Sintesis dan Karakterisasi Adsorben Ion Fe3+ dan Zn2+ dari Limbah Lumpur IPAL Industri Tekstil Menggunakan Aktivator KOH dan H3PO4

Abstract

Limbah lumpur IPAL industri tekstil berpotensi dikonversi menjadi adsorben bernilai guna. Penelitian ini bertujuan mensintesis dan mengarakterisasi adsorben berbasis lumpur IPAL tekstil menggunakan variasi agen pengaktif kimia H3PO4 (10% v/v, 30% v/v, 50% v/v) dan KOH (5,83%, 17,47%, dan 29,11%), serta mengevaluasi performa penyerapan dan selektivitasnya terhadap kation logam berat Fe3+ dan Zn2+. Karakterisasi fisikokimia diuji mengacu pada SNI 06-3730-1995, meliputi analisis proksimat, daya serap iodin dan metilen biru, serta analisis gugus fungsi menggunakan FTIR. Hasil pengujian menunjukkan seluruh sampel memenuhi standar SNI untuk kadar air (2.79% - 12.05%) dan kadar abu (5.7% - 9.1%). Nilai daya serap iodin belum mencapai standar minimum dengan capaian tertinggi 137.05 mg/g pada KOH 29,11%, namun uji metilen biru menunjukkan pembentukan mesopori fungsional hingga 199.76 mg/g pada H3PO4 30% v/v. Uji adsorpsi menunjukkan perlakuan KOH 29,11% menghasilkan kapasitas adsorpsi maksimum teoritis (qmax) paling stabil (0.578 mg/g untuk Fe3+ dan 0.551 mg/g untuk Zn2+).

Textile industrial Wastewater Treatment Plant (WWTP) sludge has the potential to be converted into valuable adsorbents. This study aims to synthesize and characterize WWTP sludge-based adsorbents using chemical activating agents of H3PO4 (10% v/v, 30% v/v, and 50% v/v) and KOH (5.83%, 17.47%, and 29.11%), and evaluate their removal performance and selectivity towards Fe3+ and Zn2+ heavy metal cations. Physicochemical characterization was tested referring to SNI 06-3730-1995, including proximate analysis, iodine and methylene blue adsorption, and FTIR functional group analysis. The results showed that all samples met the SNI standards for moisture content (2.79% - 12.05%) and ash content (5.7% - 9.1%). Although the iodine number did not reach the minimum standard with the highest value of 137.05 mg/g in KOH 29,11%, the methylene blue test confirmed functional mesopore formation up to 199.76 mg/g in H3PO4 30% v/v. Adsorption tests showed that KOH 29.11% treatment yielded the most stable theoretical maximum adsorption capacity (qmax) of 0.578 mg/g for Fe3+ and 0.551 mg/g for Zn2+.