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All Journal Jurnal Rekayasa Proses Jurnal MEKANIKAL Reaktor International Journal of Science and Engineering (IJSE) TEKNIK Jurnal Kesehatan Lingkungan indonesia JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik Bulletin of Chemical Reaction Engineering & Catalysis Majalah Ilmiah MOMENTUM Emerging Science Journal Indonesian Journal of Chemistry JURNAL PANGAN Jurnal Pasopati : Pengabdian Masyarakat dan Inovasi Pengembangan Teknologi Bulletin of Chemical Reaction Engineering & Catalysis
Ratnawati Ratnawati
Department Of Chemical Engineering Faculty Of Engineering Diponegoro University
Aerospace Engineering Agriculture, Biological Sciences & Forestry Automotive Engineering Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Earth & Planetary Sciences Education Electrical & Electronics Engineering Energy Engineering Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mechanical Engineering Public Health Social Sciences

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Journal : TEKNIK

 1 
Modifikasi Pati Sukun (Artocarpus Altilis) dengan Teknik Oksidasi Menggunakan Hidrogen Peroksida Tanpa Katalis Budiyati, Catarina Sri; Kumoro, Andri Cahyo; Ratnawati, Ratnawati; Retnowati, Diah Susetyo
TEKNIK Vol 37, No 1 (2016): (Juli 2016)
Publisher : Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1232.848 KB) | DOI: 10.14710/teknik.v37i1.9832

Abstract

Salah satu sumber bahan pangan lokal yang belum banyak dimanfaatkan adalah buah sukun (Artocarpus Artilis) yang cukup banyak terdapat di Indonesia. Akan tetapi, pemanfaatan buah sukun terkendala pada kurangnya daya simpan buah segar. Oleh karena itu, perlu dilakukan upaya untuk meningkatkan pemanfaatan buah sukun dengan mengolahnya menjadi produk yang lebih luwes dengan daya simpan yang lebih baik, yaitu menjadi pati sukun. Sifat-sifat pati sukun perlu diperbaiki agar dapat digunakan sebagai pengganti tepung terigu. Tujuan dari penelitian ini adalah untuk memodifikasi pati sukun dengan cara oksidasi menggunakan larutan hidrogen peroksida. Dalam penelitian ini dikaji pengaruh konsistensi luluhan, konsentrasi hidrogen peroksida, waktu, dan suhu terhadap karakteristik fisikokimia pati sukun teroksidasi yang dihasilkan dan ditentukan kondisi optimalnya. Hasil penelitian menunjukkan bahwa semua variable yang dikaji tersebut mempengaruhi reaksi oksidasi pati sukun. Oksidasi pada konsistensi luluhan 20%, konsentrasi hidrogen peroksida 2% dan suhu 50°C mampu menghasilkan nilai swelling power dan water solubility yang terbaik. Reaksi oksidasi tidak mengubah struktur dan morfologi pati sukun termodifikasi secara signifikan.   [Title: Modification of Breadfruit (Artocarpus altilis) starch through non-catalytic hydrogen peroxide oxidation] One of local source of food that has not been intensively explored is breadfruit (Artocarpus Artilis). However, the utilization of breadfruit is limited by the poor storage properties of the fresh fruit. Therefore, efforts should be made to improve the utilization of breadfruit to process it into more flexible products with better storability, suach as breadfruit starch. Breadfruit starch properties need to be improved so that it can be used to substitute wheat flour. The aim of this study was to modify the breadfruit starch by oxidation using hydrogen peroxide solution. This work studied examined the influence of consistency of starch slurry, hydrogen peroxide concentration, time, and temperature on the physicochemical properties of the oxidized breadfruit starch. The optimal conditions were also determined. The results showed that all of these variables affected the oxidation of starch breadfruit. The oxidation on starch slurry with consistency 20%, the concentration of hydrogen peroxide of 2%, and temperature of 50°C produced modified starch with best swelling power and water solubility. The oxidation did not significantly change the structure and morphology of the modified starch.
RECOVERY GARAM LITHIUM DARI AIR ASIN (BRINE) DENGAN METODA PRESIPITASI Sumarno, Sumarno; Ratnawati, Ratnawati; A. Nugroho, A. Nugroho
TEKNIK Volume 33, Nomor 2, Tahun 2012
Publisher : Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (51.65 KB) | DOI: 10.14710/teknik.v33i2.4387

