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PURWARUPA SISTEM KENDALI SUHU DENGAN PENGENDALI PID PADA SISTEM PEMANAS DALAM PROSES REFLUKS/DISTILASI Pratomo, Teguh Budi; Dharmawan, Andi; Syoufian, Akhmad; Supardi, Tri Wahyu
IJEIS (Indonesian Journal of Electronics and Instrumentation Systems) Vol 3, No 1 (2013): April
Publisher : IndoCEISS in colaboration with Universitas Gadjah Mada, Indonesia.

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (497.607 KB) | DOI: 10.22146/ijeis.3836

Abstract

AbstrakElemen 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 PID  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. Kata kunci?suhu, kontrol PID, Ziegler-Nichols 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. Keywords? temperature, PID control, Ziegler-Nichols
MULTIPLE REGRESSION ANALYSIS OF THE INFLUENCE OF CATALYST CHARACTERS SUPPORTED ON γ-AL2O3 TOWARDS THEIR HYDROCRACKING CONVERSION OF ASPHALTENE Trisunaryanti, Wega; Triyono, Triyono; Mudasir, Mudasir; Syoufian, Akhmad
Indonesian Journal of Chemistry Vol 4, No 1 (2004)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (178.247 KB) | DOI: 10.22146/ijc.21868

Abstract

Multiple regression study of the influence of catalyst's characters with ?-Al2O3 as a support, including acidity, specific area, average pore volume, average pore radius, Ni content, and Mo content the hydrocracking conversion of asphaltene has been conducted.A multivariable regression analysis method, including regression analysis and correlation analysis, was applied on this study. Using multivariable regression, the characters of catalyst was correlated together with the data of the asphaltene conversions. Furthermore, using this method, the characters of catalyst, which have the greatest influence on conversion, may be evaluated. The results showed that there was a high correlation between catalyst characters and hydrocracking conversion of asphalten (r = 0.983). It means that the conversion was 98.3% correlated with the catalyst characters. The value of the multivariable determination coefficient was 0.966, indicating that at least 96.6% variation on the conversions was determined by combination of catalyst characters on this research. From the parameter value of regression equation, it could also be known that average pore radius and specific surface area were the two characters that have the greatest influence on the hydrocracking conversion of asphalten.
Synthesis and Photoactivity of Fe3O4/TiO2-Co as a Magnetically Separable Visible Light Responsive Photocatalyst Kunarti, Eko Sri; Kartini, Indriana; Syoufian, Akhmad; Widyandari, Karolina Martha
Indonesian Journal of Chemistry Vol 18, No 3 (2018)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (462.766 KB) | DOI: 10.22146/ijc.26831

Abstract

Synthesis of magnetic photocatalyst, Fe3O4/TiO2-Co, with characterization and photoactivity examination have been conducted. The synthesis was initiated by preparation of Fe3O4 particles using coprecipitation method. The Fe3O4 particles were then coated with TiO2-Co at a various ratio of Fe3O4:TiO2 and concentration of Co(II) dopant. The Fe3O4/TiO2-Co was characterized by FTIR, XRD, TEM, SEM-EDX, VSM, and SR UV-visible methods. Photoactivity of the Fe3O4/TiO2-Co was carried out using methylene blue as a target molecule in degradation reaction within a batch system. By using optimum conditions, the degradation of methylene blue solution was performed under exposure to UV, visible light and dark condition. Results showed that the Fe3O4/TiO2-Co formation was confirmed by the presence of Fe3O4 and anatase diffraction peaks in the X-ray diffractogram. SR UV-Vis spectra indicated that the Fe3O4/TiO2-Co was responsive to visible light. Band gap energy of the Fe3O4/TiO2-Co with dopant concentration of 1; 5; 10 and 15% were 3.22; 3.12; 3.09 and 2.81 eV, respectively. The methylene blue solution can be well photodegraded at a pH of 10 for 210 min. The Fe3O4/TiO2-Co has the highest ability to methylene blue photodegradation with dopant concentration of 10% gave degradation yield of 80.51 and 95.38% under UV and visible irradiation, respectively.
FUEL PRODUCTION FROM LDPE-BASED PLASTIC WASTE OVER CHROMIUM SUPPORTED ON SULFATED ZIRCONIA Hauli, Latifah; Wijaya, Karna; Syoufian, Akhmad
Indonesian Journal of Chemistry Vol 20, No 2 (2020)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (15.755 KB) | DOI: 10.22146/ijc.45694

