31 research outputs found
EFFECT ACTIVATION OF CHEMICAL AND PHYSICAL TO STRUCTURE AND ACTIVATED CARBON QUALITY FROM CHARCOAL OBTAINED BY PYROLYSIS OF COCONUT SHELL
Activation of coconut shell charcoal has been done by a combination of chemical
and physical activation to determine the effect of chemical activators and activation
temperature to changes in the chemical structure and the quality of activated carbon .
The study was conducted on charcoal coconut shell of pyrolysis results with variation of
concentration and immersion time ZnCl2 as an activator , respectively 0.5 to 2 M for 12
to 24 hours . Then proceed with the activation of physics in reactor the activation of the
temperature variation of 500 to 800 oC with CO2 gas flow rate 20 mL / min . Evaluation
of the chemical structure and the quality of activated carbon performed FTIR , SEM ,
specific surface area , total pore volume , and average pore with Brunauer - Emmett -
Teller ( BET ) . The results showed the results of the analysis of SPSS through
Cofficients test the concentration variables most affect to moisture content , ash content ,
and iodine absorption from temperature variable and time of activation . The best quality
activated carbon produced at a concentration of ZnCl2 of 1.5 M, 24 hours soaking time of
24 hours , temperature 800 oC and the activation time of 120 minutes . The results as
moisture content of 8.47 % , volatile matter content of 18.55 % , ash content 1.44 % ,
bonded carbon content of 80.01 % and iodine absorption of 769.74 mg / g . The results
of FTIR analysis showed the surface of activated carbon containing CO and CH bonds ,
and SEM analysis showed the number and diameter of pores increased with the higher
calcination temperature . Surface area ( BET ) of 359.286 m2 / g , pore volume of 1.984 x
10-1 cm3 / g and pore mean of 11.46 Ǻ
EFFECT ACTIVATION OF CHEMICAL AND PHYSICAL TO STRUCTURE AND ACTIVATED CARBON QUALITY FROM CHARCOAL OBTAINED BY PYROLYSIS OF COCONUT SHELL
Activation of coconut shell charcoal has been done by a combination of chemical
and physical activation to determine the effect of chemical activators and activation
temperature to changes in the chemical structure and the quality of activated carbon .
The study was conducted on charcoal coconut shell of pyrolysis results with variation of
concentration and immersion time ZnCl2 as an activator , respectively 0.5 to 2 M for 12
to 24 hours . Then proceed with the activation of physics in reactor the activation of the
temperature variation of 500 to 800 oC with CO2 gas flow rate 20 mL / min . Evaluation
of the chemical structure and the quality of activated carbon performed FTIR , SEM ,
specific surface area , total pore volume , and average pore with Brunauer - Emmett -
Teller ( BET ) . The results showed the results of the analysis of SPSS through
Cofficients test the concentration variables most affect to moisture content , ash content ,
and iodine absorption from temperature variable and time of activation . The best quality
activated carbon produced at a concentration of ZnCl2 of 1.5 M, 24 hours soaking time of
24 hours , temperature 800 oC and the activation time of 120 minutes . The results as
moisture content of 8.47 % , volatile matter content of 18.55 % , ash content 1.44 % ,
bonded carbon content of 80.01 % and iodine absorption of 769.74 mg / g . The results
of FTIR analysis showed the surface of activated carbon containing CO and CH bonds ,
and SEM analysis showed the number and diameter of pores increased with the higher
calcination temperature . Surface area ( BET ) of 359.286 m2 / g , pore volume of 1.984 x
