Articles

Found 14 Documents
Search

PENGARUH SUHU PADA HYDROCRACKING OLI BEKAS MENGGUNAKAN KATALIS Cr/ZAA Dewi, Tri Kurnia; Mediana, Meta; Hidayati, Nopektaria
Jurnal Teknik Kimia Vol 20, No 2 (2014): Jurnal Teknik Kimia
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Sriwijaya

Show Abstract | Original Source | Check in Google Scholar | Full PDF (362.295 KB)

Abstract

Jumlah kendaraan di Indonesia terus bertambah dari tahun ke tahun. Hal ini mengakibatkan oli bekas menjadi semakin banyak, yang berpotensi mencemari lingkungan. Oleh karena itu, diperlukan cara untuk mengubah oli bekas menjadi sesuatu yang lebih berguna. Salah satunya adalah membuat bahan bakar cair dari oli bekas. Di dalam oli bekas terdapat rantai karbon yang dapat diubah menjadi hidrokarbon rantai pendek melalui proses hydrocracking menggunakan katalis Cr/ZAA. Proses hydrocracking dilakukan dengan suhu sebagai variabel bebas yaitu 300oC, 350oC, 400oC, 450oC dan 500oC. Variabel tetap yang digunakan adalah volume umpan 40 ml, berat katalis 1 gr, dan laju alir gas hidrogen 20 ml/det. Produk hydrocracking yang dihasilkan diukur kecepatan pembentukan produk dan berat jenisnya, serta dianalisa persen fraksi bensin, kerosin, dan solar. Hasil penelitian menunjukkan bahwa kecepatan produksi dan persen fraksi bensin meningkat dengan semakin tingginya suhu, sedangkan persen fraksi kerosin dan solar semakin rendah, dan nilai berat jenisnya tetap, tidak dipengaruhi oleh suhu. Kata kunci : Oli bekas, bahan bakar cair, hydrocracking, katalis, Cr/ZAA.   
PENGARUH WAKTU PERENDAMAN, PENAMBAHAN SERAT DAN SUHU PEREBUSAN TERHADAP KUALITAS KERTAS HASIL DAUR ULANG KERTAS BEKAS Dewi, Tri Kurnia; Wirson, Putra Wijaya; Simaremare, Charles DW
Jurnal Teknik Kimia Vol 17, No 5 (2011): Jurnal Teknik Kimia
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Sriwijaya

Show Abstract | Original Source | Check in Google Scholar | Full PDF (405.613 KB)

Abstract

Telah dilakukan penelitian pembuatan kertas berbahan baku kertas bekas dengan proses daur ulang. Daur ulang kertas bekas dapat digunakan sebagai solusi pemanfaatan kertas bekas agar dapat mengurangi dampak buruknya terhadap lingkungan. Penelitian ini mengamati pengaruh waktu perendaman, penambahan serat, dan suhu perebusan  terhadap kualitas kertas yang dihasilkan. Jangkauan variabel yang digunakan pada penelitian ini adalah waktu perendaman 8 ,10 ,12 ,14 ,16, 18, dan 20 jam, Penambahan serat dan suhu perebusan 60 ,80 dan 100oC. Hasil kualitas kertas  dianalisa secara gravimetri untuk mendapatkan % ISO Brightness dan Viskositas. Peningkatan waktu perendaman  tidak begitu berpengaruh terhadap % ISO brightness, tetapi berpengaruh terhadap viskositas. Peningkatan suhu perebusan berpengaruh terhadap % ISO brightness dan viskositas. Diperoleh hasil kertas terbaik pada waktu perendaman 20 jam, tidak menggunakan penambahan serat, dan suhu perebusan 100oC.
Preparation And Characterization Of Cr/Activated Carbon Catalyst From Palm Empty Fruit Bunch Fanani, Zainal; Rohendi, Dedi; Dewi, Tri Kurnia; Dzulfikar A, Muhammad
Indonesian Journal of Fundamental and Applied Chemistry Vol 1, No 2 (2016): June 2016
Publisher : Indonesian Journal of Fundamental and Applied Chemistry

Show Abstract | Original Source | Check in Google Scholar | Full PDF (333.473 KB)

