Jurnal Kimia Valensi最新文献

{"title":"Synthesis and Characterization of Ag/TiO2 Nanoparticles using Mirabilis jalapa Plant Extract","authors":"F. O. Purnomo, S. S. Ningrum, Sadwika Najmi Kautsari","doi":"10.15408/JKV.V1I1.18875","DOIUrl":"https://doi.org/10.15408/JKV.V1I1.18875","url":null,"abstract":"Green synthesized nanomaterials have been widely developed because of their less toxicity, low energy process, environmentally friendly, effective, cheap, and pollution-free. Green synthesis of silver doped titanium dioxide nanoparticles (Ag/TiO2 NPs) was carried out using Mirabilis jalapa plant extract. The plant extract was used as a reducing agent. The functional groups, morphology, and crystalline structure of as-synthesized Ag/TiO2 NPs were investigated by FT-IR, FESEM, and XRD. Analysis by FESEM confirmed that the morphology of Ag/TiO2 NPs is spherical with an average size of ~ 400 nm. Crystallite size for the Ag/TiO2 NPs was calculated by the Scherrer formula dan the average size found to be in the range of 15.72 nm. The result of XRD analysis showing the fcc structure for metallic silver and TiO2 particles in the anatase and rutile phases.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43086581","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":"Nanoporous Carbon Prepared with MOF-5 as a Template and Activated using KOH for Hydrogen Storage","authors":"R. Ediati, T. Mulyati, A. Mukminin, D. O. Sulistiono, N. Khoiroh, H. Fansuri, D. Prasetyoko","doi":"10.15408/jkv.v6i1.13621","DOIUrl":"https://doi.org/10.15408/jkv.v6i1.13621","url":null,"abstract":"A series of nanoporous carbon was prepared with MOF-5 as a template and furfuryl alcohol as an additional carbon source by carbonation at temperatures of 550 °C and 900 °C, respectively, with and without activation using KOH. XRD patterns of the obtained carbons before and after the activation process showed characteristic peaks at the same 2θ values, which corresponded to the XRD pattern of a ZnO. The Surface morphology of the MOF-5 templated carbon with a carbonation temperature of 550 °C was in the form of a cube. In contrast, the one carbonated at 900 °C had a cubic and circular morphology. The N2 adsorption-desorption isothermal showed that MOF-5 templated carbon had a larger specific surface area, pore diameter, and pore volume than those of the original MOF-5. Activation of the MOF-5 templated carbon using KOH resulted in a decrease in surface area and pore volume. All the materials were measured for their hydrogen adsorption at room temperature and atmospheric pressure using a gravimetric method.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43724675","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":"Silver Recovery from X-ray Film Waste by Leaching and Precipitation Method Using Sodium Hydroxide and Sodium Sulfide","authors":"S. Fatimah, W. Siswaningsih, Ali Kusrijadi, Fikri Aziz Shalahuddin","doi":"10.15408/jkv.v6i1.13648","DOIUrl":"https://doi.org/10.15408/jkv.v6i1.13648","url":null,"abstract":"Silver recovery research from x-ray film waste by leaching and precipitation method using NaOH and Na2S aims to determine the optimum conditions in silver recovery. The parameters optimated in this study were the concentration of the precipitants, leaching temperature and the effect of the type of precipitants on the precipitated time. The results showed that the NaOH and Na2S precipitants were able to recover silver optimally at a concentration of 1.5 M. The optimum leaching temperature of the film with the Na2S precipitant to recover silver was at 25oC, whereas in the NaOH precipitant the film leaching temperature only affected the time of precipitation. Therefore, the formation of precipitate using Na2S is more efficient than NaOH, but the acquisition of silver is better to use NaOH than Na2S.