Abstract

Lithium demand increases as it is widely used as raw material for rechargeable battery, alloy for airplane, andfuel for fusion nuclear reactor. Lithium is an extremely reactive element, that it is never found as free element innature. Lithium compounds are found in earth crust, with very small concentration (20 – 70 ppm) and totalcontent of more than 20 million tons. The biggest lithium reserve is in seawater (0,14 – 0,25 ppm) andgeothermal water (7 ppm) with total amount of 230 billion tons. There is no industry applies the technology torecover lithium from seawater. Having a vast sea area and abundant geothermal sources, Indonesia needs todevelop a technology to recover lithium from both sources. This research is aimed to recover lithium fromgeothermal water. The experiment was conducted using synthetic and geothermal water with lithiumconcentration range of 220 – 400 ppm, temperature range of 20 – 40°C, and mixing time range of 1 – 4 hours.The experiment was designed with 2 level factorial design. The results show that the most influencing variable ismixing time, while significant interaction amongst variables is not observed. Further experiment usinggeothermal water from Bledug Kuwu with initial lithium concentration of 400 ppm and temperature 30°Cresulted in optimum mixing time, i.e. 3 hours with 92,5% of the lithium could be recovered
KONVERSI ELEKTROKIMIA AMONIA MENJADI HIDROGEN Ratnawati, Ratnawati; Sumarno, Sumarno; Nugroho, Amin
TEKNIK Volume 31, Nomor 2, Tahun 2010
Publisher : Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (180.368 KB) | DOI: 10.14710/teknik.v31i2.1771

Abstract

One of the most dangerous pollutants in wastewater is ammonia. The concentration of ammonia inwastewater discharged from nitrogen fertilizer industry is up to 1500 ppm. Ammonia can be removed byseveral methods such as biological denitrification, air-stripping, and ion exchange. The methods cannotreduce the concentration of ammonia to a low level as required for standard quality of wastewater. Theelectrochemical method has recently attracted attention for the treatment of wastewater containing ammonia.This research is aimed to evaluate the effect of ammonia concentration, current density, and time on theelectrolysis process. Synthetic wastewater containing 500-1500 ppm of ammonia was used in this research.The solution was electrolyzed in a electrolytic cell with Pt/SS electrodes. The experiment was conducted byvarying current density in the range of 5 – 10 mA/cm2 and time from 0 to 105 minutes. The experiment resultsshow that as current density rises, the electrolytic reaction occurs more rapidly. On the other hand, initialconcentration of ammonia has negative effect on the final conversion of ammonia.
Co-Authors . Widayat A. Nugroho A. Nugroho Aat Zaki Mubarok Affian Widjanarko Affian Widjanarko Aji Prasetyaningrum Amin Nugroho Andri C. Kumoro Andri Cahyo Kumoro anggoro D.D. Anggoro Anita Pinalia Aprilina Purbasari Bakti Jos Bayu Prianto Catarina S. Budiyati Catarina Sri Budiyati Cindi Yasintasia Dewi Ayuningtyas Diah S. Retnowati Diah Susetyo Retnowati Djoko Mulyono Dyah Arum Kusumaningtyas Dyah Hesti Wardhani Fadlillah Fani Fitri Lafifa G.A. Mansoori G.A. Mansoori Gian Restu Prinanda H Hadiyanto Hargono Hargono Hartono, Damin Henny Setyaningsih Jefri Chandra Runanda Johannes Leonard Jumali Jumali L. Buchori Lestari, Novi Dian Luqman Buchori M. Djaeni Maharani Ratridewi Maria Augustine Graciafernandy Nafiah Amalia Nita Indriyani Nita Indriyani Noer Abyor Handayani Noor Hidayati Nur Rokhati Nurfiningsih Nurfiningsih Nurkhikmah, Eli Nurul Asiah Nurul Asiah Prawita Dhewi Purbo Suseno R Ridwan R. Ridwan Retno Wulandari Rizky Adi N Sadam Arrois Siti Thomas Zulaikhah Suherman Suherman Sulastri, Neng Sumarno . Teguh Riyanto Utami Diah P. Wiratno Wiratno Yudhy Dharmawan Yustina Linasari