PENGOLAHAN SURFAKTAN ANIONIK LIMBAH LAUNDRY DENGAN METODE KOAGULASI DAN FOTODEGRADASI; THE TREATMENT OF ANIONIC SURFACTANT IN LAUNDRY WASTEWATER BY COAGULATION AND PHOTODEGRADATION METHODS

Fifit Astuti, Endang Tri Wahyuni

2014 | Disertasi | PROGRAM STUDI S2 KIMIA

This research was conducted to study an effective method to decrease anionic surfactant concentration in laundry wastewater. The investigated method was coagulation by moringa oleifera seed powder as coagulant, photodegradation catalyzed by TiO2, and the combination of both methods. The coagulation process was carried out by mixing and stirring the wastewater with coagulant BKBM. In this method, the mass of coagulant, reaction time and pH of the system were also optimized. The photodegradation method of anionic surfactant in the wastewater was carried out by irradiating the mixture of the wastewater and TiO2 photocatalyst by UV-lamp. In this process, the influence of irradiation time and photocatalyst mass were studied. The combination of the two methods was performed at the optimum conditions of the each method. The concentration of anionic surfactant remaining in the waste after the process of coagulation and fotodegradation was measured by UV-Spectrophotometric method using methylene blue as complexing agent (MBAS) that follows the ISO 7875, 1996. The reseach results showed that the coagulation process with mass coagulant of 100 mg, stirring time of 11.75 min, and the pH systems of 7 gave the maximum result in decreasing anionic surfactant content from 168.64 mg/L to 2.26 mg/L. On the other hand, the phothodegration process showed that the decrease of anionic surfactants can be achieved up to only 6.38 mg/L when the photodegradation was done for 22 h using 50 mg of TiO2. The combination methods of photodegradation followed by coagulation results in a reduction of anionic surfactant content down to 1.89 mg / L. While the combination methods of coagulation-photodegradation reduce the content of the anionic surfactant down to 0.41 mg / L. This level of surfactant content meets the index quality regulated by the government, i.e. below 0.5 mg/L. From the result obtained, it can be recommended that the combination methods of coagulation-photodegradation can be apllied in the waste treatment of laundry.

Kata Kunci : Anionic surfactants, Coagulation, Moringa oleifera seed powder, Photodegradation, TiO2.