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46303205","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":"The Effect of Single Co-expression of The DnaK-DnaJ-GrpE and GroEL/ES Chaperones and Their Combination on Expression Intein-pretrombin-2 in Escherichia coli ER2566","authors":"I. Maksum, D Agus Yusuf Wildan, Khomaini Hasan, T. Subroto","doi":"10.15408/jkv.v6i1.11333","DOIUrl":"https://doi.org/10.15408/jkv.v6i1.11333","url":null,"abstract":"The use of recombinant thrombin in the manufacture of fibrin glue allows diseases contamination to be avoided. However, the expression of recombinant protein in E. coli still has a disadvantage of the formation of inclusion bodies, so it needs to be minimized by co-expression of chaperones. Therefore, the aim of this study was to determine the effect of single DnaK-DnaJ-GrpE and GroEL/ES chaperone expression and their combination on the expression of intein-pretrombin-2Ti,pH on E. coli ER2566. The method started with isolation of pTWIN1-prethrombin-2Ti,pH and pG-KJE8 from E. coli TOP10F' and DH5α respectively, the co-transformation of the expression host E. coli ER2566 using pG-KJE8 and pTWIN1-prethrombin-2Ti,pHvectors, the chaperone co-expression was induced using L-Arabinosa before IPTG induction and cell culture growth was incubated at 22 oC. The expression products were characterized by using Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The results of the co-expression of chaperone showed that the number of soluble fraction was higher than the one without co-expression of chaperone. In addition, the co-expression of chaperone using pG-KJE8 in intein-prothrombin-2Ti,pH expression was sufficient using tetracycline as an inducer.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67112679","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":"Degradasi Zat Warna Orange-F3R dan Violet-3B secara Sonolisis Frekuensi Rendah dengan Penambahan Katalis C-N-Codoped TiO2","authors":"Reza Audina Putri, Safni Safni, Diana Vanda Wellia, Upita Septiani, N. Jamarun","doi":"10.15408/JKV.V5I1.7801","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.7801","url":null,"abstract":"Zat warna orange-F3R dan violet-3B merupakan zat warna organik sintetis turunan vat yang bersifat non-biodegradable. Degradasi kedua zat warna ini telah dilakukan secara sonolisis dengan penambahan katalis semikonduktor TiO2 anatase yang didoping karbon dan nitrogen. Proses sonolisis menggunakan iradiasi ultrasonik dengan frekuensi 35 kHz. Massa katalis optimum yang diperoleh untuk sonolisis zat warna orange-F3R adalah 9 mg dan 6 mg untuk violet-3B. Persen degradasi meningkat secara signifikan dengan penambahan katalis yaitu dari 8.3% menjadi 36.2% untuk sonolisis zat warna orange-F3R selama iradiasi 180 menit. Sedangkan, dengan waktu iradiasi yang sama persen degradasi dari zat warna violet meningkat dari 5.8% menjadi 34.2% setelah penambahan katalis. Kata kunci: C-N-codoped TiO2, sonolisis, ultrasonik, vat  Orange-F3R and violet-3B are non-biodegradable synthetic organic dyes. The degradation of these two dyestuffs has been done by sonolysis process with the addition of semiconductor TiO2 anatase catalyst which is doped by carbon and nitrogen atoms. The sonolysis process used ultrasonic irradiation with a frequency of 35 kHz. The optimum catalyst mass obtained for the orange-F3R dye sonolysis was 9 mg and 6 mg for violet-3B. The percentage of degradation increased significantly with the addition of the catalyst; it was from 8.3% to 36.2% for the orange-F3R dye during irradiation for 180 min. Meanwhile, by the same irradiation time, the degradation percentage of violet dye increased from 5.8% to 34.2% after the addition of the catalyst. Keywords: C-N-codoped TiO2, sonolysis, ultrasonic, vat-dye.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44349082","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":"Profil Dan Sensitivitas Protein Alergen Ikan Tongkol (Thunnus albacares) Sebagai Reagen Skin Prick Test (SPT)","authors":"Sri Yadial Chalid, Dahrul Syah, Puspo Edi Giriwono, Fransiska Rungkat, Zakaria Zakaria","doi":"10.15408/JKV.V5I1.9678","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.9678","url":null,"abstract":"Ikan tongkol merupakan salah satu produk laut penyebab alergi makanan. Gejala klinis reaksi alergi makanan adalah gatal, bentol, bengkak, sesak nafas, batuk, dan yang terparah adalah syok anafilaksis. Pengobatan dan pencegahan alergi makanan yang terbaik adalah menghindari konsumsi penyebab alergi. Menghindari konsumsi suatu makanan sebaiknya berdasarkan uji alergi seperti Skin Prick Test (SPT). SPT dilakukan menggunakan reagen SPT yang dicukitkan pada lapisan epidermis kulit lengan bagian volar. Reagen alergen pada penelitian ini merupakan protein ikan tongkol yang berasal dari laut Indonesia dan diekstrak dengan buffer fosfat, Profil ekstrak protein menggunakan elektroforesis dan immunoblotting untuk menentukan protein