Abstract

Preparation and characterization of Cr/activated carbon catalyst from palm empty fruit bunch had been done. The research were to determine the effect of carbonization temperature towards adsorption of ammonia, iodine number, metilen blue number, and porosity of activated carbon and Cr/activated carbon catalyst. The determination of porosity include surface area, micropore volume and total pore volume. The results showed the best carbonization temperature activated carbon and Cr/activated carbon catalyst at 700°C. The adsorption ammonia of activated carbon and Cr/activated carbon catalyst as 6.379 mmol/g and 8.1624 mmol/g. The iodine number of activated carbon and Cr/activated carbon catalyst as 1520.16 mg/g and 1535.67 mg/g. The metilen blue number of activated carbon and Cr/activated carbon catalyst as 281.71 mg/g and 319.18 mg/g. The surface area of activated carbon and Cr/activated carbon catalyst as 1527.80 m2/g and 1652.58 m2/g. The micropore volume of activated carbon and Cr/activated carbon catalyst as 0.7460 cm3/g and 0.8670 cm3/g. The total pore volume of activated carbon and Cr/activated carbon catalyst as 0.8243 cm3/g and 0.8970 cm3/g.Keywords : activated carbon, palm empty fruit bunch, porosity, catalyst, chromium
Conversion of Waste Oil into Fuel Oil : Dewi, Tri Kurnia
Sriwijaya International Seminar on Energy-Environmental Science and Technology Vol 1, No 1 (2014)
Publisher : Sriwijaya International Seminar on Energy-Environmental Science and Technology

Show Abstract | Original Source | Check in Google Scholar | Full PDF (118.786 KB)

Abstract

Research has been conducted to convert waste lubrication oil into fuel oil. This work is the second part of a bigger work entittled “Conversion of Waste Oil into Fuel Oil”. The first part dealing with the production of catalyst and the effect of temperature, whilst this part studying the effect of catalyst ratio. This work was done with procedure similar with the first part of the work. Convertion of waste lubrication oil into fuel oil was done using hydrocracking process with catalyst of combination of chromium and activated natural zeolith (Cr/ZAA). Controlled variables used for this researh were the type of waste oil (lubrication oil), feed volume (40 ml), temperature (500°C), and hydrogen gas rate (20 ml/sec). The weight ratio of the catalyst and waste oil feed was varied at 1/8, 1/4, 1/3, 1/2, and 2/3. The parameters used to analyse the results were the amount of hydrocracking product, percentage of cracking fraction (gasoline, kerosene and solar) in the product and the heating value of the product. Analytic works were carried out with GC for cracking fraction and bomb calorimeter for heating value of the produced fuel oil. Results showed that the amount of hydrocracking product decreases with the increase of catalyst ratio. Increasing catalyst ratio increases gasoline fraction lineary, decreases kerosene and solar fractions. The heating value of the product lineary increases with catalyst ratio. Best catalyst ratio for this work was 1/8 to get maximum amount of product (13.16 ml for 40 ml feed), and 2/3 to get maximum gasoline fraction (56.70%), and highest heating value (44.92 kJ/gr).
Peningkatan Keterampilan Pemecahan Masalah Pengukuran Sudut melalui Penerapan Model Pembelajaran Problem Solving Learning (PSL) pada Peserta Didik Kelas IV Sekolah Dasar Dewi, Tri Kurnia
Jurnal Didaktika Dwija Indria Vol 7, No 3 (2019): Jurnal Didaktia Dwija Indria Maret 2019
Publisher : Universitas Sebelas Maret

Show Abstract | Original Source | Check in Google Scholar

Abstract

The direction of this research was to upgrade the problem solving skills of angular measurement by applying the problem solving learning (PSL) model in fourth grade students of public elementary school Tambakreja 02 Cilacap 2018/2019 academic year. This research was a classroom action research consists of 3 cycles with of 2 meetings. Every cycle consist 4 phases. The subjects of this research were 27 students and teachers.Data accumulating technique used interviews, observation, tests, and documentation. The data validity technique used source triangulation and technical triangulation. Data analysis technique maked use of critical analysis, descriptive comparative techniques, and interactive analysis models. The results showed that the average score of pre-action was 41.04 with classical completeness of 3.70%, increase in first cycle to 65,85 with classical completeness of 33,33%, increased at second cycle to 77,36 with classical completeness 66.67%, increased again in third cycle to 83,41 with classical completeness of 88.89%. Results of the research, it can be summarized that through the application of the problem solving learning (PSL) model can improve the problem solving skills of angular measurements in fourth grade student of SDN Tambakreja 02 Cilacap 2018/2019 academic year.Keyword: problem solving skills, problem solving learning model, angular measurement, and elementary school
Synthesis of Catalyst Cobalt Impregnated on Activated Natural Zeolite, Co/ANZ Dewi, Tri Kurnia; Fanani, Zainal
Indonesian Journal of Fundamental and Applied Chemistry Vol 2, No 1 (2017): February 2017
Publisher : Indonesian Journal of Fundamental and Applied Chemistry

