Pengolahan cairan bekas proses pickling dengan ekstrak abu dan udara dalam reaktor tangki berpengaduk ditinjau dari segi kinetika reaksi

KUNDARI, Noor Anis, Prof.Dr.Ir. Ida Bagus Agra

2002 | Tesis | S2 Teknik Kimia

Cairan bekas proses pickling (CBPP) menimbulkan pencemaran lingkungan. Masalah ini diatasi dengan mereaksikan limbah itu dengan ekstrak abu dan udara, menghasilkan kalium sulfat yang dapat digunakan sebagai pupuk dan feri hidroksid yang dapat digunakan sebagai bahan pewarna. Reaksi CBPP dengan ekstrak abu dan udara dilakukan dalam reaktor tangki berpengaduk. Proses dilakukan secara batch dan alir. Proses batch dilakukan dengan mereaksikan CBPP dan ekstrak abu dengan perbandingan tertentu serta Qaliri udara dengan kecepatan tertentu. Cuplikan dlambil setiap selang waktu 15 menit, dan dihentikan setelah 120 menit. Proses alir dilakukan dengan cara, mula-mula reaktor diisi umpan awal ekstrak abu sejumlah tertentu, kemudlan dipanaskan sambil diaduk. Setelah suhu yang d&ehen& tercapai, dimasukkan umpan CBPP yang terlebih dahulu dipanaskan sehingga suhunya sama dengan umpan awal ekstrak abu. Bersamaan dengan itu dlalirkan umpan ekstrak abu, CBPP, dan udara dengan kecepatan tertentu. SeIama proses berlangsung, suhu dipertahankan dengan penangas air. Setelah keadaan ajeg tercapai, diambil cuplikan dan dianalisis untuk mengetahui kadar fero dan feri dalam cairan dan total &lam suspensi. Beradasarkan pengaruh suhu dan putarm pengaduk diketahui bahwa reaksi kimia dan prpindahan mass sama-sama mcngendalikan reaksi secara keseluruhan. Dalam kisaran variabel yang dipelajari, konstmte kecepatan reaksi dan konstante perpindahan massa masing-masing dipengardu oleh suhu- secara eksponensial, clan secam logaritmik oleh putariin pengaduk Pengolrihan hasil proses dilrrkukan dengan rnemisahkm endapan dan bcningan. Endapan dicuci dengan air dan dikeringkin, himudlan dipanaskan pada sufiu 350 "C. Beningan dipanaskan plan-plan ldu dikristalkan. Dari 500 cm3 suspensi dihasilkan 2,62 g serbuk Fe203 dan 1824 g hstal &SO4

The pickle liquid waste from the pickling process causes environmental pollution. This problem could be solved by reacting the waste with ash extract and air to produce KzS04 that can be used as fertilizer and ferric hydroxide, which can be used as pigments. The reaction between the pickle liquid waste, ash extract, and air was carried out in a stirred tank reactor, batch wise as well as continuousaly. The batch process was started with pouring the ash extract into the reactor and heated to the desired temperature. Then, heated waste was added, and at the same time air was bubbled from the bottom of the reactor. Samples were taken at 15 minutes intervals, until 120 minutes of reaction time. The continuous process was started with filling the reactor with ash extract and heated to the desired temperature. Then a certain quantity of heated waste and air with certain flow rate were introduced separately into the reactor, and stirred rigorousaly. During the process the temperature was kept constant using a water bath. After steady state was reached, samples were taken to determine the ferrous and ferric contents of the filtrate and the suspension. Based on effects of temperature and agitation, the rate of reaction and the mass transfer were simultaneously controlled the rate of the process. Within the range of variables studied, the reaktion rate constant and the mass transfer constant were affected by temperature exponentially and logarithmicaly by the agitation, respectively. Processing of 500 cm3 suspension produce 2,62 g of red pigments of Fez03 and 18,24 g of &SO4 crystal.

Kata Kunci : Kinetika Reaksi,Reaktor Tangki Berpengaduk,CBPP, waste pickle liquid - ash extract - stirred tank reactor - reaction rate - mass transfe