allergen. Sebanyak 15 pita protein terdeteksi pada ekstrak ikan tongkol yaitu protein dengan berat molekul antara 17 sampai 152 kDa. Potensi alergenik terdapat pada pita protein dengan berat molekul antara 12 sampai 50 kDa. Reagen SPT ikan tongkol mempunyai sensitivitas sebesar 81.8% dan spesifitas 100% sehingga disimpulkan bahwa reagen ekstrak ikan tongkol dapat digunakan sebagai reagen skin prick test Kata kunci: Alergi, protein, tongkol, gejala klinis, skin prick test   Tuna fish is one of the marine products that can cause allergic. Clinical symptoms of allergic are a bump, swelling, shortness of breath, coughing and anaphylactic shock is the worst symptom. The best medication and treatment is avoiding the consumption of food that could cause allergy. Avoiding consumption of food should be based on an allergy test such as a Skin Prick Test (SPT). SPT using reagent which is applied on the skin of the forearm between the wrist and elbow. The reagent for SPT is a protein solution of tuna which was extracted by phosphate buffer then protein profile was detected using electrophoresis. Immunoblotting was done to determine the molecular weight of the allergen protein. Fifteen protein bands were detected on tuna fish extract; the molecular weight of the protein was obtained between 17 to 152 kDa. Protein allergenic are molecules that have protein bands with a molecular weight between 12 and 50 kDa. Tuna fish extract solution for SPT had a sensitivity is 81.8%, and specificity is 100%, it was concluded that tuna fish reagent could be used as SPT reagent. Keywords: Allergen, protein, tuna fish, skin prick test.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45975920","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":"Peran Capping Agent terhadap Morfologi SrTiO3 Bulat Berongga yang Terbentuk dari Susunan Nanokubus melalui Metode Solvotermal","authors":"Y. Putri, Merida Saputri, Rahmadhini Anwar, N. Andriani, Rathesa Najeela, Thalabul Ilmi, Diana Vanda Wellia","doi":"10.15408/JKV.V5I1.9972","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.9972","url":null,"abstract":"SrTiO3 bulat berongga yang tersusun dari nano kubus telah disintesis dengan penambahan cetyltrimethylammonium bromide (CTAB) sebagai capping agent untuk mengontrol morfologi partikel. Kondisi sintesis pada suhu 220 °C selama 48 jam dengan perbandingan mol Sr:Ti = 1:1.25 dan perbandingan material awal dengan CTAB adalah 1:0.5 menghasilkan partikel dengan kristalinitas yang tinggi pada puncak spesifik   2θ = 32.41o bidang 110 yang merujuk pada struktur perovskit kubus.  Penghalusan struktur kristal dengan metoda Rietveld menunjukkan bahwa struktur kristal hasil pengukuran memiliki kecocokan yang tinggi dengan hasil perhitungan dengan nilai Rwp adalah 12.07. Interaksi antara CTAB dan permukaan SrTiO3 terlacak pada spektrum FTIR dengan angka gelombang 1100-1250 cm-1 membuktikan adanya vibrasi ulur C-N yang melemah akibat proses capping. Foto SEM menunjukkan bahwa partikel yang terbentuk umumnya memiliki bentuk bulat berongga, sementara foto TEM memperlihatkan partikel berongga berukuran mikro dibentuk dari susunan nanokubus berukuran rata-rata 20 nm. Kata kunci: Capping agent, partikel berongga, nanokubus, solvotermal, perovskite The synthesis of SrTiO3 hollow sphere built as assembly of nanocubes using cetyltrimethylammonium bromide (CTAB) as capping agent was aimed to control the size and shape of the particles. The condition of the synthesis at 220 °C for 48 hours with a molar ratio of Sr:Ti was 1:1.25 and starting material:CTAB was 1:0.5, have resulted the particles with a high crystallinity with specific XRD peaks at 2θ; 32.41 (110), which was in agreement with the cube-perovskite structure. The refinement of the crystal structure by the Rietveld method showed that the crystal structure of the measurement results has a high match with the result of the calculation with Rwp value was 12.07. The interaction between CTAB and the surface of SrTiO3 traced in the FTIR spectrum with wave number 1100-1250 cm-1 indicated the stretching vibration of C-N was weakened due to the capping process. SEM images showed the particles with hollow microsphere, while TEM images revealed that the hollow particles were assembled by nanocubes with an average size of 20 nm. Keywords: Capping agent, hollow, nanocube, solvothermal, perovskite.