Jurnal Teknik Kimia Indonesia最新文献

{"title":"Penghematan konsumsi katalis dalam proses hidrolisis tandan kosong sawit untuk produksi furfural","authors":"Diyah Fadjarwaty, H. Susanto","doi":"10.5614/jtki.2005.4.3.3","DOIUrl":"https://doi.org/10.5614/jtki.2005.4.3.3","url":null,"abstract":"One of possible utilizations of abundant agricultural solid waste such as palm oil empty fruit bunches is the conversion furfural via acid hydrolysis and followed by azeotrope distillation. With the aim to reduce the consumption of H2SO4 in the furfural production from oil palm empty fruit bunches, acid hydrolysis was accomplished using the spent acid left as the bottom product of distillation during furfural recovery. The use of spent acid could reduce the need of H2SO4 from 42 at the first cycle to 17 mL/kg at the second cycle, while the need of H2SO4 in the third cycle was 29 mL/kg. Furfural yields in these cycles were up to 16.8, 16.1 and 10.7 g/kg respectively. The use of spent acid at the fourth cycle was not effective anymore. Keywords: Oil Palm Empty Fruit Bunches, Furfural, Acid Hydrolysis AbstrakSalah satu pemanfaatan biomassa limbah padat pertanian dan perkebunan adalah produksi furfural melalui proses hidrolisis dan distilasi azeotrop. Hidrolisis TKS (tandan kosong sawit) dilaksanakan dalam suasana asam yang umumnya dengan H2SO4 sebagai katalis. Pada operasi distilasi pengambilan furfural, H2SO4 bekas hidrolisis tertinggal bersama air sebagai produk bawah. Untuk mengurangi konsumsi H2SO4 dalam hidrolisis, produk bawah distilasi ini terbukti dapat digunakan sebagai cairan hidrolisis berulang sampai 3 kali. Pada hidrolisis dengan cairan segar, kebutuhan H2SO4 (98% teknis) adalah 42 mL/kg bahan baku. Tetapi pada hidrolisis dengan produk bawah ulangan pertama, kebutuhan H2SO4 tambahan untuk menyesuaikan pH cairan pemasak hanya 17 mL/kg TKS kering. Pada hidrolisis dengan produk bawah ulangan kedua, kebutuhan H2SO4 29 mL/kg. Perolehan furfural dari ketiga ulangan hidrolisis berturut-turut adalah 16,8; 16,1 dan 10,7 g/kg. Penggunaan produk bawah distilasi untuk hidrolisis ulangan keempat memberi hasil yang kurang memuaskan.Kata Kunci: TKS, Furfural, Hidrolisis Asam","PeriodicalId":138501,"journal":{"name":"Jurnal Teknik Kimia Indonesia","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133405669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pengaruh perbandingan nutrisi terhadap pengolahan minyak secara biologis dengan bakteri mixed-culture","authors":"Tri Widjaja, Lindu Sunarko","doi":"10.5614/jtki.2008.7.1.7","DOIUrl":"https://doi.org/10.5614/jtki.2008.7.1.7","url":null,"abstract":"The physical crude oil waste treatment still leaves dissolved organic.  The process must be continued by biological waste treatment.   The oil waste treatment was investigated by biological process: batch and continuous. It used mixed bacterial culture that was isolated from biological crude oil waste preparation. The influence of composition nutrient C:N:P was research using nutrient composition  100:10:1, 100:5:1  and  100:1:1  for batch and continuous experiment. Batch experiment is using initial COD concentration inlet (864, 691, 410 and 225 ppm), bacterial concentration (10%, 20% and 30% as b/v) beside nutrient composition influences. Continuous experiment is using influent flow rate 36 l h-1, influent COD contents 300 mg l-1, dissolved oxygen in aeration tank condition is maintained 2 mg l-1. Suspended solid (SS) concentration is maintained 1000 mg l-1 and sludge age 15 days. The batch research showed that maximum decreasing of COD was happened in initial COD 691 ppm, microbial concentration 10% (b/v) or 0,05 gr/500 ml solution with nutrient composition 100:10:1 elimination ability 83,8% and decreasing maximum oil contents 81,8%. The