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The Effect of Water Contents to Diesel Fuel-Water Emulsion Fuel Stability Suryadi, Joko; Winardi, Sugeng; Nurtono, Tantular
IPTEK The Journal for Technology and Science Vol 30, No 2 (2019)
Publisher : IPTEK, LPPM, Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (725.949 KB) | DOI: 10.12962/j20882033.v30i2.4997

Abstract

The declining world oil and gas reserves along with increasing gas emissions from fossil fuel consumption has received serious attention as an urgent problem worldwide. The alternative solution to the problem uses emulsified fuel which is expected to provide better combustion efficiency and will contribute to emission reductions, such as NOx and particulate matter (PM). The one of most important factor in emulsion fuel is its stability. In this work, the effect of water contents to stability of diesel-water emulsion fuels has been investigated. The stability of emulsion fuel related to coalescence and sedimentation formation. The diesel fuel-water emulsification process was carried out in a standard stirred tank consisting of a cylinder tank (93 mm in diameter) and Rushton disk turbine (40 mm in diameter). Materials used consist of diesel oil (Pertamina DEX), demineralized water, surfactants (Lecithin, Triton X-100 and Tween 80). The surfactant used is a mixture of Lecithin - Triton X-100 (76.6%: 23.4%) and Lecithin - Tween 80 (45.5%: 54.5%) at 1% total volume of emulsion. The impeller set in constant speed at 1900 rpm. To reduce emulsification energy consumption, water is added gradually into the tank at 2 mL/min of flowrate. Water content varies at 5%, 10%, 20%, and 40% by total volume of emulsion. Physical properties of emulsion fuel such as viscosity and density at room temperature were investigated periodically. The characterization of emulsion fuel stability was measured by slope value of absorbance ratio at wavelength 450 nm and 850 nm. Sediment formation was periodically by visual observation as emulsion phase percentage. Emulsion droplet size was measured by Dynamic Light Scattering (DLS) method. Physical properties of emulsions such as density and viscosity tend to constant value in order of time. Emulsion fuel with 5% water content has the largest volume of emulsion phase in the rest of time, 83 % for L-T emulsion fuel and 95% for L-Tx. The lowest slope value shown by 5% emulsion fuel water content, -8.657×10-5 for 5% L-T emulsion fuel and -2,084 × 10-4 for 5% L-Tx emulsion fuel. Droplet size measurement of emulsion shown that different amount of added water caused the different droplet size of emulsion.
RANCANG BANGUN SISTEM PENGOLAHAN AIR JERNIH DI KAMPUNG WISATA SABLON Rony Pasonang Sihombing; Agustinus Ngatin; Joko Suryadi; Retno Dwi Jayanti; Yunus Tonapa Sarungu; Robby Sudarman
Kumawula: Jurnal Pengabdian Kepada Masyarakat Vol 5, No 1 (2022): Kumawula: Jurnal Pengabdian Kepada Masyarakat
Publisher : Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/kumawula.v5i1.35907

Abstract

Air bersih yang memadai secara kuantitas, kualitas dan kontinuitas merupakan kebutuhan penting untuk kelangsungan hidup manusia. Oleh karenanya diperlukan suatu instalasi pengolahan air untuk menunjang kebutuhan ini. Air tanah merupakan air yang belum mengalami proses pengolahan dengan kriteria kualitas air yang sudah mendekati air bersih. Metode pengolahan air yang dilakukan menggunakan metode filtrasi fisik dan kimia sebelum digunakan untuk kebutuhan sehari-hari. Jenis filter yang digunakan adalah filter benang ukuran 10 µm, filter polipropilen (PP) 10 µm  dan filter karbon aktif. Berdasarkan hasil rancangan, air yang dihasilkan pada sistem rancang bangun diantaranya adalah air dengan kualitas kesadahan 2.3 NTU, masa pakai filter benang 14 hari/bulan, filter PP 2.4 hari/bulan, dan filter karbon aktif 30 hari/bulan. Untuk kemudahan operasional, sistem rancang bangun untuk filter PP dibuat paralel 3 agar perawatan dapat dilakukan setiap minggu.
Isolasi dan Pemurnian Protein dari Lembaga Jagung (Corn Germ) Menggunakan Metode Presipitasi dan Dialisis: Protein Isolation and Purification from Corn Germ Using Precipitation and Dialysis Methods Nancy Siti Djenar; Joko Suryadi
KOVALEN: Jurnal Riset Kimia Vol. 8 No. 1 (2022): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2022.v8.i1.15790

