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PEMILIHAN ADSORBEN UNTUK PENJERAPAN KARBON MONOKSIDA MENGGUNAKAN MODEL ADSORPSI ISOTERMIS LANGMUIR

REAKTOR Volume 14, No. 3, APRIL 2013
Publisher : Dept. of Chemical Engineering, Diponegoro University

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Abstract

ADSORBENT SELECTION FOR CO ADSORPTION USING LANGMUIR ISOTHERMIC ADSORPTION MODEL. The objective of this research is to choose the adsorbent that can be applied to decrease toxicity level and to purify fire smoke. In case of fire, toxicity level is high due to carbon monoxide. Adsorbent is chosen based on its ability to adsorb carbon monoxide using volumetric method in constant temperature. Materials to be tested are natural zeolite, active carbon, TiO2, CuO, MgO. Due to existence of organic and mineral polluters, natural zeolite needs to be activated prior to adsorption test using fluoride acid (HF), chloride acid (HCl), ammonium chloride (NH4Cl) and followed by calcination process. Result shows that activation of natural zeolite can increase Si/Al ratio and surface area. According to Langmuir adsorption model obtained, adsorption capacity of active carbon and natural zeolite are the highest. At 1 atmospheric pressure, adsorption capacity are 0.0682 mmol/g for active carbon, 0.0464 for activated natural zeolite with particle size of 400 nm, and 0.0265 mmol/g for activated natural zeolite with particle size of (37-50) μm. Penelitian ini bertujuan untuk memilih adsorben yang dapat diaplikasikan untuk menurunkan tingkat racun dan menjernihkan asap kebakaran. Pada kasus kebakaran tingkat racun asap disebabkan tingginya kandungan karbon monoksida. Proses pemilihan adsorben dilihat pada kemampuan adsorben mengadsorpsi karbon monoksida, yang dilakukan dengan metode volumetrik pada temperatur konstan. Material yang diuji adalah zeolit alam, karbon aktif, TiO2, CuO, MgO. Zeolit alam banyak terdapat pengotor baik organik maupun mineral, oleh karena itu sebelum dilakukan uji adsorpsi, zeolit alam terlebih dahulu diaktifasi menggunakan larutan asam florida (HF), asam khlorida (HCl) dan larutan amonium khlorida (NH4Cl), dilanjutkan dengan proses kalsinasi. Hasil penelitian menunjukkan bahwa aktifasi zeolit alam dapat meningkatkan rasio Si/Al dan luas permukaan. Semua adsorben yang diuji mempunyai kemampuan mengadsorpsi karbon monoksida. Berdasarkan model adsorpsi Langmuir yang diperoleh, karbon aktif dan zeolit alam mempunyai kapasitas adsorpsi yang paling besar. Dengan menggunakan kondisi tekanan 1 atmosfir, kapasitas adsorpsi adalah 0,0682 mmol/g untuk karbon aktif, 0,0464 mmol/g untuk zeolit alam teraktifasi dengan ukuran partikel 400 nm dan 0,0265 mmol/g untuk zeolit alam teraktifasi dengan ukuran partikel (37-50) μm.

PEMBUATAN KARBON AKTIF DARI BATU BARA TERMODIFIKASI TIO2 UNTUK PENYERAP KARBON MONOKSIDA

Prosiding Semnastek PROSIDING SEMNASTEK 2015
Publisher : Universitas Muhammadiyah Jakarta