microbial identification result are obtained that main microorganism are Pseudomonas, Micrococcus and Vibrio. The continuous research obtained that maximum elimination COD values  70% at composition nutrient  100: 10:1. Keywords: mixed-culture bacterial, aeration tank AbstrakPengolahan secara fisik limbah minyak mentah masih menyisakan organik terlarut. Untuk itu perlu dilanjutkan dengan pengolahan limbah secara biologis. Penelitian pengolahan limbah minyak telah dilakukan secara biologis baik dengan batch maupun kontinyu. Digunakan bakteri kultur campuran yang telah diisolasi dari berbagai tempat pengolahan limbah biologis minyak mentah. Pengaruh nutrisi C:N:P telah dilakukan variasi dengan perbandingan 100:10:1, 100:5:1 dan 100:1:1 baik untuk percobaan batch maupun kontinyu. Percobaan secara batch dilakukan dengan variabel adalah konsentrasi COD awal yang masuk (864, 691, 410 dan 225 ppm), konsentrasi bakteri (10%, 20% dan 30% sebagai b/v) disamping pengaruh perbandingan nutrisi. Sedangkan percobaan secara kontinyu dilakukan menggunakan laju alir influent 36 l h-1, kandungan COD influent 300 mg l-1 , kondisi tangki aerasi kondisi oksigen terlarut dijaga minimum 2 mg l-1, konsentrasi padatan  tersuspensi (SS) dipertahankan 1000 mg l-1 dan umur lumpur 15 hari. Hasil penelitian batch menunjukkan bahwa pada COD awal 69I ppm, konsentrasi mikroba 10% (b/v) atau 0,05 gr/500 ml larutan dengan nutrisi 100:10:1 terjadi penurunan COD tertinggi dengan kemampuan penyisihan sebesar 83,8% serta mampu  menurunkan kandungan minyak tertinggi sebesar 81,8%. Hasil identifikasi bakteri didapatkan mikroba yang berperan adalah Pseudomonas, Micrococcus dan Vibrio. Sedangkan untuk percobaan kontinyu diperoleh hasil bahwa penyisihan COD tertinggi dihasilkan pada perbandingan nutrisi C:N:P = 100:10:1 sebesar 70%. Kata Kunci: bakteri ku","PeriodicalId":138501,"journal":{"name":"Jurnal Teknik Kimia Indonesia","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130419923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kopolimerisasi pencangkokan asam akrilat pada film pp dengan teknik iradiasi awal","authors":"Yohan Yohan, Rifai Nur, Lilik Hendrajaya, E. S. Siradj","doi":"10.5614/jtki.2005.4.3.7","DOIUrl":"https://doi.org/10.5614/jtki.2005.4.3.7","url":null,"abstract":"Grafting pre-irradiation process of acrylic acid monomer on polypropylene (PP)film for hydrophilic membrane as cationic exchanger membrane have been done. PP film is irradiated by -ray and is then grafted by acrylic acid monomer in wate1: The preparation conditions such as rate and total dose of irradiation, monomer concentration, time and temperature of grafting have been studied in order to get the optimum grafting process. Some properties of the prepared grafted membranes were characterized and accordingly the possibility of its applications in fuel cell and in waste water treatment for toxic heavy metals removals, such as As, Cd, Co, Cu, Fe and Pb was investigated. The optimum grafting condition was as follows: total dose was 45 kGy, dose rate was 7 kGy/hour, acrylic acid was 40% volume, grafting time was 90 minutes, and grafting temperature was 70oC which gave a percent of grafting PP-g-AA of 350-450% weight. The chelated metal ions were easily desorbed by treating the membrane with 0.I N HCI for 2 hours at room temperature. The sorption level of grqfted membrane (PP-g-AA) to metallic ions are Fe> Co> Cu >As> Cd > Pb. Finally, a mixture of three metals in the same feed solution was used to determine the selectivity of the membrane toward different metals. The results obtained for the prepared membranes showed a promise for their applicability in the removal of heavy metals from wastewate1:Keywords: Grafted Pre-irradiation,Cathionic  Exchanger Membrane, Fuel Cell, Waste