Pemodelan Matematis Reaksi Oksidasi Katalitik Fero Sulfat Menjadi Feri Sulfat

Abstract

Larutan fero sulfat (FeSO4) dibuat dengan melarutkan besi ke dalam asam sulfat. Fero sulfat dioksidasi memakai katalisator mangaan dioksid untuk membentuk feri sulfat. Reaksi merupakan reaksi heterogen tiga fasa sehingga kinetika reaksinya cukup komplek. Penelitian ini bertujuan mengembangkan model matematis pada kinetika reaksi tiga fase. Reaksi djalankan pada kondisi isotermal dan isobarik pada rekator yang berupa labu leher tiga. Percobaan dilakukan pada suhu 323K sampai 353K dan konsentrasi katalisator 1,7 g/L. Hasil penelitian menunjukan bahwa kinetika reaksi dapat didekati dengan model quasi steady state dan rekasi kimia pada permukaan katalisator merupakan langkah yang menentukan kinetika reaksi.

Kata kunci: pemodelan matematis, kinetika, langkah penentu

Iron was dissolved in a sulfuric acid to form a concentrated ferrous sulphate (FeSO4) solution. This research was conducted to form ferric sulfate by catalytic oxidation of ferrous sulfate using manganese dioxide as catalyst. The system was a three-phase heterogeneous reaction with a quite complex kinetics The present study aimed at developing a mathematical modeling of three-phase reaction kinetics that involved gas, liquid and solid. Oxidation was undertaken in an isothermal isobaric condition in a three-neck flask reactor. The experiment was conducted in a temperature range of 323 to 353 K with a catalyst concentration of 1.7 g/L. The results indicated that the reaction kinetics could be approached with a quasi steady state model and the chemical reaction on the catalyst surface was the determining step.

Key words: mathematical modeling, kinetics, determining step