Articles

STUDI PENGGUNAAN KATALIS ABU SABUT KELAPA, ABU TANDAN SAWIT DAN K2CO3 UNTUK KONVERSI MINYAK JARAK MENJADI BIODIESEL Husin, Husni; Mahidin, Mahidin; Marwan, Marwan
REAKTOR Volume 13, Nomor 4, Desember 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (280.026 KB) | DOI: 10.14710/reaktor.13.4.254-261

Abstract

A STUDY ON THE UTILIZATION OF OIL PALM FIBRE AND FRUIT BUNCH ASH AND K2CO3 FOR CATALYTIC CONVERSION OF JATHROPA OIL TO BIODIESEL. Study on the use of coconut fiber ash, palm bunch ash and K2CO3 as the catalysts for conversion of jatropha oil into biodiesel using methanol solvent has been done. The biodiesel is produced by converting unpurified jatropha oil over catalyst through transesterification reaction. The catalysts are burned at temperature of 500, 600, 800 and 900oC for 10 hours. Transesterification reaction is conducted in three-neck flask at constant temperature of 60oC for 3 hours. The results showed that the unburned and burned coconut fiber ashes at 800oC catalysts give the highest biodiesel yield (87.05 and 87.97%) with low soap content (0.23-0.26%). The characteristic of biodiesel produced over those catalysts met the Indonesian and international quality standards, therefore those catalysts can be used as substitute for K2CO3 commercial catalyst.Abstrak   Studi penggunaan katalis abu sabut kelapa, abu tandan sawit dan K2CO3 untuk konversi minyak jarak menjadi biodiesel dengan pelarut metanol telah dilakukan. Biodiesel dibuat melalui konversi minyak jarak yang belum dimurnikan, menggunakan katalis, melalui reaksi transesterifikasi. Katalis-katalis tersebut dipijarkan pada temperatur 500, 600, 800 dan 900oC selama 10 jam. Reaksi dilangsungkan dalam labu leher tiga pada temperatur konstan 60oC selama 3 jam. Hasil penelitian menunjukkan penggunaan katalis abu sabut kelapa tanpa pemijaran dan dengan pemijaran pada 800oC memberikan perolehan biodiesel tertinggi (87,05 dan 87,97%) dengan kadar sabun rendah (0,23-0,26%). Karakteristik biodiesel yang dihasilkan dari penggunaan katalis-katalis tersebut ini telah sesuai dengan syarat mutu yang ditetapkan oleh Standar Indonesia dan Internasional, sehingga katalis-katalis tersebut layak digunakan sebagai pengganti katalis K2CO3 komersial
Mitigating Electricity a Price Spike under Pre-Cooling Method Marwan, Marwan; Pirman, Pirman
International Journal of Electrical and Computer Engineering (IJECE) Vol 6, No 3: June 2016
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (251.054 KB) | DOI: 10.11591/ijece.v6i3.pp1281-1293

Abstract

The growing demand for air-conditioning is one of the largest contributors to Australia overall electricity consumption. This has started to create peak load supply problems for some electricity utilities particularly in Queensland. This research aimed to develop a consumer demand side response model to assist electricity consumers to mitigate peak demand on the electrical network. The proposed model allows consumers to independently and proactively manage air conditioning peak electricity demand. The main contribution of this research is how to show consumers can mitigate peak demands by optimizing energy costs for air conditioning in a several cases such as no spike and spike considering to the probability spike cases may only occur in the middle of the day for half hour, one hour and one and half hour spikes. This model also investigates how air conditioning applied a pre-cooling method when there is a substantial risk of a price spike. The results indicate the potential of the scheme to achieve energy savings and reducing electricity bills (costs) to the consumer. The model was tested with the Queensland electricity market data from Australian Energy Market Operator and Brisbane temperature data from Bureau statistic during hot days.
Kinerja Katalis Paduan ZnO dengan Tembaga dan Logam-Logam Golongan VIII pada Steam Reforming Etanol menjadi Hidrogen Marwan, Marwan
Jurnal Rekayasa Kimia & Lingkungan Vol 7, No 2 (2009): Jurnal Rekayasa Kimia & Lingkungan
Publisher : Chemical Engineering Department, Syiah Kuala University, Banda Aceh, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (240.139 KB)