TreatmentAbstrakTelah dilakukan proses pencangkokan dengan teknik iradiasi awal monomer asam akrilat padafilm polipropilena (PP) untuk bahan membran hidrofil yang dapat berperan sebagai membran penukar kation. Film PP diiradiasi dengan sinar-y dan selanjutnya dicangkok menggunakan monomer asam akrilat dalam pelarut air. Beberapa kondisi preparasi ditentukan untuk mendapatkan persen pencangkokan yang optimum, seperti laju dan dosis total radiasi, konsentrasi monomer, waktu dan suhu pencangkokan. Karakterisasi dari beberapa sifat bahan membran tercangkok juga dipelajari dan dilakukan pengujian kemungkinan penggunaannya   dalam fuel cell dan dalam pengolahan limbah yang mengandung logam berat beracun, seperti As, Cd, Co, Cu, Fe, dan Pb. Dari hasil penelitian diperoleh kondisi relatif baik untuk pencangkokan yaitu dosis total 45 kGy, laju dosis 7 kGy/jam, asam akrilat 40% volume, waktu pencangkokan 90 menit, dan suhu pencangkokan 70oC memberikan persen pencangkokan PP-g-AA = 350-450% berat. Ion-ion logam yang mudah membentuk senyawa kelat relatif lebih mudah dielusi dari membran yang direndam dalam lantan HCl 0,1N selama 2 jam pada suhu kamar. Tingkat penyerapan membran tercangkok (PP-g-AA) terhadap ion-ion logam adalah Fe> Co> Cu >As> Cd> Pb. Akhirnya, suatu campuran yang terdiri atas tiga ion logam dalam larutan umpan digunakan untuk menentukan selektivitas membran terhadap ion-ion logam. Hasil yang diperoleh menunjukkan bahwa membran tercangkok mempunyai kemungkinan untuk digun","PeriodicalId":138501,"journal":{"name":"Jurnal Teknik Kimia Indonesia","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122730008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Formulasi sistematika knowledge-based engineering untuk penanganan permasalahan proses","authors":"Surahmad W Widodo, Yazid Bindar, P. Praharso","doi":"10.5614/jtki.2008.7.1.6","DOIUrl":"https://doi.org/10.5614/jtki.2008.7.1.6","url":null,"abstract":"Urea plant is a petrochemical plant considered as one of strategic industries in Indonesia. Knowledge is important asset for the company that should be managed well in order to give the optimal profit. Without the adequate knowledge to operate the process plant, the process problems tend to be solved by trial-error effort in the field with unknown result and can cause the losses for the company. With the knowledge-based system, the knowledge can be stored, organized can be accessed again to solve the process problem and minimize the trial-error losses in this thesis knowledge-based system formulation for process problem solving in urea synthesis process unit done by study the heuristic knowledge, study the urea synthesis equilibrium model, study the urea tray reactor with CFD simulation and study of development of process knowledge-based system model. Urea reaction equilibrium model used can explain the impact of temperature, NH3/C02 molar ratio and H2O/C02 molar ratio to the urea conversion. Calculation results of conversion and reactor outlet composition show the agreement with the reactor data. Results of CFD simulation show that the new configuration of reactor tray give the better mixing effect of liquid and gas phase than the conventional tray. Heuristic knowledge based on the experience and the knowledge based on process model become the knowledge base for development of knowledge-based system model for process problem solving.Keywords: knowledge-based, process knowledge, heuristic, simulation, CFD, urea reactor AbstrakPabrik pupuk adalah pabrik petrokimia yang termasuk salah satu industri strategis nasional. Pengetahuan merupakan aset penting bagi perusahaan yang harus dikelola sebaik-baiknya agar memberikan manfaat dan keuntungan yang optimal. Tanpa pengetahuan yang cukup dalam mengoperasikan