Electronic Theses and Dissertation

Imobilisasi fotokatalis α-Fe2O3-TiO2/Kitosan pada plat kaca telah dilakukan menggunakan sistem layer by layer. Formulasi komposit α-Fe2O3-TiO2 dibuat dengan perbandingan massa (g) α-Fe2O3 : TiO2 1 : 16 dan massa optimum kitosan 30 mg. Hematit dan komposit α-Fe2O3-TiO2 dikarakterisasi menggunakan XRD untuk mengetahui senyawa dan struktur kristal pada hematit dan komposit α-Fe2O3-TiO2. Morfologi permukaan fotokatalis α-Fe2O3-TiO2/Kitosan dikarakterisasi menggunakan SEM crossection. Aktivitas fotokatalitik fotokatalis α-Fe2O3-TiO2/Kitosan terimobilisasi dievaluasi pada penghilangan zat warna Naphthol Blue Black (NBB) dan Rhodamin B (RhB). Hasil penelitian menunjukkan bahwa aktivitas fotokatalis yang optimum dalam mendegradasi zat warna NBB yaitu pada massa 40 mg, pH 5 dan konsentrasi 15 mg/L, konstanta laju reaksi penghilangan zat warna NBB adalah 0,0497 menit-1 dan persentase penghilangan 98,81%. Nilai konstanta laju reaksi fotokatalis terhadap zat warna RhB sebesar 0,0346 menit-1 dan persentase penghilangan 94,69% pada kondisi optimum yaitu massa fotokatalis sebesar 60 mg, pH 6, dan konsentrasi 3 mg/L pada waktu radiasi selama 90 menit. Penggunaan kembali fotokatalis α-Fe2O3-TiO2/Kitosan pada penghilangan zat warna NBB dan RhB dilakukan sebanyak 5 kali pengulangan dan terjadi penurunan aktivitas fotokatalitik dari 98,81% hingga 93,25% untuk zat warna NBB dan 94,69% hingga 90,85% pada zat warna RhB.

The immobilization of α-Fe2O3-TiO2/Chitosan photocatalyst on glass plates has been carried out using a layer by layer system. The formulation of α-Fe2O3-TiO2 composite was prepared with a mass ratio (g) of α-Fe2O3 : TiO2 of 1 : 16 and an optimum chitosan mass of 30 mg. Hematite and α-Fe2O3-TiO2 composite were characterized using XRD to determine the compounds and crystal structures present in hematite and the composite. The surface morphology of α-Fe2O3-TiO2/Chitosan photocatalyst was characterized using SEM cross-section. The immobilized α-Fe2O3-TiO2/Chitosan photocatalyst's photocatalytic activity was evaluated for the removal of Naphthol Blue Black (NBB) and Rhodamine B (RhB) dyes. The research results indicate that the optimum photocatalytic activity for degrading NBB dye occurs at a mass of 40 mg, pH 5, and a concentration of 15 mg/L. The rate constant for the removal of NBB dye is 0.0497 min-1 with a removal percentage of 98.81%. The rate constant for the photocatalyst reaction towards RhB dye is 0.0346 min-1 with a removal percentage of 94.69% under optimum conditions, namely a photocatalyst mass of 60 mg, pH 6, and a concentration of 3 mg/L with a radiation time of 90 minutes. The reuse of α-Fe2O3-TiO2/Chitosan photocatalyst for the removal of NBB and RhB dyes was conducted for 5 repeated cycles, resulting in a decrease in photocatalytic activity from 98.81% to 93.25% for NBB dye and from 94.69% to 90.85% for RhB dye.