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Zuchra Helwani
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Journal : Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains

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Pengaruh Variasi Kecepatan Putar, Temperatur Cetakan Dan Temperatur Tuang Terhadap Fluiditas Pengecoran Aluminium Kaleng Minuman Menggunakan Metode Qudong Andry Sutanto; Warman Fatra; Zuchra Helwani
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 5 (2018): Edisi 2 Juli s/d Desember 2018
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains

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Castability is a measur of the ability of an alloy to be formed according to the desired shape using a casting process, which is limited by fluidity. Qudong method 1999, used in this research with varying pouring temperature; 650oC, 700oC, 750oC, mold temperature; 100oC, 200oC, 300oC and cavity thickness; 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm. As an effort to increasing castability, this research giving a rotation to look the effect of variation mold temperature, pouring temperature and rotation. Fluidity increased with the increasing pouring temperature, mold temperatur and rotation. Fluidity increases with cavity thickness, maximum fluidity achieved at pouring temperature 750oC, mold temperature 300oC and rotation 1500rpm at 2.0-4.0 mm with a length of 120 mm and minimum fluidity can be filled with molten metal is at 0.5 mm with a length of 15.5 mm.Keywords : fluidity, molten aluminum cans, pour temperature, mold temperature, rotation.
Pemodelan Dan Simulasi Kinerja Downdraft Gasifier Menggunakan Teknik Minimisasi Energi Bebas Gibbs Rio Nanda Novendra; Zuchra Helwani; Sri Helianty; Zulfansyah Zulfansyah
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 1, No 1 (2014): Wisuda Februari Tahun 2014
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains

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Gibbs free energy minimization method has been used in modelling the performance of a downdraft gasifier. The performance is represented by the composition of resulting gas. Sixteen gases considered are H2, CO, CH4, H2O, CO2, N2, C2H2, C2H4, C2H6, NO, NO2, N2O, HCN, NH3, H2S and SO2. The simulation is carried out making used of EXCEL. The result showed that the predicted value of model fit reasonably well with experimental data. The model was also used to investigate the influence of biomass composition, oxidant ratio and composition of oxidizing agent to composition of the resulting gas. Three kinds of biomass considered are oil palm shell,oil palm frond and empty fruit bunch. The oxidant ratio simulated is varied from 0 to 1 while  composition of oxidizing agent is varied from 21% - 100% oxigen. The simulation result showed that those three parameters play an important role in gasification process which in combination can produce total H2 and CO up to more than 85%.Keyword : Gasification, modelling, downdraft gasifier, Gibbs free energy minimization
Penggunaan NI/NZA Sebagai Katalis Pada Proses Hidrodeoksigenasi Pirolisis Kulit Pinus (Pinus Merkussi Menjadi Bio-Oil Anna Apryana; Syaiful Bahri; Zuchra Helwani
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 3, No 1 (2016): Wisuda Februari Tahun 2016
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains

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Dependence on fossil fuels as an energy source brings us to the energy crisis. Therefore, it is necessary to reduce human dependence on non-renewable energy. One of them is to produce bio-oil from biomass are processed through hydrodeoxygenation pyrolysis technology. One type of biomass that can be used as raw material, namely energy sources pine bark which is a waste of the pine trees. This research aims to produce bio-oil from the bark of pine (pine merkussi) as an alternative fuel, studied the effect of the weight ratio of the catalyst Ni / NZA against biomass, studied the effect of impregnated metal Nickel (Ni) in Natural Zeolite deAluminated (NZA) and characterization of physical properties and the chemistry of the bio-oil is produced. Hydrodeoxygenation pyrolysis process is carried out at a temperature of 320 0C, silinap 500 ml, biomass 50 grams with a size of -100 + 200 mesh sieve, catalyst variation Ni / NZA of the biomass of 4%; 6% and 8% by weight and Ni metal impregnation variation of the Natural Zeolite deAluminated (NZA) of 0%; 1%; 2% and 3%. Results of this study produce bio-oil yields the largest on the use of the catalyst Ni / NZA 8% by weight of the metal content of 3% by 70.99%. Characterization of physical properties of bio-oil obtained in the form of density of 0.980 g / ml, 1,590 cSt viscosity, acidity 32.444 mg NaOH / gram sample, a flash point of 40 0C and calorific value of 44.509 MJ / kg. While the characterization of the chemical properties of bio-oil using Gas Chromatography-Mass Spectroscopy (GCMS) in the can several dominant chemical components such as acetic acid as much as 34.47%, 3-furaldehyde as much as 13.01%, 2-propanone as much as 12.46%, a 1.2-Ethanediol as much as 9:49% and 2-butanone as much as 6.26%.Keywords: Bio-Oil, Catalyst Ni/NZA, Hydrodeoxygenation Pyrolysis , Pine Bark
Sawit Off Grade Sebagai Bahan Baku Alternatif Pembuatan Biodiesel Melalui Proses Dua Tahap Menggunakan Katalis Zeolit Alam Yang Dimodifikasi Ayu Naluri; Hari Rionaldo; Zuchra Helwani
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 2, No 2 (2015): Wisuda Oktober Tahun 2015
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains

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Abstract

Palm off grade is a sort of CPO mill utilization which is not maximized. Palm off grade produced approximately 7-10% of the processing capacity of the plant CPO. Oil-palm off grade has a high free fatty acid contents, so it needs two stage process to produce biodiesel. The purpose of this research is to produce biodiesel with a maximum yield above 90%, determine the effectiveness of biodiesel production using a two-stage process with natural zeolite catalysts and determine the effect of temperature, mole ratio of oil : methanol and the concentration of catalyst to biodiesel yield. In this research, natural zeolite modified using 75% KOH solution. Then, biodiesel production have done in two stage, that was esterification and transesterification with variation of temperature (50°C, 60°C, 70°C), mole ratio of oil : methanol (1: 6, 1: 8, 1:10) and concentration of catalyst (2%-w, 4%-w, 6%-w) in transesterification. The highest yield of biodiesel is 96.99% at temperature 60°C, mole ratio of oil : methanol 1: 8 and concentration catalyst 4%-w. The result showed that the process conditions which influencing the yield of biodiesel is the reaction temperature and catalyst concentration.Keywords: biodiesel, natural zeolite, off grade palm oil, response surface methodology.
Proses Densifikasi Pelepah Sawit Menggunakan Gliserol Sebagai Filler Menjadi Bahan Bakar Padat Jimmy Anderson; Zuchra Helwani; Komalasari Komalasari
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 4, No 1 (2017): Wisuda Februari Tahun 2017
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Palm frond has been utilized only for raw source of animal feed, compost and organic fertilizer in plantation area. Oil palm fronds has calorific value of 15,184.05 kJ/kg with a density of 0.1383 g/cm3. Calorific value can be enhanced by densification. By biomass densification aims to increase density and decrease handling issue such as storage and transportation. The aims of this research is to produce solid fuel from palm fronds by densification process, to determine the characteristics of the product and to know the effect of gliserol as filler composition and pressing pressure in the processing by densification and also to know density, calorific value and proximate of product. The composition of gliserol filler used were 15%, 25% and 35%. Pressing pressure used were 50, 75 and 100 bar. The particle size used were < 850 μm. The highest density of the product is 1.07475 gr/cm3 was obtained at gliserol filler composition 35% and pressure 100 bar. The highest calorific value of the product is 16,928.12 kJ/kg was obtained at gliserol filler composition 35% filler and pressure 100 bar. The most affecting factor to caloric value and density are pressing pressure and filler composition.Keywords: calorific value, densification, density, filler, pressing pressure, palm fronds.
Karakterisasi Material Kemasan Pulp Cetak Tanpa Perekat Dari Pulp Batang Jagung Muhammad Rifki Aulia Rahman; Warman Fatra; Zuchra Helwani
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 2, No 1 (2015): Wisuda Februari Tahun 2015
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Molded pulp is an alternative packaging which has renewable and biodegradable properties. The use of molded pulp as packaging material still constrained due to the specific data that describes the characteristics of molded pulp has not widely publicized yet. This study was conducted to identify the characteristics of molded pulp as an alternative packaging material. Cornstalk was selected as raw materials which has abundant availabilty. Molded pulp packaging was manufactured by thermoformed methods. The thermoset nature of lignin in cornstalks would give possibilties in manufacture of molded pulp without using adhesive. The results showed the mechanical characteristics of binderless molded pulp from cornstalk pulp which have tensile index from 17.78 to 35.78 Nm/g, tear index from 9,25 to 26,09 mN.m2/g, and burst index from 0.901 to 1.5 kPa.m2/g. The effects of dependent variables on the mechanical properties of molded pulp were studied by statistical modelling using a polynomial second order. The empirical models were deduced to satisfactorily fit experimental data with the values of independent variables and allow to quantifiying the effects of each variables. The most influential factor on tensile and burst index of molded pulp was temperature of processing. Whereas, the processing pressure has greater influence on tear index of molded pulp.Keywords:material characterization; binderless, molded pulp; mechanical properties; statistical modelling.