pabrik, maka masalah proses yang dihadapi cenderung diselesaikan dengan percobaan di lapangan yang hasilnya tidak pasti dan mengakibatkan kerugian bagi perusahaan. Dengan sistem berbasis pengetahuan, maka pengetahuan disimpan, terorganisasi dan dapat diakses kembali untuk menyelesaian masalah proses, serta tindakan coba-coba yang menghasi/kan kesalahan dapat diminimalkan. Dalam tesis ini formulasi sistem berbasis pengetahuan untuk penanganan permasalahan proses pada unit reaktor sintesis urea dilakukan dengan melakukan kajian pengetahuan heuristis, kajian model kesetimbangan reaksi sintesis urea, kajian simulasi CFD tray reaktor, serta kajian model pengembangan sistem berbasis pengetahuan proses. Model kesetimbangan yang digunakan dapat menjelaskan pengaruh suhu, rasio NH3/CO2 dan rasio H20/C02 terhadap konversi. Hasil perhitungan untuk konversi dan komposisi keluaran reaktor menunjukkan kesesuaian dengan data rancangan pabrik. Hasil kajian simulasi CFD menunjukkan bahwa dengan konjigurasi tray baru dihasilkan efek pencampuran fasa cair dan gas yang lebih baik daripada dengan tray konvensional. Pengetahuan heuristis dari pengalaman dan pengetahuan b","PeriodicalId":138501,"journal":{"name":"Jurnal Teknik Kimia Indonesia","volume":"54 13","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120816928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"KOEFISIEN PERPINDAHAN MASSA VOLUMETRIS KESELURUHAN PADA EKSTRAKSI Cu DARI LARUTAN CuSO4.5H2O DENGAN TRIRUTYL PHOSPHATE-KEROSIN DALAM DOUBLE-STAGE MIXER-SETTLER","authors":"Panut Mulyono","doi":"10.5614/jtki.2008.7.1.4","DOIUrl":"https://doi.org/10.5614/jtki.2008.7.1.4","url":null,"abstract":"Copper has been extracted by trtbuthyl phosphate-kerosene from a dilute aqueous solution with a double- stage mixer-settler extraction column. The extraction column used in this experiment was made of glass. The mixer diameter was equal to the diameter of settler was 13 cm. Both the mixer and settler heights were 8 cm. Drop coalescer was mounted in the middle of mixer and settler separator. The diameter of drop coalescer was 6 cm with the thickness of 1 cm. The hole diameter of drop coalescer was 1 mm The stirrer used in this experiment was cross flat blade with the diameter and width of the impeller was 6 cm and 8 mm, respectively. The overall volumetric coefficient of mass transfer (Kca) increased by increasing the flowrate of the continuous phase (Lc) at the constants stirring speed (N) and flowrate of the dispersed phase (Ld). The increase of Lc from 4.1634 cm3/second to 17.9436 cm3/second increased the Kca value from 6.6387x10-5/second to 23.1561x10-5/second or 248.8% The value of Kca was also increase by increasing N at the constant values of Lc and Ld Thie increase of N from 3.3333 rps to 8.3333 rps increased the Kca value from 6.0288x10-5/second to 6.6387x10-5/second or 10.1%.Keywords: Mass Transfer Coefficient, Extraction, Copper, Double-Stage Mixer-SettlerAbstrak Penelitian ini mempelajari perpindahan massa antar fasa pada ekstraksi Cu dart larutan CuSO4.5H2O dengan menggunakan pelarut tributyl phosphate dalam kerosin yang dilakukan dalam kolom ekstraksi double-stage mixer-settler yang dtsusun vertikal. Kolom ekstraksi mixer-settler dibuat darti gelas dengan diameter mixer sama dengan diameter sealer, yaitu 13 cm. Tinggi mixer juga sama dengan tinggt settler, yaitu 8 cm. Diameter drop coalescer 8 cm, tebal 1 cm, dan diameter lubangnya 1 mm. Pengaduk yang digunakan berbentuk flat blade dengan diameter 6 cm dan lebar blade 8 mm. Koeftsien perpindahan massa volumetris keseluruhan (Kca) naik dengan naiknya kecepatan alir fasa kontinyu (Lc) pada kecepatan putaran pengaduk (N) dan kecepatan alir fasa dispersi (Ld) tetap. Kenatkan nilai Lc dart 4,1634 cm3/detik menjadi 17,9436 cm3/detik