KECEPATAN PENYERAPAN ZAT ORGANIK VINASE DENGAN ECENG GONDOK KOMBINASI LUMPUR AKTIF

Limbah vinase dengan konsentrasi zat organik yang tinggi merupakan hasil samping produksi alkohol dari molase, berpotensi mencemari dan merusak lingkungan sehingga harus diolah sebelum dibuang ke lingkungan. Eceng gondok dimanfaatkan untuk pengolahan limbah vinase. Penelitian ini dilakukan untuk mendapatkan konsentrasi vinase maksimum di mana eceng gondok masih dapat tumbuh dan kecepatan penyerapan zat organik vinase menggunakan eceng gondok (Eichhornia Crassipes) dikombinasi lumpur aktif. Eceng gondok kombinasi lumpur aktif ditanam pada limbah vinase dalam bak berukuran 115 cm x 76 cm x 35 cm. Tinggi larutan vinase 31,5 cm. Massa eceng adalah sekitar 800 g. Larutan vinase diaduk menggunakan pompa agar homogen. Konsentrasi awal vinase antara 744 – 1880 mg/L. Setiap hari sampel diambil untuk dianalisis COD-nya, selama 8 hari Hasil penelitian menunjukkan bahwa eceng gondok dapat tumbuh pada vinase dengan konsentrasi COD maksimum 1894 mg/L. Dengan model yang diajukan, kecepatan penyerapan zat organik (RE ) oleh eceng gondok kombinasi lumpur aktif adalah S l r l E K C kXC V Cl M H k R + = + (mg/L)/jam, di mana nilai kr/H = 2,89x10- 6/(mg/L)jam. Cl adalah konsentrasi zat organik di larutan, H tetapan Henry, M massa eceng gondok, V volum vinase, dan X adalah konsentrasi lumpur aktif. Kecepatan penyerapan ini berlaku pada konsentrasi vinase berkisar antara 184 – 1880 mg/L dan X berkisar 504 -520 mg/L. Efisiensi penyerapan kombinasi eceng gondok dengan lumpur aktif sekitar 52,34 – 78,57%

Studi kesetimbangan ekstraksi asam laktat dalam air dengan pelarut murni

ABSTRAC The purpose of this work is to study the equilibrium on the extraction of lactic acid in aqueous solution with pure solvents of petroleum ether and kerosene. The study of the effect of different solvent on the extraction equilibrium of lactic acid in aqueous solution was carried out at ambient temperature. The parameter studied in this work was the total concentration of lactic acid in the aqueous phase. The result of this work is compared to the equilibrium data of lactic acid extraction using xylene obtained from the literature. From the three different solvents, kerosene is the best solvent to extract lactic acid from aqueous solution. The distribution coefficient increases with the increase of the total concentration of lactic acid in the aqueous phase for the extraction using all pure solvents studied in this work. The study of the effect of temperature on the extraction equilibrium showed that the higher the extraction temperature the lower the distribution coefficient of the extraction

Perpindahan panas pada alat penukar panas untuk menyimpan panas laten

ABSTRACT An experimental study to investigate the heat transfer rate and to calculate the total energy that can be stored in a heat exchanger for latent heat thermal energy storage system using the latent heat of fusion of a phase change material (PCM) has been carried out in this study. The heat storage container is a double pipe heat exchanger where the energy source fluid (hot water) flows through the inner tube (copper, of inside diameter of 12.5 mm, outside diameter of 16 mm and length of 149.5 cm), while the heat sink (storage PCM) fills the annular gap (outer tube made of PVC with inside diameter of 78 mm and thickness of 6 mm). The PCM used in this experiments is the paraffin wax with melting temperature of 44°C. Measurements were made of the temperature change of the hot water as well as of the paraffin wax. The heat transfer rate and the accumulative energy stored as a function of time was evaluated for different hot water flow rates and inlet temperatures. The melting rate of the PCM was also investigated visually. The experimental results with the parameter of hot water mass flow rates show that the heat transfer rate increases 181% at the time of 50 minutes from the initial process by increasing the hot water mass flow rate from 0.00764 kg/sec to 0.0221 kg/sec for the water inlet temperature of 70°C. The heat transfer rate at 50 minutes from the initial process for the experiment using hot water mass flow rate of 0.0221 kg/sec increases 97.2% by increasing the hot water inlet temperature from 60°C to 70°C. The accumulated energy stored at the PCM also increases by increasing the hot water mass flow rate for a constant inlet temperature and/or increasing the inlet temperature for a constant mass flow rate. The results of the visual investigation of the melting rate of PCM show that convection in the molten zone was found to be an important parameter affecting the heat exchanger performance