Abstract

Steam reforming of ethanol to H2 using ZnO catalyst with promotor metal, i.e. copper or metal group VIII (Pd, Pt and Ni) has been investigated. Catalyst’s performances are tested further at micro reactor operating at atmosphere pressure. Ethanol solution 20% is injected to reactor at rate of 2 ml/jam and is mixed with nitrogen flow at 25 ml/menit. XRD analysis shows active phases existence of each promotor for produced catalyst. Reaction product includes H2, CO2, and a nonidentified component. Selectivity of H2 fromation depends on chosen promotor metal types, where the selectifity decreases as follows: Pt > Pd > Cu ≈ Ni. Reaction temperature and promotor concentration also influence selectifity H2. For catalyst 1% Pd/ZnO and 1% Pt/ZnO, selectivity H2 was optimum at temperature reaction 450oC. Whereas Pd promotor concentration’s increasing from 1% to 5% improves H2 selectivity.Keywords: ethanol, hidrogen, steam reforming, ZnO
Water Quality Assessment in the Tsunami Areas of Banda Aceh Suhendrayatna, Suhendrayatna; Marwan, Marwan; Munawar, Edi; Zaki, Muhammad
Jurnal Rekayasa Kimia & Lingkungan Vol 7, No 1 (2009): Jurnal Rekayasa Kimia & Lingkungan
Publisher : Chemical Engineering Department, Syiah Kuala University, Banda Aceh, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (0.036 KB)

Abstract

Water quality assessment in the tsunami-affected areas conducted in Meuraxa and Kutaradja sub-districts in the area of Banda Aceh City. Water samples were collected in October 2006 from dug wells of tsunami-affected areas. These were characterized for various physical and chemical parameters. Water quality in the selected areas has shown that the surface water was contaminated due to the tsunami. Total Dissolved Solid, Total Suspended Solid, Acidity, and salinity were high in the affected areas indicating saline water intrusion into surface water tables. Dug wells in the highly affected locations showed higher values of heavy metal ions like Mn, Pb, Cu, Fe, Zn, and Cu compared to the reference points. No ion Hg was found in all samples. Keywords: Banda Aceh, heavy metals, tsunami, water quality
Simulasi Pengaruh Kandungan CO2 dalam Gas Umpan terhadap Reforming dan Shift Converter Sistem Pabrik Amoniak Yusuf, Jefry; Husin, Husni; Marwan, Marwan
Jurnal Rekayasa Kimia & Lingkungan Vol 10, No 4 (2015): Jurnal Rekayasa Kimia & Lingkungan
Publisher : Chemical Engineering Department, Syiah Kuala University, Banda Aceh, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (452.691 KB) | DOI: 10.23955/rkl.v10i4.3311