Abstract

The protein contained in corn germ can be used as a raw material that has the potential to provide many benefits in the food, pharmaceutical, and plastic industries. Corn germ with the highest content of protein is around 12-18.4%. In this study, protein from corn germ was isolated and homogenized using tris buffer HCl at pH 7.2. To obtain the protein fraction, precipitation was carried out (salting-out) using a solution of (NH4)2SO4 with saturation levels of 25%, 50%, and 70% respectively. The purification process was carried out by dialysis for 24 hours. The dialysis produced pure protein with a concentration of 4.161%. Based on the identification of functional groups using an FT-IR spectrophotometer, it was shown that the isolated and purified corn germ protein contained four absorption bands, including amide A (3211.48 cm-1 and 3226.91 cm-1), amide I (1633 cm-1 and 1629.85 cm-1), amide II (1527 cm-1 and 1552.70 cm-1) and amide III (1296.16 cm-1). The four absorption bands correspond to the wavenumbers of corn protein stated in the literature and are estimated to contain albumin, globulin, glutelin, and zein.
Perbandingan Efektivitas Ampas Teh Hitam dan Ampas Teh Hijau sebagai Adsorben Ion Logam Cr (VI) Rahma Gurroh Muhajjalin; Inayah Agawijaya; Budi Santoso; Joko Suryadi
Jurnal Kimia Fullerene Vol 6 No 2 (2021): Fullerene Journal of Chemistry
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.37033/fjc.v6i2.327

Abstract

Industrial waste contains various hazardous chemical compounds, such as heavy metals, one of which is chromium hexavalent ion, Cr (VI). Cr (VI) ion is carcinogenic and has toxic effects on humans. A study to treat Cr (VI) ion waste by adsorption using tea dregs has been carried out. Two types of tea dregs, black tea and green tea dregs are used as adsorbents, to compare their adsorption effectiveness. Adsorption effectiveness was determined using the visible-spectrophotometer. Parameters such as pH, adsorbent mass and concentration of Cr (VI) ions were optimized. Study determination of the adsorption isotherm model for each tea dregs included. The results showed that black tea dregs produced greater effectiveness than green tea dregs, with optimum adsorption conditions at pH 2, adsorbent mass of 0,8 grams and Cr (VI) ion concentration of 100 ppm with 99,50% removal efficiency. Meanwhile, green tea dregs produced the optimum adsorption conditions at pH 2, adsorbent mass of 0,4 grams and Cr (VI) ion concentration of 50 ppm with 87,49% removal efficiency. Langmuir adsorption isotherm model is fit for adsorption process by black tea dregs, meanwhile, green tea dregs fit with Freundlich and Langmuir isotherm model.
Pengaruh Ukuran Adsorben Kulit Pisang Kepok terhadap Penurunan Nilai Asam Lemak Bebas Minyak Goreng Bekas Joko Suryadi; Endang Widiastuti; Mohammad Idris Asyraf Ali; Zulfany Ali
Fluida Vol 12 No 2 (2019): FLUIDA
Publisher : Jurusan Teknik Kimia, Politeknik Negeri Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35313/fluida.v12i2.1616

Abstract

Penelitian ini bertujuan untuk mengukur tingkat perbaikan kualitas terhadap jelantah yang dapat dilakukan kulit pisang kepok. Minyak jelantah yang digunakan dalam penelitian ini diperoleh dari penjual gorengan dan didiamkan selama 24 jam sebelum diproses lebih lanjut. Metode adsorpsi yang akan dilakukan dalam penelitian ini adalah metode batch pada temperature 40 oC dengan waktu kontak pada 30 dan 60 menit. Kecepatan pengadukan diatur pada 500 rpm. Ukuran adsorben divariasikan pada 35, 60, dan 230 mesh. Karakterisasi yang dilakukan pada adsorben adalah kapasitas adsorpsi dengan variasi massa menggunakan metode iodin. Parameter kualitas jelantah adalah persen perubahan nilai asam lemak bebas sebelum dan sesudah perlakuan adsorpsi. Karakteristik kulit pisang sebagai adsorben dengan efisiensi terbesar ditunjukkan pada kulit pisang pada ukuran 230 mesh sebanyak 2 gram sebesar 73,38%. Persentase penurunan asam lemak bebas terbesar ditunjukkan pada kulit pisang pada ukuran 35 mesh dengan pengadukan selama 60 menit dengan nilai 8,57%.
Pengaruh Penambahan Minyak Zaitun Terhadap Karakteristik dan Reologi Edible Film Berbahan Dasar Gluten: The Effect of Addition of Olive Oil on The Properties and Rheology of Gluten-Based Edible Films Nancy Siti Djenar; Joko Suryadi; Nisa Siti Nursaadah; Erina Putri
KOVALEN: Jurnal Riset Kimia Vol. 8 No. 2 (2022): August Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2022.v8.i2.15948