meningkatkan nilai Kca dart 6,6387x10-5/detik menjadi 23,1561x10-5/detik atau 248,8% Kca juga naik dengan naiknya N pada Lc dan Ld yang tetap. Kenaikan nilai N dart 3,3333 rps menjadi 8,3333 rps meningkatkan nilai Kca dart 6,0288x10-5/detik menjadt 6,6387x10-5/detik atau 10,1%.Kata Kunci : Koefesien Perpindahan Massa, Ekstraksi, Tembaga, Double-Stage Mixer-Settler","PeriodicalId":138501,"journal":{"name":"Jurnal Teknik Kimia Indonesia","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130297039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pengaruh penambahan tween 80, dekstrin, dan minyak kelapa pada pembuatan kopi instan menggunakan metode pengering busa","authors":"S SusianaPrasetyo, V. Vincentius","doi":"10.5614/jtki.2005.4.3.5","DOIUrl":"https://doi.org/10.5614/jtki.2005.4.3.5","url":null,"abstract":"The making of instant coffee with foam drying methods is one of the product inovation effort which it can produce commercially by small industry and also home industry. In this research, added coconut oil, dextrin, and tween 80 are added to the coffee for optimalized that drying process. Coconut oil are perhaps as heat conductor so that can increasing drying rate. Tween (Polyoxyethylene 20 Sorbitane Monooleate) and dextrin interacted each other tween 80 act as emulsifier and foam marker, dextrin act as foam stabilizer during drying process. Coffee extract have been added with cooconut oil, tween 80 and dextrin, they are mixed together toproduced  foam and then will be dried in cabinet drier. The research method used is the making an instant coffee in three differents coconut oil concentration (0.01-1 %w/w), three differents tween 80 concentration (5-15%w/w), and three differents dextrin concentration (0-20%w/w). The research results showed that added of coconut oil will be increased rate of drying. Tween 80 can increase rate of drying, but dextrin can make case hardening that decrease rate of drying. Product of instant coffee have water content and caffein content in the range of SNI, which are 2.281-3.962% of water and 2.825-3.275% of caffein. Flavor, taste and texture of instant coffee are not different from instant coffee in market.Keywords: Instant Coffee, Foam Drying, Tween 80, Dextrin, Coconut OilAbstrakPembuatan kopi instan menggunakan metodepengeringan busa (foam  drying) merupakan salah  satu usaha inovasi produk yang dapat dilakukan secara komersial oleh industri kecil ataupun home industry. Pada penelitian ini ditambahkan minyak kelapa, dekstrin dan tween 80 pada kopi untuk mengoptimalkan proses perngeringan tersebut. Minyak kelapa diharapkan dapat berperan sebagai penghantar panas sehingga dapat mempercepat pengeringan. Tween (Polyoxyethylene 20 Sorbitane Monooleate) dan dekestrin saling berinteraksi, dimana tween 80 berfungsi sebagai emulsifier dan pembentuk busa sedangkan dekstrin berperan sebagai penstabil busa selama proses pengeringan. Ekstrak kopi ditambahkan pada minyak kelapa, tween 80 dan de/estrin, dan diaduk hingga terbentuk busa untuk kemudian dioleskan pada tray-trayyang akhirnya akan mengalami proses pengeringan di dalam tray drier. Konsentrasi minyak kelapa divariasikan pada 0,01-1%b/b, tween 80 pada 5-15% b/b, dan dekstrin pada 10-20% b/b. Hasil penelitian menunjukkan bahwapenambahan minyak kelapa akan meningkatkan laju pengeringan. Penambahan dekstrin meningkatkan laju pengeringan sedangkan penambahan tween 80 akan menyebabkan case hardening dan menurunkan laju pengeringan. Kopi instan yang dihasilkan telah memenuhi standar SNI dengan kadar air 2,281- 3,962% dan kadar kafein 2,825-3,275% serta memiliki aroma, rasa dan tekstur yang tidak berbeda jauh dari kopi instan dipasaran.Kata Kunci: Kopi Instan, Pengering Busa, Tween 80, Dekstrin, Minyak Kelapa","PeriodicalId":138501,"journal":{"name":"Jurnal