Preparasi Pelepah Sawit Dengan Asam Oksalat Dan Pengaruhnya Terhadap Sifat Dan Morfologi Wood Plastic Composite Andreas Sahat Parsaulian; Bahruddin Bahruddin; Zuchra Helwani
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 2, No 1 (2015): Wisuda Februari Tahun 2015
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Reduced forest makes the availability of woods as the construction material on the wane. Oil palm frond has a potential to use to decrease utilization of woods directly. The main objective of this study was to evaluate the effect of oxalic acid and thermal pretreatment to morphology and properties of oil palm frond based wood plastic composite (WPC). The temperature of pretreatment were varied at 100oC, 120oC, and 140oC with submersion time 15 minutes. The mass ratio of oil palm frond sized 100 – 200 mesh as filler and polypropylene as a matrix is 30:70. 2% paraffin as plasticizer and 5% maleic anhydride polypropylene as compatibilizer were use as an additive. WPC samples were prepared using internal mixer Labo Plastomill at temperature 180oC and rotor speed 80 rpm. Testing experiments were prepared to mechanical testing consist of tensile and flexural strength and physical testing consist of density, water absorption, and swelling thickness. Scanning Electron Microscopy was used as a morphology testing. The result showed that oxalic acid pretreatment significantly gives an effect to mechanical and physical properties. The best WPC in this study was treated in the 120oC using oxalic acid based on tensile strength with 23.785 MPa, flexural strength 43.2 MPa, density 0.975 gr/cm3, water absorption 1.44%, and swelling thickness 0.17%.Keywords: pretreatment, oil palm frond, wood plastic composite
Sintesis Biodiesel Dari Minyak Nyamplung Menggunakan Katalis Geopolimer: Pengaruh Suhu Reaksi Transesterifikasi Dan Rasio Mol Minyak Terhadap Metanol Abdullah Syafi’i; Edy Saputra; Zuchra Helwani
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 5, No 1 (2018): Wisuda April Tahun 2018
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Petroleum reserves in Indonesia are increasingly depleted, requiring the use of alternative energy that is environmentally friendly and renewable like biodiesel. Biodiesel can be made by transesterification process of vegetable oils. Process of making biodiesel commonly use homogeneous catalyst which has the disadvantage the formation of by products such as complexity of the separation of catalyst. Therefore, in this study biodiesel was synthesized from calophyllum inophyllum oil by using geopolymer catalyst. Geopolymer catalyst is first synthesized by reacting sodium silicate, metakaolin, NaOH, and water. Several variations of the process variables were done to assess its influence on yield of biodiesel. The variables were used consist of a dependent variables and independent variables. The dependent variables were calophyllum inophyllum oil weight of 50 grams, 3%-wt of catalyst concentration, reaction time of 120 minutes, and stirring speed of 400 rpm, while the independent variables which variation molar ratio of oil:methanol 1:6 and 1:9 and variations of temperature 55 and 65 oC. Physical characterization were done including density 871 kg/m3, kinematic viscosity 4.38 mm2/s, acid number 0.41 mg-KOH/g biodiesel and flash point 140°C respectively accordance with the standards of Indonesian biodiesel (SNI 7182:2015).Keywords: biodiesel, catalyst, calophyllum inophyllum oil, geopolymer, yield
Pembuatan Bahan Bakar Padat Dari Pelepah Sawit Menggunakan Proses Torefaksi Pada Variasi Suhu Waktu Torefaksi Rina Maryenti; Komalasari Komalasari; Zuchra Helwani
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 4, No 1 (2017): Wisuda Februari Tahun 2017
Publisher : Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains

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Oil Palm Fronds can be used as alternative energy source by using torrefaction process. Oil Palm Fronds has a calorific value of 15439.39 kJ/kg. The calorific value can be increased by torrefaction. Torrefaction is a pre-treatment process of biomass into solid fuel within temperature range of 200 - 300 oC in an inert condition. This research aims to produce solid fuel from oil palm fronds and study the effect of variation in temperature and time torrefaction towards characteristic of solid fuel resulted. Torrefaction of oil palm fronds was using fixed bed horizontal reactor at temperature of 250 - 300 oC and time of 20 - 40 minutes. Product quality resulted was calorific value, mass yield, energy yield and proximate. The result obtained for calorific value in range was 18152.26 - 24060.32 kJ/kg, mass yield was 45.22 - 75.04 %, and energy yield was 70.49 - 88.23 %. Proximate analysis resulted in the form of moisture content was 3.42 - 5.44 %, ash content was 4.67 - 6.89 %, volatile content was 38.63 - 65.34 %, and fixed carbon was 24.55 - 51.06 %.Keywords: calorific value, energy yield, mass yield, oil palm fronds,torrefaction.
Pembuatan Biodiesel Dari Sawit Off-Grade Dengan Proses Dua Tahap Rahmawati Rahmawati; Zuchra Helwani; Yelmida A
Jurnal Online Mahasiswa (JOM) Bidang Teknik dan Sains Vol 2, No 2 (2015): Wisuda Oktober Tahun 2015
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Off-grade palm oil is a source of untapped vegetable oil. Off-grade palm oil can be used as an alternative raw material for biodiesel production despite having high content Free Fatty Acid (> 5%). Plant with a capacity of 30 tones of FFB yield 7-10% off-grade palm oil or 2-3 tons per hour. The catalyst used is potassium hydroxide because it has smaller ionization energy, making it faster to form a product when used as a catalyst. This research aims to produce biodiesel from low-quality raw materials and determine the effectiveness of the process by looking at the effect of process conditions such as reaction temperature, molar ratio and catalyst concentration on the yield of biodiesel. The biodiesel making process was carried out with two stages of the reaction, esterification and transesterification reactions due to high content of free fatty acid in the raw material. Data processing in this study was analyzed by response surface methodology (RSM) using Design Expert 8.0 program. Experiment runs were determined by central composite design (CCD), which consists of three variables, namely temperature, catalyst concentration and molar ratio of methanol to oil. The highest biodiesel yield was 88.56% (%wt) obtained under the conditions of reaction temperature 60 °C, the molar ratio of methanol to oil 8:1 and the concentration of 1% KOH base catalyst. The characteristics of biodiesel produced in the form of density, kinematic viscosity, acid number and flash point are in accordance with the standards of Indonesian biodiesel. Catalyst concentration have a significant influence on the yield of biodiesel.Keyword : off-grade palm oil, biodiesel, base catalyst, esterification and transesterification
Co-Authors Abdullah Syafi’i Adi Maulana Putra Ahmad Fadli Al Qohyum Fernando Andi Mulya Adha Andreas Sahat Parsaulian Andry Sutanto Anna Apryana Ari Wibowo Harahap Arief Maulana Ilham Arini Puspita Ramadhanti Ayu Naluri Bahruddin Bettry Rifani Dedi Meier Silaban Delvi Yolanda Desi Ivo Andri Ari Desly Fadilla Simbolon Dwi Yuni Ernawati Edi Susanto Edy Saputra Eferius Mendrofa Febrian Adhitya Febryanto Febryanto Firman Tampubolon Fitra Annisa Ganis Kharisma Wiranti Gusti Ayu Nurjanah Hari Rionaldo Heriza Saputri Heru Kristianto Holyness Nurdin Singadimedja Ida Zahrina Jhon Fery Marihot Tua S Jimmy Anderson Khairat Khairat Komalasari Komalasari M. Wahyu Nugraha Mery Christina Mia Afriyenti Mohd Fajri Amrullah Monika Shecilia Muh. Fadlan Alfuadi Muhammad Gus Iqbal Al-Pakningi Muhammad Rahman Muhammad Rifki Aulia Rahman Mustapa Ardi Nirmala Sari Nur Khairiati Qurotullaili Qurotullaili Ramdhani Asywal Ricfan Anggriawan Rina Maryenti Rio Nanda Novendra Rivo Fernando Romie Jhonnerie Romy Romy Rozanna Sri Irianty Sherly Oktarizona, Shinta Anggraini Silvia Reni Yenti Solly Aryza Sri Helianty Syafrima Wahyu SYAIFUL BAHRI Trisuciati Syahwardini Triyana Defi Vandhe Melsa Sembiring Viqrie Wahyudi Walter Valentino Sinaga Warman Fatra, Warman Wenny Susanty Widya Yoesepha Yelmida Azis Z Zulfansyah Zultiniar Zultiniar