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48916379","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":"Fitoremediasi Logam Seng (Zn) Menggunakan Hydrilla sp. Pada Limbah Industri Kertas","authors":"Cory Novi, Sartika Sartika, Afifah Nur Shobah","doi":"10.15408/JKV.V5I1.8814","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.8814","url":null,"abstract":"Logam seng pada konsentrasi tertentu dapat terakumulasi di dalam air, biota dan sedimen pada perairan yang dapat menimbulkan efek toksik terhadap organisme sehingga untuk mengatasi permasalahan tersebut telah dikembangkan teknologi alternatif yang dikenal dengan fitoremediasi. Tujuan dari penelitian ini adalah memanfaatkan Hydrilla sp. sebagai agen fitoremediasi untuk menurunkan konsentrasi logam seng (Zn) pada limbah industri kertas. Tahap penelitian meliputi uji karakteristik awal air limbah dan Range Finding Test (RFT), penyiapan 75 g Hydrilla sp. dan aklimatisasi Hydrilla sp. selama 5 hari. Hydrilla sp. ditumbuhkan  pada reaktor selama 18 hari dalam 5 liter limbah industri kertas dengan konsentrasi 100% dan 5 liter akuades sebagai kontrol (0%). Variabel pengamatan meliputi pengukuran nilai pH, suhu dan identifikasi perubahan warna daun Hydrilla sp. Limbah hasil fitoremediasi pada waktu pemaparan 3, 6, 9, 12, 15, dan 18 hari dilakukan analisis logam seng (Zn) dengan ICP-OES. Berdasarkan hasil analisis menunjukkan bahwa pada hari ke-0 sampai hari ke-12 persentase logam seng yang hilang sebesar 50% dan pada hari ke-18 mengalami penurunan persentase sebesar 25%. Kata kunci : Fitoremediasi, Hydrilla sp., limbah industri kertas, logam seng. Zinc metal at certain concentrations can accumulate in water, biota, sedimentary in waters which can cause toxic effects on organisms. So as to overcome these problems alternative technologies have been developed known as phytoremediation. The purpose of this research is to utilize Hydrilla sp. as a phytoremediation agent to reduce zinc metal concentrations in paper industry wastes. The research phase included preliminary research that is initial characteristic of wastewater and Range Finding Test (RFT), preparation of 75 g of Hydrilla sp. and Hydrilla sp. acclimatization for 5 days, then Hydrilla sp. grown on reactor for 18 days in 5 liters of paper industry waste with 100% concentration and 5 liters of akuadest as control (0%). Observation variables include measuring pH values, temperature and identify discoloration of Hydrilla sp. leaves, then the phytoremediation waste at exposure time of  3, 6, 9, 12, 15 and 18 days was analyzed zinc (Zn) with ICP-OES. Based on the analysis results show that on days 0 to day 12 the percent amount lost by 50% and on the 18th day the amount of zinc metal lost decreased by 25%. Keywords : Phytoremediation, Hydrilla sp., paper industry waste, zinc metals.","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49311155","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":"Aplikasi Urease dari Biji Kacang Tolo (Vigna unguiculata ssp unguiculata L.) untuk Biosensor Urea","authors":"Zusfahair Zusfahair, D. Ningsih, Amin Fatoni, Vika Aprilia Puspitarini","doi":"10.15408/JKV.V5I1.8776","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.8776","url":null,"abstract":"Penggunaan urease dalam analisis urea yang digabungkan dengan suatu transduser disebut biosensor urea.Tujuan penelitian adalah menentukan kadar urea dengan metode biosensor urea berbasis urease biji kacang tolo yang diamobilisasi pada matrik alginat dan dideteksi secara kolorimetri menggunakan indikator bromtimol biru. Penelitian dimulai dengan isolasi urease dari biji kacang tolo (Vigna unguiculata ssp unguiculata L.), kemudian diamobilisasi menggunakan metode penjebakan dengan natrium alginat, setelah mencampur larutan urease dengan natrium alginat, diteteskan dalam larutan CaCl2 sampai terbentuk urease alginat. Beads urease alginat direaksikan dengan urea menghasilkan ion amonium, selanjutnya ditambahkan indikator bromtimol biru dan perubahan warnanya diukur menggunakan spektrofotometer. Kinerja analitis biosensor urea ditentukan melalui penentuan waktu reaksi enzimatis, keberulangan analisis, keberulangan pembuatan dan pengujian senyawa penganggu dengan konsentrasi urea 4mM, serta penentuan linearitas, batas deteksi, dan batas kuantifikasi dengan konsentrasi urea 0.05; 1; 3; 7; dan 15 mM. Hasil penelitian menunjukkan beads urease alginat bisa