Teknik Kimia Indonesia","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128335893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of cell concentration and coal pretreatment on desulfurization of cigalugur subbituminous coal using thiobacillus ferrooxidans","authors":"D. Sasongko, A. A. Sjamsuriputra, M. Taufik, Alexis Airin","doi":"10.5614/jtki.2008.7.1.2","DOIUrl":"https://doi.org/10.5614/jtki.2008.7.1.2","url":null,"abstract":"The use of coal is forecast to increase substantially to generate energy through combustion. Coal contains chemical substances that might pollute environment if it is not properly burnt, such as sulfur and nitrogen. Sulfur removal can be carried out by chemical, physical, or biological methods. Removal of sulfur from coal by microbial action has many advantages over physical and chemical desulfurization methods, namely (i) low capital and operating cost, (ii) low energy requirements, and (iii) removal of finely dispersed sulfur. This paper reports an experimental study investigating the effects of microbial cell concentration and pretreatment of coal on sulfur removal from Indonesian subbituminous coal using Thiobacillus ferrooxidans. The experiments were conducted under conditions that promote performance of the microorganism, i.e. temperature of 28°C and pH of 2.5. The procedure includes blending coal with Thiobacillus ferrooxidans in a laboratory scale reactor. Coal particles were sampled periodically during bio desulfurization. Its sulfur content was then measured according to ASTM D2492-90 (for pyretic sulfur) and ASTM D4239-94 (for total sulfur). Experimental findings show that sterilized coals give higher sulfur removal (49.8% for pyretic sulfur and 39.5% for total sulfur) than those non-sterilized (30.2% for pyretic sulfur and 34% for total sulfur). Furthermore, observed cell concentration and percentage of sulfur removal (for pyretic and total sulfur) decrease with initial microbial cell concentration. Keywords: coal, biodesulfurization, Thiobacillus ferrooxidans AbstrakPenggunaan batubara diramalkan akan meningkat secara pesat untuk membangkitkan energi melalui pembakaran. Batubara mengandung senyawa-senyawa yang dapat mencemari lingkungan apabila tidak dibakar secara tuntas, seperti sulfur dan nitrogen. Penghilangan sulfur dapat dilaksanakan secara kimiawi, fisik, maupun biologik. Penghilangan sulfur dari batubara melalui proses mikrobial menunjukkan banyak kelebihan dibandingkan dengan metode-metode desulfurisasi fisik dan kimiawi, yakni (i) biaya modal dan operasi yang rendah, (ii) kebutuhan energi yang rendah, dan (iii) kemampuan penghilangan sulfur yang terdispersi secara halus. Tulisan ini membahas kajian eksperimental mengenai pengaruh konsentrasi sel mikroba dan perlakuan awal batubara terhadap penghilangan sulfur dari batubara sub-bituminus Indonesia, oleh bakteri Thiobacillus ferooxidans. Percobaan dilaksanakan dalam kondisi yang mendorong kinerja bakteri, yakni temperatur sebesar 28°C dan pH sebesar 2,5. Prosedur percobaan mencakup pencampuran batubara dengan Thiobacillus ferooxidans dalam reaktor berskala laboratorium. Partikel batubara dicuplik secara berkala selama proses biodesulfurisasi. Kandungan sulfurnya kemudian diukur dengan metode ASTM D2492-90 (untuk sulfur pirit) dan ASTM D4239-94 (untuk sulfur total). Hasil percobaan menunjukkan bahwa batubara yang disterilisasi memberikan penurunan kadar sulfur terbesar (49,8% ","PeriodicalId":138501,"journal":{"name":"Jurnal Teknik Kimia Indonesia","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125319908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Base case simulation of a semi-batch emulsion copolymerization process: application to styrene/ butadiene