Abstract

Perubahan produksi dan pangsa pasar gas alam domestik maupun global mempengaruhi suplai terhadap pabrik pupuk-amoniak baik dari sisi jumlah, komposisi maupun harga. Kondisi ini memungkinkan pabrik amoniak menerima jenis gas alam berat kaya dengan CO2 (raw gas) maupun gas alam  ringan minim CO2 (treated gas). Pada penelitian ini telah dilakukan analisa pengaruh perubahan  komposisi gas alam terutama kandungan CO2 dengan variasi 0, 5, 10, 15, 20, 25, 30, 35, 40, 45 dan 50% vol terhadap operasional reforming dan shift converter sistem pabrik amoniak-2 PT. PI Mexisting dengan metodelogi simulasi mengggunakan Aspen HYSYS V8.0. Untuk memproduksi amoniak dengan jumlah yang sama, hasil studi menunjukkan penambahan CO2 dalam gas umpan akan meningkatkan pressure drop sistem, laju pembentukan komponen hidrogen turun sementara konsumsi energi bertambah di reforming, beban katalis shift converter dan beban feed gas compressor meningkat. Kandungan CO2 sebesar 7% vol masih mungkin diaplikasikan, mengingat ada batasan beban peralatan.
PENGARUH PEMBERIAN EKSTRAK BIJI JINTEN HITAM (Nigella sativa) TERHADAP KADAR GSH, MDA, JUMLAH SERTA FUNGSI SEL MAKROFAG ALVEOLAR PARU TIKUS WISTAR YANG DIPAPAR ASAP ROKOK KRONIS Marwan, Marwan; Widjajanto, Edi; Karyono, Setyawati
Jurnal Kedokteran Brawijaya Vol 21, No 3 (2005)
Publisher : Fakultas Kedokteran Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Cigarette smoke is the main risk factor of chronic  obstructive pulmonary disease (COPD). Several studies about COPD has focused on the oxidative stress in lung. Oxidative stress was related to inactivation of antiprotease enzymes, airway epithelial destruction and proinflammatory genes expression. Antioxidant may useful for treatment of COPD. Black seed (Nigela sativa) studies have showed that black seedhas antioxidant activity. The aim of this research  was to prove that black seed crude extract can protect wistar rat lung from oxidative stress which was caused by chroniccigarette smoke exposure. This experimental research used randomizedcomplete design with control group. Thirty wistar strain of Rattus novergicus, 2.5 to 3 months old, 150 – 250 grams ofweight were divided into five groups. First group  was used as negative control group (without any treatment), second group as positive control group (only cigarettesmoke exposure treatment), third group as cigarette smoke exposureand black seed crude extract dose 0.6 gr/kilogram  of body weight/day (group A), cigarette smoke exposure and  black seed crude extract dose 1.2 gr/kilogram of body weight/day (group B) and cigarette smoke exposure and black seed crude extract dose 2.4 gr/kilogram of body weight/day (group C). After 3 months five parameters were measured in this research.
MODIFIKASI MODEL PENJALARAN GELOMBANG MULTI ARAH Marwan, Marwan
MATEMATIKA Vol 12, No 1 (2009): JURNAL MATEMATIKA
Publisher : MATEMATIKA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (213.803 KB)

Abstract

In this paper we derived a modification of the model of waves evolution in two-directional spatial coordinates. Using KP equation as the basic model, we improved dispersive property in spatial x coordinate and named it as improved KP (iKP) equation. iKP has an exact dispersion relation in spatial x coordinate. Using this model, we derived second order regular waves and  analyzed the expression of Maximum Temporal Amplitude.  
HUBUNGAN PARAMETER KUAT GESER LANGSUNG DENGAN INDEKS PLASTISITAS TANAH DESA NEUHEUN ACEH BESAR Marwan, Marwan; Munirwan, Reza Pahlevi; Sundary, Devi
Jurnal Teknik Sipil Vol 3, No 1 (2013): Jurnal Teknik Sipil Volume 3, Nomor 1, September 2013
Publisher : Department of Civil Engineering, Syiah Kuala University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (157.154 KB)

Abstract

This research aims to evaluate effect of soil plasticity index (PI) to shear strength parameters, e.i. the angle of shearing (φ) and cohesion value (c). Parameters of φ and c obtained from Direct Shear Test in soil mechanics laboratory. The soil samples used for the research were taken from Neuheun Village, Mesjid Raya Subdistrict, and Aceh Besar District. Based on AASHTO soil classification, the soil sample is a Group A-7-6, whereas based on USCS soil classification, the soil is sandy clay of CL symbol. Soil specimen for Undisturbed Sample (UDS) and Disturbed Sample (DS) were 20 samples respectively, each sample was made to be three sub samples. The result of research shows that there is a linier correlation of shearing angle to PI, i.e., φ = -0,700 IP + 47,474, R2 = 0.882 for Undisturbed Samples (UDS) and φ = -1,757 IP + 59,313, R2 = 0.891 for Disturbed Samples (DS). The result of research also shows there is a linier correlation of cohesion value to PI, i.e., c = -0,053 IP + 1,569, R2 = 0.887 for UDS and c = -0,076 IP + 1,882, R2 = 0.783 for DS. It can be concluded that shear strength parameters for all tested samples in this research influenced by soil plasticity index. The higher soil plasticity index resulted the lower Shear Strength Parameters.
KORELASI Ø DAN C PADA UJI TRIAKSIAL DENGAN INDEKS PLASTISITAS TANAH DESA NEUHEUN ACEH BESAR Sundary, Devi; Marwan, Marwan
Jurnal Teknik Sipil Vol 2, No 3 (2013)
Publisher : Department of Civil Engineering, Syiah Kuala University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (163.912 KB)