Show Abstract | Original Source | Check in Google Scholar | Full PDF (456.046 KB)

Abstract

Research has been done on the synthesis of catalyst Co/Activated Natural Zeolite. The variables studied were the mass ratio of Cobalt to Zeolite and temperature of reduction during catalyst activation. The catalyst produced were analysed in their acidity and surface area. Acidity was presented in the form of ammonia and pyridine adsorption on the catalyst surface. The results showed the increasing Cobalt to Zeolite mass ratio will increase acidity of the catalyst produced. Reduction temperature during catalyst activation also gave same effect as Cobalt to Zeolite mass ratio did. Best ratio within the range of this study was Cobalt to Zeolite mass ratio of 6:20, which was found at reduction temperature of 400 C. This ratio gave catalyst acidity correspond to ammonia adsorption of 6.4615 mmol/g, and to pyridine adsorption of 2.6047 mmol/g catalyst. The best reduction temperature was 450 C at ratio of 6:20. The acidity of this catalyst was of 7.5202 mmol/g as in ammonia adsorption, and was of  3.662 mmol/g as in pyridine adsorption. Catalyst surface area of the best ratio was 32.63 m2/g, whilst catalyst surface area of the best reduction temperature was 38.95 m2/g. Keywords: catalyst, cobalt, activated natural Zeolite 
PENGARUH RASIO REAKTAN PADA IMPREGNASI DAN SUHU REDUKSI TERHADAP KARAKTER KATALIS KOBALT/ZEOLIT ALAM AKTIF Dewi, Tri Kurnia; Mahdi, Mahdi; Novriyansyah, Teguh
Jurnal Teknik Kimia Vol 22, No 3 (2016): Jurnal Teknik Kimia
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Sriwijaya

Show Abstract | Original Source | Check in Google Scholar | Full PDF (551.927 KB)

Abstract

Pada proses reaksi kimia seperti hidrogenasi, cracking maupun hydrocracking, dibutuhkan katalis perengkah yang merupakan katalis heterogen. Salah satu jenis katalis heterogen adalah katalis logam-pengemban, yang terdiri dari logam yang diembankan pada bahan pengemban padat seperti zeolit alam aktif. Pada penelitian ini, dilakukan pengembanan katalis logam kobalt ke dalam zeolit alam aktif melalui metode impregnasi. Variabel yang diteliti pada penelitian ini adalah rasio berat reaktan (Co dan zeolit alam aktif) pada impregnasi katalis dengan variasi 2:20; 3:20; 4:20; 5:20 dan 6:20 serta suhu reduksi dengan variasi 250oC; 300oC; 350oC; 400oC dan 450oC. Produk katalis Co/ZAA dianalisa tingkat keasamannya dengan cara adsorpsi amoniadan piridin. Luas permukaan katalis Co/ZAA dianalisa menggunakan Surface Area Analyzer dengan metode BET. Hasil penelitian menunjukkan bahwa semakin besar rasio berat reaktan kobalt/zeolit alam aktif maka semakin besar pula keasaman dan luas permukaan katalis yang terbentuk. Keasaman dan luas permukaan katalis Co/ZAA juga mengalami kenaikan seiring dengan kenaikan suhu reduksi. Keasaman katalis terbesar pada penelitian ini adalah pada rasio reaktan Co/ZAA 6:20 dan pada suhu reduksi 450 oC yaitu masing-masing 6,4615 mol/g dan 7,5202 mol/g (keasaman dengan adsorbat amonia), 2,6047 mol/g dan 3,6662 mol/g (keasaman dengan adsorbat piridin). Luas permukaan katalis terbesar pada penelitian ini adalah pada rasio berat reaktan Co/ZAA 6:20 yaitu 32,63 m2/g dan pada suhu reduksi 450 oC yaitu 38,95 m2/g. Kata kunci: impregnasi, katalis Co/ZAA, keasaman
PEMBUATAN KARBON AKTIF DARI KULI UBI KAYU (Mannihot esculenta) Dewi, Tri Kurnia; Nurrahman, Arif; Permana, Edwin
Jurnal Teknik Kimia Vol 16, No 1 (2009): Jurnal Teknik Kimia
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Sriwijaya