Pengukuran Titik Beku Larutan Asam Asetat-Asetamida

In this study, the freezing point of the acetic acid-acetamide system has been determined using a modified Beckmann freezing point apparatus throughout the entire range of concentration. The data obtained are compared to the data of the previous investigators. The results of the present work agree exellently with the data of the two other investigators for the acetamide concentration from 0 17701 % up to 30 mol % (Kremann et al., 1922Sisler et al., 1944). For the acetamide concentration more than 30 mol %, the results of the present work are still in good agreement with the data obtained by Sister et al. (1944), but a small discrepancies appears compared to the data of Kremann et al. (1922). The eutectic point obtained in this experiment is -11.2°C the at acetamide concentration of 30 mol %

Koefisien perpindahan massa keseluruhan volumetris pada kolom ekstraksi mixer-settler

BSTRAK The volumetric over-all mass transfer coefficient (K,.a) in a single stage mixer-settler column has been investigated. In the measurement of K,.a. acetic acid was extracted from kerosene-acetic acid solution into water. The mixer-settler column used in this experiment was divided into a mixer of 5.8 em height and a settler of 5.5 em height separated by a drop coalescer. The column diameter was 10.2 em. The diameter of drop coalescer was 5 em. I em in height. with the holes diameter of I mm. The values of K,.a were affected by the volumetric rates of the continuous and dispersed phases and also by agitation speed. These data can be correlated by Sh,. = 8.75 X /0,/11 Re.o.3/ Relf>2 Re/46 in the ranges of ReI\u27 of 149.18358.63. Red of 51.18-296.91. and Rei of 5.639.12-11.280.06 with the relative mean error of 11.32%. Keywords: volumetris, kolom ekstraksi, Mixer-Settle

Preparation and antibacterial activity of p-Anisyl ethyl fumarate and ethyl n-phenyl fumaramate

In order to generate potent C-9154 antibiotic derivatives, it has been conducted the synthesis and antibacterial activity evaluation of p-anisyl ethyl fumarate and ethyl N-phenyl fumaramate. These target molecules were chosen as the former would be a para-methoxy substituted C-9154 derivative, whereas the latter would be an example of unsubstituted C-9154 derivative bearing an amido-ester fumaric side chain.p-Anisyl ethyl fumarate was synthesized from p-anisaldehyde by reduction with NaBH4, condensation of p-anisyl alcohol with maleic anhydride, and esterification of the resulting p-anisyl maleic acid with ethanol in the presence of benzenesulfonic acid as the catalyst. These reactions gave satisfactorily yields (55-81 %) in all steps involved. In the case of ethyl Nphenyl fumaramate, this molecule was synthesized in 84 % yield through condensation of aniline with maleic anhydride, followed by esterification with ethanol in the presence of concentrated sulfuric acid.The antibacterial activity test showed that the minimum inhibition concentration (MIC) of p-anisyl ethyl fumarate and ethyl N-phenyl fumaramate towards Staphyllococcus aureus were 15 and 25 μg/mL. Interestingly, the MIC values of these two compounds towards Eschericia coliwere also 15 and 25 μg/mL respectively. Thus, the data showed that the two C-9154 derivatives obtained are sufficiently potent and possess antibacterial activities which are comparable to the antibacterial activity of C-9154 itself towards Staphyllococcus aureus (12.5 – 37.5 μg/mL) and Eschericia coli (25 – 50 μg/mL).Key words: synthesis, antibacterial activity, fumarate and fumaramate

Karakteristik Bio-Oil Hasil Pirolisis Ampas Tebu (Bagasse)