digunakan berulang sampai 8 kali. Kinerja analitis beads urease alginat menghasilkan respon yang linier pada rentang 0.05-15 mM dengan koefisien korelasi sebesar 0.9981, batas deteksi sebesar 0.8 mM dan batas kuantifikasi sebesar 2.67 mM. Keberulangan pembuatan beads urease alginat menghasilkan nilai koefisien variasi sebesar 6%. Analisis tidak terganggu dengan keberadaan asam askobat 0.05 mM dan asam urat 0.4 mM. Kata kunci: Amobilisasi urease, beads alginat, biosensor, biji kacang tolo, spektrofotometri. The use of urease in the urea analysis which combined with a transducer is called urea biosensor. Research aimed to determine urea level using urea biosensor method based on urease from black-eyed pea that immobilized on alginate matrix and detected by colorimetric using bromothymol blue indicator. The research began with urease isolation from black-eyed pea (Vigna unguiculata ssp unguiculata L.), and then it immobilized utilizing the trapping method with sodium alginate, after mixing urease solution with sodium alginate, it is dripped in CaCl2 solution until alginate urease beads formed. Alginate urease beads reacted with urea to produce ammonium ion, then it’s added with indicator bromothymol blue, and the color changes were measured using a spectrophotometer. ­The analytical performance of urea biosensor is determined by enzymatic reaction time, repeated analysis, repeatability of fabrication and calibration of disturbing compound with concentration of urea 4 mM, also linearity, limit of detection and limit of quantification with concentration of urea 0.05, 1, 3, 7 and 15 mM. The results showed that alginate urease beads could repeatedly be used until eight times. The analytical performance of alginate urease beads including a linear response in the range of 0.05 mM-15 mM with the correlation coeffi","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42634066","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":"Upgrading Crude Biodiesel dari Minyak Goreng Bekas menggunakan Katalis H-Zeolit","authors":"Isalmi Aziz, Muhammad Akbar Tafdila, Siti Nurbayti, Lisa Adhani, W. Permata","doi":"10.15408/JKV.V5I1.10493","DOIUrl":"https://doi.org/10.15408/JKV.V5I1.10493","url":null,"abstract":"Crude biodiesel hasil transesterifikasi minyak goreng bekas dapat ditingkatkan kualitasnya melalui proses catalytic cracking menggunakan zeolit alam. Penelitian ini bertujuan untuk menentukan kondisi optimum proses catalytic cracking dan sifat fisika dan kimia biofuel yang dihasilkan. Reaksi dijalankan dalam reaktor dengan memvariasikan waktu (1, 2 dan 3 jam), konsentrasi katalis (3, 5 dan 7 %), ukuran partikel katalis (180, 250 dan 630μm) dan suhu reaksi (325, 350 dan 375°C). Kondisi optimum proses catalytic cracking crude biodiesel didapatkan pada : waktu  3 jam, konsentrasi katalis 7%, ukuran partikel katalis 180 μm dan suhu reaksi 375°C. Biofuel yang dihasilkan mengandung 6,26% fraksi bensin(C5-C11); 17,6% kerosin (C12-C15), 47,73% biodiesel (C16-C20) dan asam lemak 28,4%. Analisis sifat fisik menunjukan densitas 0,9631g/mL, titik tuang 12°C, titik nyala  49°C dan angka oktan 72,6. Kata kunci: catalytic cracking, crude biodiesel, angka oktan, biofuel. Crude biodiesel from transesterification of used cooking oil can be improved in quality through catalytic cracking using natural zeolite. This study aims to determine the optimum conditions for catalytic cracking and the physical and chemical properties of biofuels produced. The reaction was carried out in the reactor by varying the time (1, 2 and 3 hours), catalyst concentration (3, 5 and 7%), catalyst particle size (180, 250 and 630 μm) and reaction temperature (325, 350 and 375°C) . The optimum conditions for the catalytic cracking crude biodiesel process were obtained at: 3 hours, 7% catalyst concentration, catalyst particle size 180 μm and reaction temperature 375 ° C. The resulting biofuel contains 6.26% gasoline fraction (C5-C11); 17.6% kerosene (C12-C15), 47.73% biodiesel (C16-C20) and fatty acids 28.4%. Physical properties analysis showed density of 0.9631g/mL, pour point 12°C, flash point 49°C and octane number 72.6. Keywords: Catalytic cracking, crude biodiesel, octane number, biofuel. ","PeriodicalId":17786,"journal":{"name":"Jurnal Kimia Valensi","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44192325","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}