Show Abstract | Original Source | Check in Google Scholar | Full PDF (62.938 KB)

Abstract

Some research proved that activated carbon could be made from organic materials or anorganic material with very high carbon content. The exist research of activated carbon  from coconut shell, bagasse, and saw dust. In fact, there’s a lot of material can be used as raw material, like cassava skin. At this research, done with activator type variable ( HCL, NAOH, and CaCl2), activation period   ( 24 hours, 22 hours, 20 hours and 18 hours ), and particle size (- 115 mesh, - 60+115 mesh, - 32+60 mesh, and - 16+32 mesh). This research analyzed is volatile matter, water content, and iodium adsorption. The best activator at making of this activated carbon is HCl. The best activation period is 24 hours and the best particle size is - 115 mesh,  In industrial process, activated carbon is used for deodorized, adsorbs taste, eliminate colours and organic contaminant. Testing for active carbon in this research was based on activated carbon quality standard  from Standar Industri Indonesia  No. 0258-88.
PENGARUH TEMPERATUR, WAKTU PEMASAKAN DAN KONSENTRASI ASAM ASETAT PADA PROSES PEMBUATAN PULP DARI ECENG GONDOK Dewi, Tri Kurnia; Farera, Vina
Jurnal Teknik Kimia Vol 17, No 7 (2011): Jurnal Teknik Kimia
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Sriwijaya

Show Abstract | Original Source | Check in Google Scholar | Full PDF (336.359 KB)

Abstract

Telah dilakukan penelitian pembuatan pulp dari bahan baku eceng gondok dengan proses organosolv (acetocell) menggunakan larutan pemasak asam asetat dan katalis HCl. Tingginya kadar selulosa menunjukkan potensi eceng gondok baik untuk dijadikan bahan baku pembuatan pulp. Penelitian ini mengamati pengaruh temperatur pemasakan, waktu pemasakan dan konsentrasi asam asetat, terhadap pulp yang dihasilkan. Variabel yang digunakan pada penelitian ini adalah temperatur pemasakan 50 oC, 70 oC, 80 oC, 90 oC dan 100 oC, waktu pemasakan 30 menit, 60 menit, 90 menit dan 120 menit dan konsentrasi asam asetat 20 %, 40 %, 50 %, 60 % dan 70 %. Hasil pulp dianalisa untuk mengetahui kadar selulosa dan kadar lignin dalam pulp. Pada penelitian ini diperoleh hasil pulp terbaik pada temperatur 80 oC, waktu memasakan 1 jam dan konsentrasi asam asetat 50 %, dengan kadar selulosa 61,67% dan kadar lignin 6,11%.
PENGARUH PERLAKUAN BAHAN BAKU, JENIS MIKROBA, JUMLAH MIKROBA RELATIF, RASIO AIR TERHADAP BAHAN BAKU, DAN WAKTU FERMENTASI PADA FERMENTASI BIOGAS Dewi, Tri Kurnia; Amalia, Vikha Rianti; Agustin, Dini Rohmawati
Jurnal Teknik Kimia Vol 17, No 7 (2011): Jurnal Teknik Kimia
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Sriwijaya

Show Abstract | Original Source | Check in Google Scholar | Full PDF (119.86 KB)

Abstract

Kandungan di dalam kulit pisang berpotensi sebagai sumber energi terbarukan, seperti biogas. Penelitian ini menggunakan proses fermentasi. Kulit pisang yang diberi perlakuan difermentasikan selama 5 hari untuk mendapatkan hasil yang terbaik. Setelah mendapatkan hasil terbaik, kulitt pisang yang diberi perlakuan, kemudian ditambahkan mikroba dan difermentasikan. Hasil yang paling banyak divariasikan jumlah mikrobanya. Jumlah mikroba yang menghasilkan banyak kadar metannya lalu ditambahkan air sesuai ketentuan. Hasil penelitian menunjukkan bahwa kadar metan yang dihasilkan akan mencapai optimum pada waktu fermentasi tertentu (waktu optimum). Kadar metan tertinggi didapat pada kondisi bahan baku diblender, menggunakan mikroba Methanobacterium Sp., jumlah mikroba relative sebanyak 500 gram, air yang digunakan sebanyak 5 liter, dan waktu fermentasi selama 15 hari yaitu sebesar 2,234 %.