at a dosage of 0.75 g, pH 2, contact time of 80 min, stirring speed of 200 rpm, MO concentration of 20 ppm, and temperature of 30 °C, achieving an adsorption efficiency of 82.34% and a capacity of 5.6492 mg/g. SEM-EDS showed a porous morphology dominated by carbon and oxygen elements. BET analysis showed a surface area of ​​0.460 m²/g, while FTIR confirmed the presence of hydroxyl, carbonyl, and aromatic functional groups involved in the adsorption. These results prove that acacia can be an adsorbent.