Bagasse is a waste of sugar mills that can be utilized for a variety of chemicals. The purposes of this study are to determine the percentage of the compounds and physical properties of bio-oil, to determine the effect of variations of particle size and heating rate on the yields of bio-oil. Pyrolysis has been carried out in a reactor made of steel pipe type 5737 with dimension: diameter 7.62 cm and length 37 cm in length. The reactor was inserted into the furnace with a diameter of 15.24 cm and a length of 40 cm. One hundred and fifty grams of bagasse (Saccarum oficinarum L) has been inserted into the reactor without the presence of oxygen at atmospheric pressure. Pyrolysis has been carried out at the particle size of (-20+25) mesh, (-25+30) mesh, (-30+35) mesh , (-35+40) mesh, and -40 mesh and electrical voltage of 100, 105, 115, and 120 volt. Produced bio-oil has the following properties: brown color, pH of 2.96 to 3.03, viscosity of 1.3306 to 1.5101 cp, and density of 1.03 to 1.5 g/mL. The largest content of the compound is acetic acid (59,72%). The highest yields percentage of the particle size is (40,32%) on (-20+25 mesh) and highest yields percentage electrical voltage is 38,82% on 105 volt

Absorpsi Co2 Dengan Larutan KOH Dalam Tangki Berpengaduk Dan Berbaffle

ABSTRAK This study investigates mass transfer coefficient and reaction rate constant in the absorption of CO2 into aqueous solution of KOH. The experiments were carried out by bubbling CO2 from the bottom of a stirred tank containing KOH solution. The inner diameter of the stirred tank was 14 cm and the depth was also 14 cm. The tank was equipped with 4 baffles each of 2.5 cm in width and 12 cm in height. The stirrer was a flat blade agitator of 5\u27cm in length and 1.5 cm in width. The sparger was made of copper pipe with the holes diameter of 1.5 mm. The effects of KOH concentration in the solution and operating temperature on mass transfer coefficient and reaction rate constant have been studied. The effect of KOH concentration (GB4O) on the mass transfer coefficient (K1) can be expressed as Kr, = 0.0001 7 In C7,0 + 0.01 79, in the range of CA0 of 0.0752 to 0.3445 gmol/L. The relative mean error for this expression is 1.92%. The correlation between the chemical rate constant acââ) with the operating temperature (T) is kâ,â = 107.exp (-11,501.75/RT), for the operating temperature of 303 to 333 K with the relative mean error of 3.78%. Keywords: Absorption, carbon dioxide, potassium hydroxide, stirred tank

Kinetika Adsorpsi Nikel (II) dalam Larutan Aqueous dengan Karbon Aktif Arang Tempurung Kelapa

The adsorption kinetics of nickel (II) in aqueous solution with activated carbon from coconut shell was studied by measuring the nickel concentration in the solution (C) as a function of time (t). The parameters studied in this study were adsorption temperature (T), particle diameter of activated carbon (d), and mass ratio of activated carbon to aqueous solution (r). It was found that the adsorption rate increased with the increase of the adsorption temperature and the mass ratio of activated carbon to aqueous solution. On the contrary, it was found that the rate of adsorption decreased with increasing the particle diameter of the activated carbon. ABSTRAKKinetika adsorpsi larutan nikel (II) dalam air dengan karbon aktif tempurung kelapa dianalisis dengan mengukur konsentrasi nikel pada larutan sebagai fungsi waktu. Parameter yang digunakan pada penelitian ini adalah suhu adsorpsi (T), diameter partikel karbon aktif tempurung kelapa (d), dan rasio massa karbon aktif tempurung kelapa dengan larutan nikel (II) dalam air (r). Hasil penelitian menunjukkan bahwa laju adsorpsi meningkat dengan bertambahnya suhu adsorpsi dan rasio massa karbon aktif tempurung kelapa dengan larutan. Sedangkan, laju adsorpsi menurun dengan bertambahnya ukuran diameter partikel karbon aktif tempurung kelapa

Koefisien Perpindahan Massa Pelarutan Padatan Dalam Tangki Berpengaduk dan Berpenghalang

ABSTRAK Mass transfer coefficients. of suspended particle.s were measured in atitated i\u27C.s.Ve/s. Three .sizes of agitated vessels. each with the diameters of 10.5, 14, and 16.8 cam were used. Granulated benzoic acid with the average diameter of 0.1 cm was dissolved into the aquadest. The effects of stirring Speed and vessel diameter on the 1)1055 transfer coefficients were studied. The correlation of mass transfer coefficients with the influence variables is espressed as Sh = 0.2286 Rep\u27" Sew in the ranges of Re of 147,910 to 1.006,240 and Sc of 1,101 to 1,127 with the relative mean error of 9.975%. Keywords: Massa Pelarutan Padatan, tangki pengadu