Abstract

Abstract: This research aims to evaluate effect of soil plasticity index (PI) to shear strength parameters, e.i. the angle of shearing (φ) and cohesion value (c). The soil sample that to be used for the research was taken from Neuheun Village, Mesjid Raya Subdistrict, Aceh Besar District. Based on AASHTO soil classification, the soil sample was Group A-7-6, wereas based on USCS soil classification, the soil was sandy clay of CL symbol. Soil specimen for Undisturbed Sample (UDS) and Disturbed Sample (DS) were 20 samples respectively, each sample was made to be three sub samples. The result of research shows there is a linier correlation of shearing angle to PI, i.e., φ = -1,3783 PI + 34,345; R2 = 0,6939 for Undisturbed Samples (UDS) and φ = -1,7089 PI + 51,963; R2 = 0,7488 for Disturbed Samples (DS). The result of research also shows there is a linier correlation of cohesion value to PI, i.e., c = - 0,0952 PI + 2,5246; R2 = 0,7489 for UDS and c = -0,142 PI + 4,3785; R2 = 0,8741 for DS. It can be conclused that shear strength parameters for all tested samples in this research influenced by soil plasticity index. The higher soil plasticity index resulted the lower Shear Strength Parameters φ and c .Keywords : shear strength parameters, soil plasticity index, undisturbed and disturbed sampleAbstrak: Penelitian ini bertujuan untuk mengetahui hubungan nilai parameter kuat geser, yaitu: sudut geser (φ) dan nilai kohesi (c) dengan indeks plastisitas (Plasticity Index, PI) tanah. Tanah yang digunakan pada penelitian ini berasal dari Desa Neuheun Kecamatan Mesjid Raya Kabupaten Aceh Besar. Lokasi tersebut merupakan lereng gunung yang rawan terjadinya longsor. Kawasan ini telah digunakan sebagai sarana transportasi untuk menuju quarry yang terletak di ujung kawasan beberapa kompleks perumahan penduduk yang belum diketahui kekuatan daya dukung tanah dasarnya. Menurut klasifikasi AASHTO tanah Desa Neuheun tergolong jenis tanah lempung dengan simbol kelompok A-7-6, sedangkan menurut klasifikasi USCS tanah tersebut termasuk golongan tanah lempung berpasir dan diberi simbol CL. Pengujian kuat geser dilakukan dengan menggunakan alat uji Triaksial. Jumlah benda uji pada masing-masing tanah tidak terganggu (Undisturbed Sample, UDS) dan tanah terganggu (Disturbed Sample, DS) 20 sampel, tiap sampel dibuat menjadi tiga sub sampel. Hasil penelitian memperlihatkan bahwa hubungan nilai sudut geser dengan PI sampel tanah menunjukkan adanya hubungan linier dengan persamaan φ = -1,3783 PI + 34,345; R2 = 0,6939 untuk tanah UDS dan φ = -1,7089 PI + 51,963; R2 = 0,7488 untuk DS. Hubungan nilai kohesi dengan indeks plastisitas sampel tanah juga menunjukkan hubungan linier dengan persamaan c = -0,0952 PI + 2,5246; R2 = 0,7489 pada sampel tanah tidak terganggu dan c = -0,142 PI + 4,3785; R2 = 0,8741 pada sampel tanah terganggu. Dengan demikian dapat disimpulkan bahwa berdasarkan persamaan yang didapat dari hasil hubungan linier, nilai parameter kuat geser pada setiap lokasi pengambilan sampel tanah dipengaruhi oleh nilai indeks plastisitas tanah. Semakin tinggi nilai indeks plastisitas tanah maka nilai parameter kuat geser φ dan c semakin rendah.Kata kunci : parameter kuat geser, indeks plastisitas, tanah tidak terganggu dan terganggu.
Study of Seulawah Agam’s Geothermal Source Using Gravity Method Marwan, Marwan
Jurnal Natural Volume 14, Number 2, Year 2014
Publisher : Jurnal Natural

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (24.777 KB)

