ALTERING FERROUS SULPHATE TO SYNTHETIC GOETHITE

Catalyst is required in any reaction. Coal liquefaction is one of the processes to have need of it. The most common catalyst used in the process is ferrous based catalyst. It is very influenced by pyrhotite, which may be occurred from goethite while goethite can be composed of any iron sources. The research had the use of ferrous sulphate as the main iron source, which was reacted with caustic soda. Parameters on molar ratio of the FeSO4.7H2O/NaOH were 0.2 and 0.33, reaction time applied were 3.5; 6.5 and 17.15 hours, oxygen flow rates of 100; 200; 300; 400 and 500 cc/minute were also observed. The best result was achieved at 0.2 molar ratio of the FeSO4.7H2O/NaOH within 6.5 hours by oxidation process that was containing pure goethite, while 100 cc/minute of oxygen rate was enough for the process to be happened

PEMBUATAN ZIRKONIA SEMI STABIL DARI PASIR ZIRKON KALIMANTAN TENGAH DENGAN MENGGUNAKAN BAHAN PENSTABIL CAMPURAN CaO DAN MgO

Pembuatan zirkonia semi stabil (PSZ) dari pasir zirkon Kalimantan Tengah telah dilakukan dengan metode disosiasi termal pada skala laboratorium. Pasir zirkon Kalimantan Tengah yang digunakan mempunyai kadar 58,95% ZrO2 dengan pengotor terbanyak SiO2 28,21%, Fe2O3 1,30%, dan TiO2 6,68%. Kadar zirkon sebesar ini belum ekonomis apabila digunakan untuk pembuatan zirkonia semi stabil, oleh karena itu perlu dilakukan peningkatan kadar sehingga mencapai kadar >65% ZrO2. Peningkatan kadar pasir zirkon dilakukan melalui pemisahan mineral pengotornya dengan menggunakan kombinasi serangkaian peralatan yang terdiri dari meja goyang, pemisah magnetik, dan high tension separator (HTS). Dari hasil percobaan peningkatan kadar diperoleh konsentrat pasir zirkon berkadar 66,15% ZrO2, dengan perolehan sebesar 88,95%. Untuk memperoleh zirkonia semi stabil, bahan penstabil berupa campuran CaO dengan MgO ditambahkan ke dalam zirkonia berkadar 93,81% yang dibuat dari pasir zirkon dengan cara mixing dan sintering. Untuk mendapatkan kondisi pembuatan zirkonia semi stabil (PSZ) yang baik, perlu dilakukan percobaan dengan memvariasikan suhu sintering dan jumlah bahan penstabil. Kemudian produk yang diproleh dianalisis kadar ZrO2nya dan diuji bentuk struktur kristalnya dengan difraksi sinar-x. Hasil difraksi sinar-x terhadap zirkonia semi stabil (PSZ) yang diperoleh menunjukkan hanya puncak ZrO2 dengan bentuk struktur kristal tetragonal terjadi pada suhu sintering 1100oC dengan jumlah bahan penstabil 11% mol (5%berat) CaO dan 11% mol (3,6%berat) MgO

Phase formation during reduction of iron sand with soda ash flux addition

Iron sand deposit in Indonesia generally consisted of titanomagnetite with ilmenite lamelaa occurred in magnetite particle structure, therefore direct physical separation through magnetic method at particle size of 400 mesh only capable increasing total iron content up to 60%. In order to increase the grade of iron, decreasing TiO2 content in iron sand was applied by chemical method of alkaline fusion followed by grinding to 100 mesh and magnetic separation. Pre-oxidation was conducted prior to reduction and alkaline flux was added to coal based reduction system of in a rotary kiln. The alkali addition into the reduction system resulted to the formation of metallic iron and non metallic phases, in which sodium titanate compounds as nonmagnetic product can be separated from calcine using separator magnetic. XRD analyses of the concentrate and tailing as magnetic separation products showed concentrate was dominated by metallic phase compared to oxide phase and it doesn’t consisted iron-titan oxide and iron oxide. On the other hand, tailing was consisted iron-titan oxide and iron oxide