EKSTRAKSI Au(III) DARI LIMBAH PRINTED CIRCUIT BOARD MENGGUNAKAN SISTEM DUA FASA LARUTAN BERAIR POLIETILEN GLIKOL/(NH4)2SO4

GATUT ARI WARDANI, Prof. Sri Juari Santosa, M.Eng.

2015 | Tesis | S2 Ilmu Kimia

Ekstraksi Au(III) dari limbah Printed Circuit Board (PCB) dengan sistem dua fasa larutan berair polietilen glikol/(NH4)2SO4 telah dilakukan. Penelitian dilakukan melalui tiga tahap. Tahap pertama adalah pelarutan selektif limbah PCB. Tahap kedua adalah pelarutan limbah PCB dengan akuaregia. Tahap terakhir adalah ekstraksi Au(III) dari larutan hasil pelarutan limbah PCB menggunakan sistem dua fasa larutan berair polietilen glikol/(NH4)2SO4. Proses pelarutan selektif tembaga dilakukan menggunakan campuran H2O2 30% (v/v) dan H2SO4 4 M dengan rasio volume 3 : 1 dan perendaman selama 3 hari. Pelarutan dilakukan menggunakan akuaregia dengan bantuan gelombang mikro selama 90 detik. Kandungan logam dari sampel limbah PCB ditentukan dengan analisis X-ray fluorescence (XRF). Kandungan tembaga dari larutan hasil pelarutan selektif ditentukan dengan AAS. Kandungan emas yang larut dalam akuaregia dan yang terekstrak dalam PEG dianalisis menggunakan spektrofotometer UV-Vis, sedangkan kandungan logam-logam lain yang larut dalam akuaregia dianalisis dengan Inductively Coupled Plasma Optical Emission Spectromerty (ICP-OES). Hasil penelitian menunjukkan bahwa pelarutan selektif limbah PCB menghasilkan konsentrasi tembaga 25.415 mg/kg. Pelarutan emas dari limbah PCB menggunakan akuaregia dengan dan tanpa pelarutan selektif menghasilkan konsentrasi Au(III) masing-masing sebesar 2.308 mg/kg dan 1.244 mg/kg. Emas(III) dapat diekstraksi (95,7%) dalam fasa PEG pada pH 2,0. Keberadaan ion Zn2+ dan Cu2+ dalam larutan dapat menurunkan efisiensi ekstraksi Au(III). Keberadaan ion klorida tambahan tidak berpengaruh secara signifikan terhadap efisiensi ekstraksi Au(III) dari larutan hasil pelarutan limbah PCB. Emas(III) berhasil diekstraksi dari limbah PCB sebesar 42%. Kata kunci: ekstraksi, emas, polietilen glikol, Printed Circuit Board

Extraction of gold(III) from printed circuit board (PCB) waste using two phase system of aqueous polyethylene glycol/(NH4)2SO4 was performed. The research was carried out through three steps. The first step was selective dissolution of PCB waste. The second step was dissolution of PCB waste in aqua regia. The final step was extraction of gold(III) from printed circuit board (PCB) waste using two phase system of aqueous polyethylene glycol/(NH4)2SO4. Selective dissolution processes of copper metals have been performed by using mixture of H2O2 30% (v/v) and H2SO4 4 M with the volume ratio 3 : 1 and immersion for 3 days. The dissolution of PCB waste was performed by using aqua regia microwave assisted for 90 seconds. Metal composition of PCB waste sample was determined by X-ray fluorescence spectrometry analysis (XRF). Total amount of copper in selective dissolution solution was determined by AAS. Total amount of gold which soluble in aqua regia and extracted in PEG phase were analyzed by UV-Vis spectrofotometer, whereas the non-target metals composition which soluble in aqua regia were analyzed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The result showed that selective solution of PCB waste yield 25,415 mg/kg of copper. The dissolution of gold from PCB waste using aqua regia, both with and without selective dissolution yield Au(III) 2,308 mg/kg and 1,244 mg/kg respectively. Gold(III) is quantitatively extracted (95.7%) into PEG-rich phase in pH = 2. Presence of Zn2+ and Cu2+ ions in solution could decrease efficiency extracted of Au(III). Presence of additional chloride did not influence significant toward extraction efficiency of the Au(III) from solution that dissolution of PCB waste. The Au(III) had extracted succesfully from PCB waste yield 42%. Keywords: extraction, gold, polyethylene glycol, Printed Circuit Board

Kata Kunci : ekstraksi, emas, polietilen glikol, Printed Circuit Board; extraction, gold, polyethylene glycol, Printed Circuit Board