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Abstract

Peristiwa kebakaran dapat menyebabkan kematian karena terpapar CO dari asap kebakaran. Oleh karena itu kandungan CO pada asap kebakaran bisa diadsorpsi menggunakan adsorben seperti karbon aktif. Penelitian ini bertujuan untuk membuat karbon aktif dari batu bara menggunakan aktive agent kalium hidroksida (KOH) dan aktifasi fisika pada suhu tinggi. Karbon aktif yang dihasilkan digunakan untuk menyerap Carbon monoksida (CO).  Adapun tahapan batu bara dicampurkan dengan larutan KOH selama 1 jam pada suhu 200oC, kemudian campuran diaktifasi fisika pada suhu 800oC selama 2 jam. Hasil penelitian menunjukkan bahwa proses aktifasi dapat menghasilkan karbon aktif dengan luas permukaan 932 m2/gr, dengan rendemen 40,4%. Hasil karakterisasi X–Ray Fluorescence menunjukkan bahwa proses aktifasi dalam pembuatan karbon aktif dapat mengurangi kandungan pengotor seperti oksida logam  yang terdapat dalam batu bara. Dari uji kemampuan penyerapan karbon aktif terhadap karbon monoksida menunjukkan bahwa semakin kecil ukuran partikel semakin meningkat kemampuan karbon aktif menyerap karbon monoksida. Semakin banyak massa karbon aktif yang didispersikan semakin meningkat jumlah karbon monoksida yang terserap. Karbon aktif dengan ukuran partikel 74 μm dan massa 3 gr mampu menyerap karbon monoksida sebesar 5,75%. Penambahan TiO2 pada karbon aktif dapat meningkatkan penyerapan terhadap karbon monoksida, hasil terbaik diperoleh karbon aktif yang termodifikasi logam TiO2 dengan persentase penyerapan karbon monoksida sebesar 6,81%

Effects of Ph on Calcium Carbonate Precipitation Under Magnetic Field

Makara Journal of Technology Vol 13, No 2 (2009)
Publisher : Directorate of Research and Community Services, Universitas Indonesia

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Abstract

Magnetic field effect on CaCO3 precipitation is the key parameter in evaluating the effectiveness of Anti-scale Magnetic Treatment (AMT). The purpose of this study was to investigate magnetic fields influence on CaCO3 precipitation in high and low super-saturated CaCO3 solution by varied pH CaCO3 solution using circulation flow fluid system. The observation results in the high super saturated solution (pH 8.5) showed the increase of precipited CaCO3 in magnetized solutions compared to those in non-magnetic solution during circulation process. In the low super-saturated CaCO3 solution (pH 6.4) it was found that magnetic treatment increased CaCO3 precipitation after circulation process. In high super-saturated solution, magnetic field strengthens ion interactions, which reduce precipitation during circulation process. However, in low super-saturated CaCO3 solution, magnetic field weakens hydrate ion interaction which indicated by decreasing of the conductivity of solution. It increases the precipitation of CaCO3 after the circulation of magnetization process has completed.

Kinetic Model For Triglyceride Hydrolysis Using Lipase:Review

Makara Journal of Technology Vol 11, No 1 (2007)
Publisher : Directorate of Research and Community Services, Universitas Indonesia

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Abstract

Triglyceride hydrolysis using lipase has been proposed as a novel method to produce raw materials in food and cosmetic industries such as diacylglycerol, monoacylglycerol, glycerol and fatty acid. In order to design a reactor for utilizing this reaction on industrial scale, constructing a kinetic model is important. Since the substrates are oil and water, the hydrolysis takes place at oil-water interface. Furthermore, the triglyceride has three ester bonds, so that the hydrolysis stepwise proceeds. Thus, the reaction mechanism is very complicated. The difference between the interfacial and bulk concentrations of the enzyme, substrates and products, and the interfacial enzymatic reaction mechanism should be considered in the model.

Performance of Hollow Fiber Membrane Gas-Liquid Contactors to Absorb CO2 Using Diethanolamine (Dea) as a Solvent

Makara Journal of Technology Vol 13, No 2 (2009)
Publisher : Directorate of Research and Community Services, Universitas Indonesia