10-1 cm3 / g and pore mean of 11.46 Ǻ
PENGARUH VARIASI WAKTU DAN KECEPATAN PENGADUKAN DALAM PEMBUATAN ETIL ESTER DARI MINYAK KELAPA
Penelitian ini bertujuan memperoleh etil ester yang optimum. Penelitian ini diawali dengan reaksi transesterifikasi antara minyak kelapa dan etanol dengan variasi waktu dan kecepatan pengadukan. Etil ester dianalisis dengan GC dan GC-MS. Hasil transesterifikasi optimum sebesar 76,48 % diperoleh pada rasio minyak kelapa/etanol/NaOH 1:2:0,02 (100 mL : 50 mL : 2 g) dengan kecepatan pengadukan 300 rpm. Kecepatan pengadukan dan waktu reaksi berturut-turut di atas 400 rpm dan 30 menit menghasilkan rendamen etil ester di atas 80 %. Kata Kunci : minyak kelapa, transesterifikasi, variasi waktu, dan kecepatan pengaduka
Pengaruh Konsentrasi Virgin Coconut Oil (VCO) Terhadap Stabilitas Emulsi Kosmetik dan Nilai Sun Protection Factor (SPF)
Penelitian ini bertujuan untuk mempelajari pengaruh konsentrasi Virgin Coconut Oil (VCO) terhadap stabilitas emulsi kosmetik dan nilai Sun Protection Factor (SPF). Emulsi kosmetik dibuat dengan melakukan variasi VCO pada konsentrasi 1-25% dan tanpa VCO sebagai kontrol. Sediaan emulsi kosmetik tersebut, diuji kestabilan emulsinya meliputi uji pH dan viskositas yang dilakukan selama 4 minggu penyimpanan, uji ukuran droplet, uji pemisahan fase dengan sentrifugasi, uji serapan UV dan dihitung nilai Sun Protector Factor (SPF). Hasil karakterisasi menunjukkan bahwa konsentrasi VCO mempengaruhi stabilitas emulsi kosmetik dan nilai SPF-nya. Semakin tinggi konsentrasi VCO dalam emulsi kosmetik maka pH dan viskositas emulsi cenderung semakin kecil, ukuran droplet semakin besar dan nilai SPF cenderung semakin tinggi. Emulsi kosmetik dengan konsentrasi VCO 7% merupakan emulsi kosmetik terbaik yang memiliki penampakan homogen, pH berkisar 6,94-6,96 dan viskositas 295 poise, sedangkan berdasarkan kriteria SPF, semua emulsi kosmetik yang diperoleh belum memenuhi standar sediaan emulsi kosmetik di Indonesia
Purwarupa Sistem Kendali Suhu dengan Pengendali PID pada Sistem Pemanas dalam Proses Refluks/Distilasi
Abstrak
Elemen suhu atau panas merupakan salah satu elemen yang penting dalam dunia industri maupun dalam kegiatan riset atau penelitian. Salah satunya adalah teknik refluks yang sering digunakan baik di industri maupun riset pada laboratorium. Elemen suhu merupakan elemen yang paling penting dalam proses refluks maupun distilasi, sehingga sangatlah penting dilakukan pengendalian suhu tersebut. Pada pengendalian yang manual dan konvensional menyebabkan ketidak stabilan suhu dan dimungkinkan terjadi banyak kesalahan (error). Sehingga dampak yang lebih lanjut adalah kualitas produk hasil proses refluks maupun distilasi yang kurang baik.
Oleh karena itu, penelitian ini membuat perancangan sistem pengendalian suhu secara otomatis menggunakan kontroler elektronik dengan mode pengendalian sistem tertutup yang tidak hanya memberikan nilai setpoint saja tetapi juga dengan umpan balik sehingga dapat mengontrol atau mengendalikan sistem dengan baik.
Tujuan dari penelitian ini adalah merancang bangun/purwarupa dari sistem pengendalian suhu (temperature) pada pemanas (heater) menggunakan kontrol PIDÂ untuk proses refluks/distilasi sehingga terjadi kestabilan suhu yang terjaga dan mengurangi nilai kesalahan (error).Hasil dari penelitian dapat diketahui bahwa sistem pengendalian suhu dapat menggunakan kontrol PID dengan metode Ziegler-Nichols dengan mode osilasi teredam. Penalaan parameter kontrol didapat dari rumus empiris yang disarankan metode Ziegler-Nichols.