system","authors":"I. Harsono, H. Hindarso, N. Indraswati","doi":"10.5614/jtki.2005.4.3.6","DOIUrl":"https://doi.org/10.5614/jtki.2005.4.3.6","url":null,"abstract":"It has been long recognized that emulsion polymerization is a complex heterogeneous process involving transport of monomers, free radicals, and other species between aqueous phase and organic phase. Though there are a number of models available in the literature, most of them deal only with specific aspects in emulsion polymerization and are far from being general. To simulate this complicated process and to achieve an adequate level of understanding, a Polymers Plus software from Aspen Technology. Inc. was used. The objective of this work is to illustrate the principle of use of Polymers Plus, simulate, and analyze the free-radical seeded emulsion copolymerization of styrene­butadiene process model in a semi-batch reactor. The base case simulation can be used to gain process understanding by analyzing how process variables and operating conditions during the course of a semi-batch reactor affect the product quality.Keywords: Polymers Plus, Emulsion Copolymerization, Simulation, Semi Batch Reactor, Styrene/ butadiene AbstrakTelah diketahui sejak lama bahwa polimerisasi emulsi merupakan sebuah proses heterogen yang kompleks, yang meliputi perpindahan monomer, radikal bebas, dan senyawa lainnya dalam fasa air dan fasa organik. Walaupun dalam literatur terdapat berbagai model, sebagian besar hanya membahas tentang aspek-aspek khusus dalam polimerisasi emulsi yang belurn berlaku umum. Untuk melakukan simulasi serta meningkatkan pemahaman tentang proses yang kompleks ini, digunakan perangkat lunak Polymers Plus dari Aspen Technology, Inc. Penelitian ini bertujuan untuk memberikan ilustrasi tentang prinsip penggunaan Polymers Plus serta melakukan simulasi dan analisis tentang model untuk proses kopolimerisasi emulsi styrene-butadiene dengan free radical seeded dalam reaktor semi batch. Simulasi ini dapat digunakan untuk memperoleh pemahaman proses dengan menganalisis pengaruh variabel-variabel proses dan kondisi operasi dalam reaktor semi batch terhadap kualitas produk.Kata Kunci: Polymers Plus, Kopolimerisasi Emulsi, Simulasi, Reaktor Semi Batch, Stiren/ butadien","PeriodicalId":138501,"journal":{"name":"Jurnal Teknik Kimia Indonesia","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115716782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pengukuran solubilitas n-amylalkohol dalam poly (n-butyl methacrylate) dan polyisobutylene menggunakan metode piezoelectric-quartz crystal microbalance sorption","authors":"G. Wibawa, R. Lestari, Sofia Wardhani","doi":"10.5614/jtki.2005.4.3.1","DOIUrl":"https://doi.org/10.5614/jtki.2005.4.3.1","url":null,"abstract":"The Piezoelectric Quartz Crystal Microbalance (QCM) method was used to measure the solubilities of n-amylalcohol in poly (n-butyl methac1ylate) and polyisobutylene at temperatures of 333.15 K, 353.15 K and 353.15 K. The crystals used were 5 MHz, AT-Cut, 5.5 mm in diameter and 0.3 mm in thick. Reliability of the measurements was comfirmed by comparing the present data with the literature data for the system of benzene-polyisobutylene at temperature 338.15K. The solubilities n-amyl alcohol in polyisobutylene were undectedable in the range of temperature experiments by the present apparatus because of the low solubility. For the solubilities of n-amyl alcohol in ploy (n-butyl methacryalate) the higher temperature, the lower solubility and the experimental data could be correlated by the UNIQUAC equation with average absolute deviation between experimental and calculated solvent activities of 3.8%. Keywords: Solubility, Quartz Crystal Microbalance, Solvent, Polymer AbstrakDalam penelitian ini, metode Piezoelectric Quartz