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Abstract

This study uses DEA solution to absorb CO2 from the gas flow through the hollow fiber membrane contactors. This study aims to evaluate the performance of hollow fiber membrane contactors to absorb CO2 gas using DEA solution as solvent through mass transfer and hydrodynamics studies. The use of DEA solution is to reduce the mass transfer resistance in the liquid phase, and on the other side, the large contact area of the membrane surface can cover the disadvantage of membrane contactors; additional mass transfer resistance in the membrane phase. During experiments, CO2 feed flows through the fiber lumens, while the 0.01 M DEA solution flows in the shell side of membrane contactors. Experimental results show that the mass transfer coefficients and fluxes of CO2 increase with an increase in both water and DEA solution flow rates. Increasing the amount of fibers in the contactors will decrease the mass transfer and fluxes at the same DEA solution flow rate. Mass transfer coefficients and CO2 fluxes using DEA solution can achieve 28,000 and 7.6 million times greater than using water as solvent, respectively. Hydrodynamics studies show that the liquid pressure drops in the contactors increase with increasing liquid flow rate and number of fibers in the contactors. The friction between water and the fibers in the contactor was more pronounced at lower velocities, and therefore, the value of the friction factor is also higher at lower velocities.

CO2 Absorption from Its Mixture with CH4 or N2 through Hollow Fiber Membrane Contactor using Water as Solvent

Makara Journal of Technology Vol 11, No 2 (2007)
Publisher : Directorate of Research and Community Services, Universitas Indonesia

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Abstract

Hollow fiber membrane contactors have been widely used as gas-liquid contactors recently such as in the CO2 absorption process from gas stream. This research aims to evaluate the effectiveness of hollow fiber membrane contactor to absorb CO2 from its mixture with CH4 or N2 using water through mass transfer and hydrodynamic tests. There are 3 membrane modules used in this research with shell diameter of 1.9 cm, length of 40 cm, outer fiber diameter of 2.7 mm and fiber number in the contactors of 10, 15 and 20. Liquid flow rates in the hollow fiber membrane contactors are varied in this research. Research results show that mass transfer coefficients in the membrane contactor increase with increasing liquid flow rate and decrease with increasing fiber number in the contactor. Flux of CO2 into water can achieve 1.4x10-9 mol CO2 /m2.s and mass transfer coefficients can achieve 1.23 x 10-7 m/s. Meanwhile, hydrodynamic test results show that water pressure drop in the membrane contactors increase with increasing fibernumber in the contactors.

Aktivasi Zeolit Alam Lampung sebagai Adsorben Karbon Monoksida Asap Kebakaran

Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2016: Prosiding SNTKK 2016
Publisher : Prosiding Seminar Nasional Teknik Kimia "Kejuangan"

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Abstract

This study aims to absorb the carbon monoxide (CO) gas using Lampung natural zeolite as an adsorbent. Natural Zeolite has porous crystal structure, large surface area, high thermal stability, non-toxic, and effective. Natural zeolites contain many impurities, then it must be activated. Activation of natural zeolite was done by soaking in a solution of 2% HF for 10 minutes with stirring. Furthermore, dealumination natural zeolite carried out  by soaking in a solution of 6 M HCl for 30 minutes. Zeolite was soaked with a solution of 0.1 M NH4Cl and then was calcined.  Then Activated Natural zeolite was tested the adsorption of cabon monoxide gas from burning tissue paper. Variations in particle size of the zeolite is 53-106 μm, 106-150 μm and 150-212 μm. The results showed that activated natural zeolite with a particle size of 53-106 microns can adsorb CO gas at 379 ppm (12.2%) of the initial concentration for 20 minutes.

Pengambilan Kembali Logam Litium dan Cobalt dari Baterai Li-Ion dengan Metode Leaching Asam Sitrat

Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2016: Prosiding SNTKK 2016
Publisher : Prosiding Seminar Nasional Teknik Kimia "Kejuangan"

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Abstract

Batteries are often used in mobile phones is a type of battery Li-Ion or Lithium Ion Battery (LIB). Cobalt and lithium used in batteries is important metal that is often used in various fields. Batteries that are not used become hazardous waste. Metal recovery from waste batteries is one solution to maintain the availability of raw materials of lithium and cobalt. In this study the recovery of lithium and cobalt was done with leaching method, which dissolves metals from the waste battery into the leaching agent. Citric Acid (C6H8O7) was used as the leaching agent, because it is one of the organic acids that can be used in the leaching process lithium. The results showed that the metal content in batteries LIB 35.30 ppm lithium metal and 408.55 ppm cobalt metal. The concentration of leaching agent take effect on the percentage of leaching. The optimum operating conditions for the leaching process is at a concentration of citric acid of 1.5 M; with a contact time of 30 minutes and a temperature of 55 ° C.  In these conditions, the optimum percentage was obtained for the leaching of metal lithium and cobalt are 98.08% and 86.28%, respectively, respectively.