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Kata kunci—suhu, kontrol PID, Ziegler-Nichols
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Abstract
 Temperature or heat element is one important element for the industry as well as in research activities. One is a refluxing technique that used both in industry or in research laboratories. Temperature element is the most important element in the process of distillation and reflux, so it is important to control the temperature. In the manual control and conventional causes temperature instability and possible numerous errors. Thus further impact the quality of the product of reflux and distillation processes that are less good.
Therefore, this study makes design automatic temperature control system uses an electronic controller with closed system mode which not only provides the setpoint value, but also with the feedback so that they can control system properly.
The purpose of this research is to design a prototype of the temperature control system using PID control on the heater for the reflux / distillation resulting temperature stability and reduces the value of the error.The results of the research is that the temperature control system can use PID control with Ziegler-Nichols method with damped oscillation mode. Tuning control parameters obtained from the empirical formula suggested Ziegler-Nichols method.
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Keywords— temperature, PID control, Ziegler-Nichol
Copper-and-Nitrogen-Codoped Zirconium Titanate (Cu-N-ZrTiO<sub>4</sub>) as a Photocatalyst for Photo-Degradation of Methylene Blue under Visible-Light Irradiation
Synthesis and characterization of copper-and-nitrogen-codoped zirconium titanate (Cu-N-ZrTiO4) as a photocatalyst for the degradation of methylene blue (MB) have been conducted. The main purpose of this research was to investigate the co-doping effect of copper and nitrogen dopants in ZrTiO4 as a photocatalyst for the photodegradation of MB. Titanium-(IV) tetraisopropoxide (TTIP) was dissolved into ethanol and mixed with aqueous zirconia (ZrO2) suspension containing 10% nitrogen (N) (w/w to Ti) from urea and various amount of copper as dopants. The calcination was performed at temperatures of 500, 700, and 900 °C. The composites were characterized using Fourier transform infrared spectrophotometer (FTIR), X-ray diffractometer (XRD), scanning electron microscopy with energy dispersive X-ray (SEM-EDX) mapping, and specular reflectance UV-Visible spectrophotometer (SRUV-Vis). The degradation of 4 mg L−1 MB solution was conducted for various irradiation times. Characterization shows a significant decrease of the ZrTiO4 band gap from 3.09 to 2.65 eV, which was given by the composite with the addition of 4% Cu and calcination of 900 °C. Cu-N-ZrTiO4 composite can degrade MB solution up to 83% after 120 min under the irradiation of visible light
Synthesis of Nickel-loaded Sulfated Zirconia Catalyst and Its Application for Converting Used Palm Cooking Oil to Gasoline via Hydrocracking Process
The synthesis of the nickel-loaded sulfated zirconia catalyst (Ni-SZ) and its application for the hydrocracking process have been carried out. This work has been conducted to determine the activity and selectivity from various Ni concentrations loaded on sulfated zirconia (SZ) in the hydrocracking of used palm cooking oil. The synthesis technique was preceded by sulfation of ZrO2 through incipient wetness impregnation method using H2SO4 solution and then continued with the impregnation of Ni via hydrothermal method employing NiSO4 · 6H2O precursor salt. The hydrocracking process was performed in a fix-bed microreactor at the optimum temperature (350 °C). The SZ loaded with 3 wt% of Ni (Ni-SZ 3) successfully produced the highest liquid product (44.25 wt%) and selectivity on gasoline (100 %). Besides, the gasoline fraction in the liquid product was dominated by unwanted aromatics compounds. The excellent performance of Ni-SZ 3 due to it has high acidity value, specific surface area, and Ni content