Crystal Microbalance (QCM) digunakan untuk mengukur kelarutan pelarut n-amylalkohol dalam polimer poly (n-butyl methacrylate) dan polyisobutylene pada temperatur 333,15 K, 343,15 K dan 353,15 K. Kristal yang digunakan adalah jenis AT-Cut 5 MHz, diameter 5,5 mm dan ketebalan 0,3 mm. Reliabilitas dari pengukuran di tes dengan membandingkan hasil pengukuran dengan data literatur untuk sistem benzene­polyisobutylene pada temperatur 338, I 5K. Kelarutan n-amyl alkohol dalam polyisobutylene tidak dapat terdeteksi pada range temperatur eksperimen dengan peralatan yang ada karena kelarutannya rendah. Untuk kelarutan n-amylalkohol dalam poly(n-butyl methacrylate), semakin besar suhu, kelarutannya semakin rendah dan data eksperimen dapat dikorelasikan menggunakan persamaan UNIQUAC dengan rata-rata deviasi ahsolut sebesar 3,8%.Kata Kunci: Kelarutan, Quartz Crystal Microbalance, Pelarut, Polimer","PeriodicalId":138501,"journal":{"name":"Jurnal Teknik Kimia Indonesia","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122025636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Membran PVA-chitosan crosslinked untuk pemisahan campuran etanol-air secara pervaporasi","authors":"I. Noezar","doi":"10.5614/jtki.2008.7.1.3","DOIUrl":"https://doi.org/10.5614/jtki.2008.7.1.3","url":null,"abstract":"One of the technologies for ethanol-water separation is pervaporation. The principles of pervaporation is based on the difference in diffusional rate and solubility of the solution components in membranes. The performance of the membrane, in terms of flux and selectivity, is influenced by the swelling of the membrane due to the interaction between the solution components and the membrane materials.  Membrane modification is done by forming chemical bonding between PVA and chitosan, using glutaraldehyde as crosslinking agent. The performance of the PVA-chitosan   crosslinked membrane for ethanol-water separation is characterized by high mass flux and   reasonably high selectivity. Pressure observed on the permeate side was 0.5 mbar, with a feed ethanol concentration of 93%. Experimental results indicate that the PVA membrane has a higher degree of swelling compared to the crosslinked PVA-chitosan membrane. The PVA-chitosan crosslinked membrane has a higher selectivity compared to the PVA membrane. The highest flux of 0.833 kgm-2hour-1 was produced by the PVA membrane. The highest selectivity of 2.820 was obtained using a 1:1 PVA-chitosan crosslinked membrane.Keywords: PVA-chitosan; crosslinked; pervaporation Abstrak Salah satu teknologi untuk pemisahan etanol-air adalah pervaporasi. Prinsip pemisahan pervaporasi adalah dengan perbedaan laju difusi dan kelarutan komponen campuran pada membran. Kinerja membran berupa fluks dan selektivitas dipengaruhi oleh kondisi swelling membran akibat interaksi komponen dengan material membran. Modifikasi membran dilakukan dengan membentuk ikatan kimia antara PVA dan chitosan dengan glutaraldehid sebagai crosslinking agent. Kinerja membran PVA-Chitosan crosslinked dalam pemisahan campuran etanol-air berupa fluks massa yang tinggi dan selektivitas yang cukup besar. Tekanan pada sisi permeat 0,5 mbar dengan konsentrasi etanol umpan 93%. Hasil penelitian menunjukkan membran PVA memiliki nilai derajat swelling lebih tinggi (0,088) daripada membran PVA-Chitosan crosslinked. Membran PVA-Chitosan crosslinked memiliki selektivitas lebih tinggi daripada membran PVA. Fluks terbesar dimiliki oleh membran PVA senilai 0,833 kgm-2jam-1membran PVA-Chitosan crosslinked 1:1 sebesar 2.820.Kata Kunci : PVA-Chitosan; crosslinked; pervaporasi","PeriodicalId":138501,"journal":{"name":"Jurnal Teknik Kimia Indonesia","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126910700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}