Abstract

Gluten vegetable protein can be used as an alternative source of biopolymer as the basic material for edible film other than polysaccharides. Gluten-based edible films have a poor water vapor barrier and high cohesive and viscoelastic properties, therefore the addition of lipids and plasticizers is required. In this study, olive oil was added to reduce its permeability to water vapor, while glycerin was added to produce a more flexible edible film. The results showed that the addition of 1% olive oil could reduce the lowest water vapor transmission rate of 9.14 g/m2/24 hours with a thickness of 0.248 mm, tensile strength of 16.64 mPa, and elongation of 419.5%. The four characteristics are in accordance with the Japanese Industrial Standard. The antimicrobial testing on edible films showed that the addition of 0-2% olive oil could inhibit the growth of E. coli, while A. niger and R. oryzae 0-2% olive oil could not inhibit the growth of the two fungi. The measurement of optical properties showed that the transparency of the edible film was highest at the addition of 0% olive oil at 55%. The highest opacity value was with the addition of 1% olive oil, which is 2.96. The Fourier Transform Infrared (FTIR) identification showed that the edible film added with 1% olive oil had three characteristic absorption bands from gluten, olive oil, and an absorption band from glycerin. These bands indicate that olive oil, glycerin, and gluten do not react but only physically interact. The measurement using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometer (EDS) showed that the microstructure of gluten-based edible film produces a varied structure where the gluten structure network can be clearly observed and contains elements of C, O, N where the intensity of C and O elements of 160-400 cps and 30-100 cps, respectively.
Pembuatan dan Penentuan Nilai Efisiensi Sel Surya Berpewarna Tersensitisasi dengan Senyawa Antosianin dari Buah Manggis (Garcinia mangostana L.) sebagai Pewarna Pensensitisasi Joko Suryadi; Gunawan Gunawan; Abdul Haris
Jurnal Kimia Sains dan Aplikasi Vol 13, No 3 (2010): Volume 13 Issue 3 Year 2010
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (657.035 KB) | DOI: 10.14710/jksa.13.3.88-94

Abstract

Telah dilakukan penelitian mengenai pembuatan dan penentuan nilai efisiensi DSSC dengan senyawa antosianin dari kulit buah manggis sebagai pewarna pensensitisasi. Penelitian ini bertujuan untuk membuat rancangan DSSC, mengkarakterisasi penyusunnya dan menentukan nilai efisiensinya. Penelitian dilakukan dengan pembuatan elektroda kerja (working electrode) dari lapis tipis TiO2 yang mengadsorb antosianin kulit buah manggis, elektroda perlawanan (counter electrode) dari karbon dan elektrolit I-/I3- sebagai pasangan redoks. Karakterisasi DSSC meliputi kristalinitas TiO2, ukuran rongga dan ketebalan lapis tipis TiO2, serapan panjang gelombang maksimum zat pewarna, analisis gugus fungsi antosianin serta ikatan antara TiO2 dengan molekul antosianin. Nilai efisensi DSSC ditentukan dengan metode kurva arus dan tegangan. Hasil penelitian menunjukkan karakterisasi masing-masing penyusun DSSC telah memenuhi syarat sebagai rancangan DSSC dan nilai efisiensi rancangan DSSC adalah sebesar 2,2 x 10-3 %.
Karakter Ikatan Kimia, Kristalinitas, dan Ukuran Partikel Produk Silika yang Disintesis dari Bahan Limbah Padat Geotermal Joko Suryadi; Sabinna Azahra Sulaeman; Shafira Yulianthina; Tifa Paramitha; Eko Andrijanto
JC-T (Journal Cis-Trans): Jurnal Kimia dan Terapannya Vol 7, No 1 (2023)
Publisher : State University of Malang or Universitas Negeri Malang (UM)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17977/um0260v7i12023p010