Abstract

The preparation, characterization, and catalytic activity test of sulfated zirconia (SZ) modified with chromium for the hydrocracking of LDPE-based plastic waste have been investigated. SZ was prepared by wet impregnation method using zirconia nanopowder (ZrO2) and H2SO4 solution. SZ was further modified with chromium (0.5, 1.0, and 1.5% wt.%) by refluxing in aqueous solution of Cr(NO3)3·9H2O, followed by calcination and reduction processes. The prepared catalysts were characterized by SEM-Mapping and TEM. Hydrocracking of LDPE-based plastic waste was conducted at various temperatures and various catalysts. In addition, the optimum catalyst was repeatedly used for the reaction to demonstrate the stability of the catalyst. Liquid products obtained by hydrocracking were characterized by GCMS. The results showed that the morphology of the prepared catalysts had different sizes and disordered shapes after the addition of sulfate and Cr. The effective temperature for hydrocracking was 250 °C. The highest selectivity to liquid product and gasoline fraction were 40.99 and 93.42 wt.%, respectively, and were obtained over Cr/SZ with 1.0 wt.% Cr. Hydrocracking of plastic waste over the used Cr/SZ catalyst with 1.0 wt.% Cr showed that the Cr/SZ catalyst was stable and reusable up to three repetitions.
Synthesis of Iron-Doped Zirconium Titanate as a Potential Visible-Light Responsive Photocatalyst Kurniawan, Rian; Sudiono, Sri; Trisunaryanti, Wega; Syoufian, Akhmad
Indonesian Journal of Chemistry Article in press
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (243.375 KB) | DOI: 10.22146/ijc.38616

Abstract

Synthesis and properties of iron-doped zirconium titanate (ZrTiO4) as a potential visible-light-responsive photocatalyst had been conducted. Various iron dopant concentration and calcination temperature were investigated toward the properties of Fe-doped ZrTiO4. The photocatalyst material was synthesized by sol-gel and impregnation method. Titanium tetraisopropoxide (TTIP) was used as a precursor, embedded on zirconia fine powder. A certain amount of iron (1, 3, 5, 7 and 9 wt.%) was introduced into the photocatalyst system from iron(II) sulfate heptahydrate (FeSO4·7H2O). Photocatalyst with various iron concentration calcined at 500 °C. ZrTiO4 with 5% iron additionally was calcined at 700 and 900 °C. Characterization was performed by using XRD, FT-IR, SR-UV, and SEM-EDX. The presence of iron on the surface of ZrTiO4 was proved by EDX analysis. Fe-doped ZrTiO4 with the lowest bandgap (2.83 eV) is 7% of iron content after calcination at 500 °C.
Synthesis and Characterization of Cu-Doped Zirconium Titanate as A Potential Visible-Light Responsive Photocatalyst Andita, Katarina Rachma; Kurniawan, Rian; Syoufian, Akhmad
Indonesian Journal of Chemistry Vol 19, No 3 (2019)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (14.502 KB) | DOI: 10.22146/ijc.39778

Abstract

Synthesis and characterization of Cu-doped zirconium titanateas a potential visible-light responsive photocatalyst had been conducted. Titanium tetraisopropoxide (TTIP) was used as a precursor of Ti source, reacted to ZrO2 powderand CuSO4·5H2O with various Cu concentrations of 0, 1, 3, 5, 7 and 9% (w/w) by sol-gel method. Zirconium titanate with Cu concentration of 5% was calcined at various temperatures of 500, 700 and 900 °C. All materials were characterized by using XRD, FTIR, SRUV, and SEM-EDX. The characterization proved that the materials were potential as a model of visible-light responsive photocatalyst. Composite with optimum bandgap energy (Eg) was obtained at 5% Cu content after 500 °C with an absorption edge wavelength of 431.93 nm and the bandgap of 2.87 eV.
PENGARUH VARIASI WAKTU DAN KECEPATAN PENGADUKAN DALAM PEMBUATAN ETIL ESTER DARI MINYAK KELAPA Jusman, Jusman; Setiaji, Bambang; Triyono, Triyono; Syoufian, Akhmad
KOVALEN: Jurnal Riset Kimia Vol. 4 No. 1 (2018): Edisi April
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (786.017 KB) | DOI: 10.22487/kovalen.2018.v4.i1.10188

Abstract

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 pengadukan
ZINC-DOPED TITANIA EMBEDDED ON THE SURFACE OF ZIRCONIA: A POTENTIAL VISIBLE-RESPONSIVE PHOTOCATALYST MATERIAL Alifi, Azizia; Kurniawan, Rian; Syoufian, Akhmad
Indonesian Journal of Chemistry ARTICLE IN PRESS
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (14.651 KB) | DOI: 10.22146/ijc.51172

Abstract

The preparation and characterization of zirconia-supported titania with a zinc dopant had been studied. Zinc-doped titania was grown on the surface of zirconia by the sol-gel method. Various zinc contents and calcination temperatures were applied to investigate the zinc doping effect and crystal structure of the zirconia-titania composite. X-ray diffraction method, Fourier-transform infrared spectroscopy, and UV-Vis reflectance spectroscopy were performed to characterize the composite. The morphology of the composite was observed by using a scanning electron microscope, and its composition was analyzed by using energy dispersive spectroscopy. Among various zinc dopant contents and calcination temperatures investigated, doping with 5% zinc (Zn wt./Ti wt.) at 900 °C calcination shows the best result in response to visible light with a bandgap of 2.87 eV and absorption edge wavelength of 432.61 nm.
COBALT DOPING ON ZIRCONIUM TITANATE AS A POTENTIAL PHOTOCATALYST WITH VISIBLE-LIGHT-RESPONSE Sulaikhah, Emilya Faridatul; Kurniawan, Rian; Pradipta, Mokhammad Fajar; Trisunaryanti, Wega; Syoufian, Akhmad
Indonesian Journal of Chemistry Vol 20, No 4 (2020): In Progress (1 August 2020)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (14.694 KB) | DOI: 10.22146/ijc.49459

Abstract

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.