Abstract

Gravity method was carried out at Seulawah Agam Area to delineate the existence of geothermal source, which is specifically existed in both the geothermal filed of Heutsz’s Crater and Cempaga’s Crater. The Seulawah Agam is located in Aceh Besar district. Geologically, the area is dominated by volcanic mudflow and Lam Teuba’s rocks having age from Tersier to Resen Period. The equipment used includes Gravimeter CG-5 Autograv, Portable GPS (Global Positioning System), Navigation type (map of the survey area), computer and the other technical supports, such as handy talky, umbrella, watch, pens and observed data notes. This research was conducted by doing two stages. Firstly, establishing the base station which is a reference point for all gravity data measurements at each point. Secondly, measuring gravity data at each point by repeating three times following looping pattern as pathway of measurement either in Heutsz’s crater whose nine points recording or in Cempaga’s crater whose seventeen points. The data was simply processed using Microsoft Excel that can just plot the Bouguer anomaly and interpreted qualitatively due to preliminary research. The resultof this research has shown that both areas have two kinds of Bougeur anomalies which slightly attract attention who’s high and low anomaly. At Heutsz’s Crater has high and low density existed at F125 FR and B6 point. The Point whose high density means that it was formed mineralization by hydrothermal process through fracture materials, meanwhile the point whose low density indicates that there is existed the fault which is quite related to Seulimum’s Fault based on Aceh map. This result is also same as obtained at Cempaga’s Crater which means also same interpretation. In addition, it can be sum up that fault zones are essentially important in geothermal system that plays vital role in term of fluid circulation. Employing the gravity method in this research effectively can be said helpful proved by the Seulawah Agam has a good prospect become an alternative source of energy in the future.
Co-Authors A. Al Qahfi, Andi Sultan Abdul Ibrahim, Abdul Abel Tasman, Abel Adnan Rajak, Adnan Afrizal, Yuzuar Agus Indra Jaya Akmal Akmal Akmal, Nurul Asrillah Asrillah Bansu Irianto Ansari, Bansu Irianto Burhan, Rizqi A Cut Morina Zubainur, Cut Morina Cut Musriliani, Cut Darisma, Dian Darmadi Darmadi Dazrullisa, Dazrullisa Devi Sundary Devriany, Ade didik sugiyanto Duskri, M Edi Munawar Edi Widjajanto Elman, Andi Eti Indarti Fadhli Syamsudin Gartika Setiya Nugraha Hamzah, Dzikri Harjanto, Eric Hendra Susanto Hermanto, Koko Hidayati, Dian Mutia Husain Umar Husin, H. Husni Husin Ibnu Rusydy Ibrahim Ibrahim Ikhramullah, Oky Jefry Yusuf, Jefry jimi ronald, jimi Johan Matheus Tuwankotta Kurnia, Dimas Lailia Awalushaumi, Lailia Lancy Maurina, Lancy M. Ikhsan Mahidin Mahidin Mamika Ujianita Romdhini, Mamika Ujianita Masyitah, Masyithah Muhammad Dani Supardan Muhammad Isya Muhammad Kamal Muhammad Yani, Muhammad Muhammad Zaki Muhibbuddin Muhibbuddin Muhni, Akmal Mulia, Riki Andika Munirwan, Reza Pahlevi Munirwan, Reza Pahlevi Munirwansyah Munirwansyah Mutmainna, Mutmainna Naima Haruna, Naima Nani Suryani Nazariah, Nazariah Nazli Ismail Normalina Arpi Novieza, Novieza Nuraini Nuraini Nurhayati Nurhayati NURUL HIDAYAH Oesanna, Mieftah Pirman Pirman, Pirman Putra, Irfan Rifqan, Rifqan Rina Ratianingsih Rinaldi, Taufik Ristiliana Ristiliana Ruslan L Safrida, Ayu Said Hasan Samsul, Nur Malasari Setyawati Karyono Siraj Siraj Siti Rahmatullah, Siti Sitti Maryam Yasin, Sitti Maryam Sofyan M. Saleh Sri Milfayetty, Sri Suardi, Nurzahra Sugeng Raharjo Sugiarto Sugiarto Suhendrayatna Suhendrayatna Sulastri Sulastri Supriani, Fepy Susanti Alawiyah Sutopo Sutopo Syafaruddin Syafaruddin Syamsul Rizal Vadzla H, Laura Wahyu Rinaldi Wardani, Zenderi Yallo, Anjas Mukti Yusran Yusran Yusya Abubakar Zainal Abidin Zainal, Muzakir