Sintesis Nanopartikel CoFe2O4-SiO2 Termodifikasi Sistein Sebagai Adsorben Ion [AuCl4]-

ANDRINI SETIARINI, Prof. Drs. Roto, M.Eng, Ph.D. ; Dr.rer.nat. Adhitasari Suratman, S.Si., M.Si.

2023 | Skripsi | S1 KIMIA

Sintesis nanopartikel CoFe2O4-SiO2 termodifikasi sistein sebagai adsorben ion [AuCl4]-telah dilakukan. Tujuan dari penelitian ini adalah untuk melakukan sintesis adsorben nanopartikel CoFe2O4-SiO2-Sistein, mengetahui kondisi optimum adsorpsi ion [AuCl4]-, serta mengetahui model isoterm dan kinetika adsorpsi ion [AuCl4]-. Sintesis nanopartikel CoFe2O4 dilakukan dengan metode kopresipitasi. Pelapisan dengan SiO2 menggunakan metode sol-gel, kemudian penambahan gugus -NH2 dengan (3-aminopropyl) trimethoxysilane (APTMS). Material hasil sintesis selanjutnya dimodifikasi dengan sistein. Material CoFe2O4-SiO2-Sistein hasil sintesis dikarakterisasi menggunakan spektrometer fourier transfor infrared(FTIR), x-ray diffraction (XRD), vibrating sample magnetometer (VSM) dan transmission electron microscope (TEM). Kajian adsorpsi ion [AuCl4]- meliputi variasi pH larutan, massa adsorben, konsentrasi awal larutan [AuCl4]-, dan waktu kontak. Nanopartikel magnetik CoFe2O4-SiO2-Sistein hasil sintesis memiliki diameter rata-rata sebesar 22 nm. Adsorpsi ion [AuCl4]- oleh adsorben nanopartikel CoFe2O4-SiO2-Sistein optimum pada pH 4, massa adsorben 8 mg, konsentrasi awal adsorbat 50 mg L-1 dan waktu kontak 720 menit. Proses adsorpsi ion [AuCl4]- oleh adsorben nanopartikel CoFe2O4-SiO2-Sistein mengikuti model isoterm adsorpsi Langmuir dengan energi sebesar 24,50 kJ mol-1dan mengikuti model kinetika adsorpsi orde dua semu dengan konstanta laju reaksi 1,2 x 10-4 g mg-1 menit-1 serta kapasitas adsorpsi optimum sebesar 102,04 mg g-1.

Synthesis of CoFe2O4-SiO2 nanoparticles modified with cysteine as [AuCl4]- adsorbent has been conducted. This research aimed to synthesize nanoparticle adsorbent CoFe2O4-SiO2-Cysteine, determine the optimum conditions of [AuCl4]- ion adsorption using nanoparticle CoFe2O4-SiO2-Cysteine adsorbent, and determine the kinetics and isotherm adsorption of [AuCl4]-. The coprecipitation method used in the synthesis of CoFe2O4, followed by coating with SiO2 using sol-gel method and was addition of -NH2 functional group using APTMS. Materials obtained from synthesis were modified with cysteine. The CoFe2O4-SiO2-Cysteine materials were characterized using fourier transfor infrared (FTIR) spectrometer, x-ray diffraction (XRD), vibrating sample magnetometer (VSM) and transmission electron microscope (TEM) instrument. The adsorption of [AuCl4]- ion was carried out by varying the pH solution, adsorbent dose, initial concentration of adsorbate, and contact time. CoFe2O4-SiO2-Cysteine nanoparticles were successfully synthesized with average diameter 22 nm. The adsorption of [AuCl4]- ion with CoFe2O4-SiO2-Cystein adsorbent was optimum at pH 4, 8 mg adsorbent mass, 50 mg L-1initial concentration of adsorbate, and 720 min of contact time. The adsorption followedthe Langmuir isotherm model with energy 24.50 kJ mol-1 and followed the pseudosecond-order kinetic model with the adsorption rate constant of 1.2 x 10-4g mg-1min-1 and optimum capacity of 102.04 mg g-1.

Kata Kunci : adsorpsi, CoFe2O4, ion [AuCl4]- , sistein.