Cobalt Doping on Zirconium Titanate as a Potential Photocatalyst with Visible-Light-Response
Synthesis of cobalt-doped zirconium titanate (Co-doped ZrTiO4) as a potential photocatalyst with visible-light-response had been conducted. Materials used in this research were titanium tetraisopropoxide (TTIP) as a precursor of TiO2, ZrO2 as another semiconductor for coupling, and CoSO4·7H2O as the source of cobalt dopant. The composite was prepared by the sol-gel method with various cobalt contents and calcination temperatures. Composites with various Co dopant contents (0, 1, 3, 5, 7, and 9% (Co wt./Ti wt.)) were calcined at 500 °C for 4 h. In addition, the composite with 5% of dopant content was calcined at 700 and 900 °C to observe the influence of calcination temperature. All samples were characterized by using X-ray powder diffraction method (XRD), Fourier-transform infrared spectroscopy (FTIR), specular reflectance UV-Vis spectroscopy (SRUV), and scanning electron microscopy equipped with X-ray energy dispersive spectroscopy (SEM-EDS). Co-doped ZrTiO4 with the lowest bandgap (2.94 eV) was achieved in a sample containing 3% of cobalt content calcined at 500 °C
Visible-Light-Induced Photodegradation of Methylene Blue Using Mn,N-codoped ZrTiO<sub>4</sub> as Photocatalyst
Composites of manganese and nitrogen-codoped zirconium titanate (Mn,N-codoped ZrTiO4) had been synthesized by the sol-gel method as a visible-light responsive photocatalyst for the photodegradation of methylene blue (MB). Synthesis was conducted at 25 °C using titanium(IV) isopropoxide, zirconium oxide, urea, and manganese(II) chloride. Mn,N-codoped ZrTiO4 containing fixed 10% nitrogen dopant (wN/wTi) with various Mn dopant contents (2, 4, 6, 8, and 10% wMn/wTi) and calcination temperatures (500, 700, and 900 °C) had been investigated. All of the Mn,N-codoped ZrTiO4 exhibit a band gap within the visible range (2.51 to 2.74 eV). Photodegradation of MB was performed under visible light illumination for 120 min. The highest activity was achieved up to 7.7 µg L−1 min−1, which was obtained from Mn,N-codoped ZrTiO4 calcined at 500 °C containing 6% Mn and 10% N dopants
PENGARUH SUHU KALSINASI PADA SINTESIS Fe-DOPED TITANIUM DIOKSIDA DENGAN METODE SOL-GEL
The purpose of this research was to examine the influence of temperature
variations on Fe-doped titanium dioxide (Fe-TiO2) synthesis by sol-gel method as
a model of visible light responsive photocatalyst. Fe-TiO2 synthesis by sol-gel
method was deemed better than the Fe-TiO2 synthesis by impregnation method
through the reflux process. The Fe-TiO2 by sol-gel method was prepared by
mixing Titanium Tetraisopropoxide (TTIP) and ethanol in aquabides and
FeCl3·6H2O with the concentration of 2% w/w. The product was dried and
calcined at temperature of 300, 400, 500, 600 and 700 °C. As for experiment
control, Fe-TiO2 was synthesized by impregnation method through the reflux
process. Both of Fe-TiO2 samples were characterized by X-Ray Diffraction,
Fourier Transform Infrared (FTIR), and Diffuse Reflectance UV-Vis (DR-UV).
The XRD data showed that the Fe-TiO2 synthesized using sol-gel method
has a smaller crystal size (17,48 nm) than Fe-TiO2 were synthesized by reflux
method (40,14 nm). The result of FTIR analysis of both types of samples showed
that Fe was succesfully doped into the TiO2. The result of DR-UV analysis of
both of Fe-TiO2 showed an increasing in responsiveness to the visible light. As
the whole result it can be concluded that Fe can doped into TiO2 producing Fe-
TiO2 as a model of visible light responsive photocatalyst, either by sol-gel method
or impregation. The most effective method was the sol-gel method with
FeCl3·6H2O as a source of Fe at the calcination temperature of 600 ° C that
produced a crystal size of 17.48 nm and Eg value of 2.89 eV