Abstract

Silika disamping dapat disintesis dari prekusornya, juga dapat diekstraksi melalui bahan-bahan alam salah satunya adalah dari limbah padat geothermal pada situs pembangkit listrik panas bumi. Pada penelitian ini, telah dilakukan sintesis senyawa silika dari bahan baku limbah padat geothermal dengan metode sol-gel. Tujuan dari penelitian ini adalah memperoleh senyawa silika dari limbah padat geothermal dengan variasi implementasi penambahan HCl dalam metode sol-gel yaitu dengan metode tetes dan metode alir. Produk silika yang terbentuk kemudian dikarakterisasi berdasarkan ikatan kimia, kristalinitas, dan ukuran partikelnya. Bahan HCl yang digunakan dalam penelitian ini divariasikan pada tingkat kemurnian pro analis (p.a) dan teknis. Produk silika yang didapatkan mempunyai yield 25,74% dan 9,93% untuk masing-masing metode tetes dan metode alir. Karakterisasi produk silika yang dihasilkan mencakup analisis FTIR untuk karakter ikatan senyawa, difraksi sinar X untuk karakter kristalinitas dan metode dynamic light scattering untuk menentukan ukuran partikel produk. Karakteristik ikatan kimia dari analisis serapan bilangan gelombang dengan FITR menunjukkan bahwa produk yang dihasilkan adalah silika. Senyawa yang didapatkan berjenis amorf bersasarkan kristalinistasnya dengan ukuran partikel terbesar pada 483,5 nm dengan penambahan HCl dengan metode alir dan 782,5 nm dengan metode tetes.
Pengaruh Temperatur Kalsinasi Terhadap Kapasitas Ion Katalis Asam Heterogen Berbasis Silika dan Aplikasinya pada Sintesis Metil Oleat: The Effect of Calcination Temperature on the Ion Capacity of Heterogeneous Silica-Based Acid Catalysts and Its Application in the Synthesis of Methyl Oleate Joko Suryadi; Nanda Nabila; Syafa Neiska Bayhaqi; Eko Andrijanto
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 2 (2023): August Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i2.16457

Abstract

Sulfated silica catalyst is a solid acid catalyst which in its application is used to accelerate esterification reactions. The purpose of this study was to determine the effect of calcination temperature and increasing the amount of catalyst on the effectiveness of silica as a catalyst in the formation of methyl oleate through esterification reactions. The synthesis of sulfuric acid catalyst from rice husk ash went through several stages, including preparation of raw material for rice husk ash, production of silica using the sol-gel method, manufacture of silica-based acid catalysts and characterization of the sulfated silica catalyst. The acid catalyst was prepared using impregnation method with sulfuric acid and calcined at various temperatures of 500, 600, 700 and 800oC. The characterization of the acid catalyst formed includes ionic capacity, catalyst performance in the esterification reaction, and the determination of the bond characteristic functional groups using FTIR. The results of ion capacity analysis showed that the highest acidity value was found in the sulfated silica catalyst calcined at 600oC of 0.372 mmol/gram. Testing the performance of the catalyst in the esterification reaction with a ratio of 4:1 (methanol:oleic acid) obtained an ester conversion of 38.89% using a catalyst of 30% of the amount of oleic acid. Identification results using FTIR show that sulfate ions have chemically interacted with silica at around 1103.28 cm-1
Studi Awal Sintesis ZnO/SiO2 dengan Silika dari Limbah Padat Geothermal dan Uji Performansinya dalam Penghilangan Metilen Biru : Preliminary Study of ZnO/SiO2 Synthesis with Silica from Geothermal Solid Waste and Its Performance Test in Methylene Blue Removal Tifa Paramitha; Joko Suryadi; Rahma Ardelia Raissa; Teguh Aditya Nugraha; Nirmala Utami
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 3 (2023): December Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i3.16557

Abstract

Industrial development impacts environmental problems, such as the emergence of wastewater containing methylene blue. In this research, SiO2 was composited with ZnO to remove methylene blue. The steps of this study include SiO2 extraction from geothermal solid waste, ZnO/SiO2 synthesis, and methylene blue removal test. The process of extracting SiO2 from geothermal solid waste used the sol-gel method. The FTIR analysis showed that SiO2 contains siloxane group (Si-OH) and silanol group (Si-O-Si). ZnO/SiO2 synthesis was done by making SiO2 suspension and continued with adding the addition of several Zn(NO3)2.6H2O. The FTIR analysis of ZnO/SiO2 showed no absorption at the wavenumber 960 cm-1 and there is a shoulder around the number 950 cm-1 which indicates the vibration of Si-O-Zn. Meanwhile, methylene blue removal tests were carried out on artificial wastewater. Based on the research results, the highest percent removal (99%) was obtained under operating conditions, including a dose of 500 mg/L, pH 10, and contact time of 30 minutes. Based on box-benkhen analysis, it is known that dose and pH singularly affect the percent removal, while contact time does not affect the percent removal. The optimization results obtained optimum conditions for methylene blue removal at a dose of 581.952 mg/L, pH of 10, and contact time of 30 minutes. Percent removal in conditions without irradiation and with irradiation of UV light were 98.758% and 99.178%. It shows that the adsorption process is the main process in removing methylene blue, while the photocatalytic process has little effect because it is possible that only a small amount of ZnO can attach to the surface of SiO2.