Judul: Kajian Pengaruh Konsentrasi Metanol dan Lama Reaksi pada Proses Pemurnian Metil Ester Sulfonat terhadap Karakteristik Deterjen Bubuk
Abstrak: Soap and detergent have widely been used as cleaning product at various activities, such as laundry, warewashing, janitorial, domestic, transportation, commercial activity, and metal industry. One of important compiler substances in soap and detergent formulation is surfactant. According to Matheson (1996), there are four general types of surfactant namely anionic, nonionic, cationic, and amphoteric. Methyl ester sulfonates (MES) is one of anionic surfactant types, which have been being developed in recent years. Test in the laboratory indicates that biodegradation of MES (methyl ester sulfonates) is similar to AS (alcohol sulfate) and soap, but faster than that of LAS (linear alkylbenzene sulfonate). However, the problem is the sulfonation process still produces undesired sulfonated soap by-product, often called di-salt. Therefore, it is important to purify MES (methyl ester sulfonates) to reduce the content of di-salt in order to improve the performance of MES (methyl ester sulfonates) as surfactant. The aims of this research are knowing the differences of characteristics of unpurified MES and purified MES, obtaining the best condition purification process of MES, kno wing the effect of the purification process of MES on the characteristics of detergent powders and obtaining the best concentration of MES in the formulation of detergent powders. In this research, the purification process was done by addition of methanol at the certain concentration and reaction time. The effects of methanol concentration (factor K) and reaction time (factor t) were assessed in Completely Factorial Randomized Design with two factors. Each factor consisted of four levels (10, 20, 30 and 40 % for factor K and 30, 60, 90, and 120 minutes for factor t). The parameters measured on this step were pH, surface and interfacial tension, emulsion stability, foam stability, and detergency. Meanwhile, the effects of purification process on the characteristics of detergent powders were assessed in completely factorial randomized design with two factors that are the kind of MES (unpurified MES and purified MES) and MES concentrations. MES concentrations used in this design were 15, 20 and 25 %. The parameters measured on this step were pH, moisture content, bulk density, detergency, emulsion stability, water insoluble substance and whiteness. Based on the results, it showed that unpurified MES had the following characteristics: pH value of 4,98, surface tension 30,6 mN/m (46,36 %), interfacial tension 31,1 mN/m (87,99 %) to 34,70 mN/m (98,02 %), emulsion stability 15,96 %, foam stability 0,38 hours, and detergency 25,84 %. Meanwhile, the characteristics of purified MES were pH value of 3,95 to 4,93 (MES before neutralized) and 6,92 to 7,67 (MES after neutralized), surface tension 31,45 mN/m (47,72 %) to 42,25 mN/m (64,11 %), interfacial tension 31,85 mN/m (89,97 %) to 34,70 mN/m (98,02 %), emulsion stability 16,67 % to 84,52 %, foam stability 0,41 hours to 3,84 hours, and detergency 26,28 % to 87,22 %. Based on the results, it showed that methanol concentration 40 % and reaction time 90 minutes performed the best condition of purification process. The characteristics of MES obtained from this best condition were: pH value before neutralized 3,95 and after neutralized 6,92, surface tension 42,25 mN/m (64,11 %),
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