Controllable Extinction Property of Au/SiO2 Nanocomposite Induced by Neutralization Reaction Time

The Au/SiO2nanocomposite was produced using surface active agent P123, and its optical absorption spectra was measured by spectrophotometer. It was found that the intensity of absorption peak was strengthened and underwent a red-shift as the neutralization reaction time extended. The variation of optical extinction property of one gold particle (GP) with different size had been investigated by Mie theory. It was found that the extinction property of the single spherical GP possessed an obvious size effect. The extinction property of Au/SiO2nanocomposite had been analyzed by Maxwell-Garnett (MG) theory. It showed that the extinction peak underwent a red-shift and the extinction intensity was strengthened when the size of gold nanoparticles (GNs) increased. The theoretical and the experimental results show that the extinction property of Au/SiO2nanocomposite changes because the scattering effect of GNs are strengthened when their sizes increased by controlling the neutralization reaction time.

Download Full-text

Studi Kinetika Reaksi Metanolisis Pembuatan Metil Ester Sulfonat (MES) Menggunakan Reaktor Batch Berpengaduk

Jurnal Teknik Kimia dan Lingkungan ◽

10.33795/jtkl.v1i1.23 ◽

2017 ◽

Vol 1 (1) ◽

pp. 28

Author(s):

Abdul Chalim ◽

Agung Ari Wibowo ◽

Ade Sonya Suryandari ◽

Muhammad Muhajjir Syarifuddin ◽

Moh. Tohir

Keyword(s):

Reaction Time ◽

Methyl Ester ◽

Reaction Temperature ◽

Batch Reactor ◽

Surface Active Agent ◽

Active Agent ◽

Acid Methyl Ester ◽

Operating Conditions ◽

Molar Ratio ◽

Surface Active

Surfaktan merupakan surface active agent yang banyak diaplikasikan dalam bidang industri kimia berkaitan dengan kemampuannya menstabilkan emulsi antara fasa minyak dan fasa air. Surfaktan berbasis minyak nabati merupakan pengembangan teknologi di bidang surfaktan yang selama ini didominasi oleh surfaktan berbahan baku minyak bumi. Metil ester sulfonat (MES) adalah surfaktan anionik yang dihasilkan melalui reaksi antara metil ester asam lemak dengan agen pensulfonasi atau yang lebih dikenal dengan reaksi sulfonasi. MES mengalami proses lanjutan yang disebut dengan reaksi metanolisis dan netralisasi. Penelitian ini mempelajari pengaruh rasio mol reaktan, waktu reaksi dan suhu reaksi terhadap yield MES pada reaksi metanolisis. Yield MES tertinggi yaitu 49,71% dicapai pada suhu reaksi 120°C, waktu reaksi 120 menit dan rasio mol MES terhadap metanol 1:3. Konstanta laju reaksi metanolisis ditentukan dengan mereaksikan reaktan di dalam reaktor batch berpengaduk pada kondisi operasi tersebut.Surfactant is a surface active agent which is widely applied in chemical industry related to its ability to stabilize the emulsion between the oil phase and the water phase. Surfactant-based on vegetable oil is a technology developed in the field of surfactant which has been dominated by surfactants made from petroleum. Methyl ester sulfonate (MES) is an anionic surfactant produced by the reaction between fatty acid methyl ester with a sulfonating agent or called as sulfonation reaction. MES undergoes an advanced process called methanolysis and neutralization reactions. This study investigated the effect of reactant molar ratio, reaction time and reaction temperature on MES yield on methanolysis reaction. The highest MES yield of 49.71% was achieved at a reaction temperature of 120°C, the reaction time of 120 minutes and the molar ratio between MES and methanol of 1:3. The rate constants of methanolysis reactions are determined by reacting the reactants in the stirred batch reactor under those operating conditions.

Download Full-text