PENGARUH PERSEN BERAT BASALT, TEMPERATUR DANKECEPATAN PENGADUKAN TERHADAP PROSES PELINDIANBATUAN BASALT

Bubuk basalt yang digunakan telah lolos mesh 200 dengan ukuran 74 μm. Bubuk basalt dilakukan pelindian menggunakan asam oksalat dari belimbing wuluh. Variasi persen berat basalt yang digunakan dalam pelindian yaitu 10, 15 dan 20%. Variasi temperatur yang digunakan 30, 60 dan 90 oC. Variasi kecepatan pengadukan yang digunakan 200, 400 dan 600 rpm. Hasil pengujian XRF menunjukkan sebelum dan sesudah pelindian didominasi senyawa oksida SiO2, Al2O3, Fe2O3 dan CaO. Hasil XRD menunjukkan struktur fasa sebelum pelindian didominasi fasa-fasa mayor seperti fasa anorthite dan fasa iron silicate, setelah pelindian didominasi fasa mayor albite, anhydrite dan anorthite. Hasil pengujian AAS menunjukkan asam oksalat dari belimbing wuluh dapat melarutkan unsur besi yang maksimum pada persen berat 20%, temperatur 60 oC dan kecepatan pengadukan 400 rpm. Sebelum pelindian kandungan besi oksida sebesar 15,95%, setelah pelindian kandungan besi oksida menurun pada persen berat 10% sebesar 10,47%, temperatur 60 oC sebesar 6,31%, dan kecepatan pengadukan 200 rpm sebesar 6,31%. Kata kunci: basalt, pelindian, asam oksalat, belimbing wuluh, struktur fasa, besi oksida ii ABSTRACT Basalt powder used in the investigation was mesh of 200 with a size of 74 μm. Basalt powder was leached using oxalic acid from wuluh starfruit. Variations in weight percent basalt used in leaching are 10, 15 and 20%. Temperature variations used are 30, 60 and 90 oC. The variation of stirring speed used is 200, 400 and 600 rpm reorectively. The XRF test results showed that before and after leaching, the dominant oxide are SiO2, Al2O3, Fe2O3 and CaO. The XRD results showed that the phase structure before leaching was dominated by major phases such as the anorthite and iron silicate phases, after leaching dominated by albite, anhydrite and anorthite major phases. The AAS test results showed oxalic acid from wuluh starfruit can dissolve the maximum iron element at 20% weight percent, temperature 60 oC and stirring speed 400 rpm. Before leaching iron oxide content of 15.95%, after leaching iron oxide content decreased at 10% by weight of 10.47%, temperature of 60 oC by 6.31%, and stirring speed of 200 rpm at 6.31%. Keywords: basalt, leaching, oxalic acid, starfruit, phase structure, iron oxide