ANALISIS FAKTOR-FAKTOR MOTIVASI KERJA PEGAWAI PADA RUMAH SAKIT UMUM DAERAH PROF DR. H.M.CHATIBQUZWAIN KABUPATEN SAROLANGUN

Jurnal Manajemen Terapan dan Keuangan Vol 7 No 03 (2018): Jurnal Manajemen terapan dan keuangan Volume 07 No. 03 SEPTEMBER - DESEMBER 20
Publisher : Jurnal Manajemen Terapan dan Keuangan

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Abstract

ABSTRAK   Penelitian ini bertujuan untuk memperoleh gambaran faktor-faktor motivasi kerja pegawai Rumah Sakit Umum Daerah dan untuk menganalisis foktor-faktor motivasi kerja pegawai Rumah Sakit Umum Daerah Prof Dr. H.M.Chatib QuzwainKabupaten Sarolangun.Metode penelitian yang akandigunakan adalah penelitian survey. Kegiatan yang dilakukan adalah meneliti dengan menggunakan kuesioner sebagai alat untuk mengumpulkan data. Metode yang digunakan adalah Deskriptif Kualitatif.Teknik analisis data dengan menggunakan skor rata-rata.Hasil penelitian menunjukkan bahwa motivasi pegawaiRSUD Prof Dr. H.M.Chatib Quzwain Kabupaten Sarolangun secara keseluruhan memperoleh kategori termotivasi. Faktor motivasi berupa kebutuhan sosial mendapatkan penilaian tertinggi dari pegawai dibandingkan dengan penilaian terhadap pemenuhan faktor motivasi lainnya. Skor yang terendah yang diperoleh dari hasil perhitungan adalah faktor aktualisasi diri dengan kategori kurang termotivasi.   Kata Kunci : motivasi, kerja, pegawai   

PENGARUH KETEPATAN SKEDUL ANGGARAN DAN KARAKTERISTIK TUJUAN ANGGARAN TERHADAP KINERJA MANAJERIAL SATUAN KERJA PERANGKAT DAERAH KABUPATEN BATANGHARI PROVINSI JAMBI

Jurnal Akuntansi & Keuangan Unja Vol 2 No 3 (2017): Jurnal Akuntansi & Keuangan Magister Ilmu Akuntansi Universitas Jambi
Publisher : Magister Ilmu Akuntansi Universitas Jambi

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Abstract

Penelitian tentang penganggaran, pengaruh ketepatan skedul, dan partisipasi penyusun anggaran telah banyak dilakukan, tetapi pengaruh ketepatan skedul anggaran dan karakteristik tujuan anggaran terhadap kinerja manajerial SKPD sepanjang pengetahuan saya belum pernah di lakukan. Tujuan penelitian ini di lakukan untuk mencari bukti empiris apakah ada pengaruh ketepatan skedul anggaran dan karakteristik tujuan anggaran terhadap kinerja manajerial SKPD pada Pemerintah Kabupaten Batanghari. Populasi penelitian ini adalah seluruh SKPD yang ada di lingkungan Pemerintah Kabupaten Batanghari. Unit analisisnya adalah unsur pimpinan dan penyusun anggaran. Pengumpulan data dengan kuesioner yang di antar langsung oleh penulis, sebelum dilakukan pengujian hipotesis dengan analisa regresi berganda, terlebih dahulu dilakukan pengujian kualitas data dan uji asumsi klasik. Hasil penelitian menunjukkan bahwa secara simultan dan secara parsial ketepatan skedul anggaran dan karakteristik tujuan anggaran berpengaruh secara signifikan terhadap kinerja manjerial SKPD. Kata Kunci:   Ketepatan skedul anggaran, karakteristik tujuan anggaran dan kinerja manajerial SKPD.