Article Per Year (5 Year)
p-Index From 2021 - 2026
0.778
P-Index
This Author published in this journals
All Journal Reaktor International Journal of Science and Engineering (IJSE) JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Jurnal Aplikasi Teknologi Pangan Indonesian Journal of Chemistry ASEAN Journal of Chemical Engineering Jurnal Pasopati : Pengabdian Masyarakat dan Inovasi Pengembangan Teknologi International Journal of Renewable Energy Development Bulletin of Chemical Reaction Engineering & Catalysis
Aji Prasetyaningrum
Chemical Engineering Department, Faculty Of Engineering, Diponegoro University, Jl. Prof. Sudarto, Tembalang-Semarang, 50275, Telp/fax: (024)7460058/(024)76480675
Aerospace Engineering Agriculture, Biological Sciences & Forestry Automotive Engineering Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Control & Systems Engineering Earth & Planetary Sciences Electrical & Electronics Engineering Energy Engineering Environmental Science Immunology & microbiology Industrial & Manufacturing Engineering Materials Science & Nanotechnology Other

Published : 18 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search
Journal : Bulletin of Chemical Reaction Engineering

 1 
UV Irradiation and Ozone Treatment of κ-Carrageenan: Kinetics and Products Characteristics Aji Prasetyaningrum; Widayat Widayat; Bakti Jos; Yudhy Dharmawan; Ratnawati Ratnawati
Bulletin of Chemical Reaction Engineering & Catalysis 2020: BCREC Volume 15 Issue 2 Year 2020 (August 2020)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.15.2.7047.319-330

Abstract

The low molecular weight (LMW) of sulfated polysaccharides including k-carrageenan, is shows a wide spectrum of biological activities. This research investigates the influence of UV irradiation, ozone (O3), and the combination of O3/UV methods on the depolymerization of k-carrageenan. The depolymerization kinetics of k-carrageenan using the Advanced Oxidation Process (UV/O3) was also studied. Furthermore, the intrinsic viscosity method was used to determine the average molecular weight of the research sample, and a mathematical model was developed to predict the kinetic rate constant, as a function of ozone dosage and UV irradiation intensity. Therefore, the physicochemical and morphological properties of the degraded k-carrageenan were analyzed by FT-IR, SEM, and XRD. The intrinsic viscosity k-carrageenan decreases with increasing UV light intensity and ozone concentration. The combination of UV/O3 treatment appeared to be more effective than the individual approaches, as the highest kinetic rate constant for depolymerization was 1.924×10-4 min-1, using 125 mg/L ozone concentration and 40 mW/cm2 of UV lamp intensity. This research also evaluated the relationship between various experimental conditions, including UV lamp power dissipation and ozone concentration on the reaction kinetics model, and the results suggest that lower effect is contributed by UV irradiation intensity. In addition, FT-IR spectra showed the absence of any significant change in the functional properties of k-carrageenan treated with UV and O3 processes, although the morphological properties of the LMW k-carrageenan were rougher and more porous than the native k-carrageenan. Copyright © 2020 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Kinetics and Thermodynamics of Ultrasound-Assisted Depolymerization of κ-Carrageenan Ratnawati Ratnawati; Aji Prasetyaningrum; Dyah Hesti Wardhani
Bulletin of Chemical Reaction Engineering & Catalysis 2016: BCREC Volume 11 Issue 1 Year 2016 (April 2016)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.11.1.415.48-58

Abstract

The ultrasound-assisted depolymerization of κ-carrageenan has been studied at various temperatures and times. The κ-carrageenan with initial molecular weight of 545 kDa was dispersed in water to form a 5 g/L solution, which was then depolymerized in an ultrasound device at various temperatures and times. The viscosity of the solution was measured using Brookfield viscometer, which was then used to find the number-average molecular weight by Mark-Houwink equation. To obtain the kinetics of κ-carrageenan depolymerization, the number-average molecular weight data was treated using midpoint-chain scission kinetics model. The pre-exponential factor and activation energies for the reaction are 2.683×10-7 mol g-1 min-1 and 6.43 kJ mol-1, respectively. The limiting molecular weight varies from 160 kDa to 240 kDa, and it is linearly correlated to temperature. The results are compared to the result of thermal depolymerization by calculating the half life. It is revealed that ultrasound assisted depolymerization of κ-carrageenan is faster than thermal depolymerization at temperatures below 72.2°C. Compared to thermal depolymerization, the ultrasound-assisted process has lower values of Ea, ΔG‡, ΔH‡, and ΔS‡, which can be attributed to the ultrasonically induced breakage of non-covalent bonds in κ-carrageenan molecules. 
Co-Authors . Widayat Aat Zaki Mubarok Al Farrel A. Raemas Alwi Meidianto Andri Cahyo Kumoro Bakti Jos Denni Kartika Sari Dessy Ariyanti Dessy Ariyanti Diah Susetyo Retnowati Dyah Arum Kusumaningtyas Dyah Hesti Wardhani Fadlillah Fani Fatoni Nugroho Fauzia Dara Qonita Fitri Lafifa Gian Restu Prinanda Indrawati Dwi Paramita Inggrid K. Wardhani M. Djaeni Muqsit Bramantiya Nadia Sevi Ardiana Nita Aryanti Noer Abyor Handayani Novianto D K Nur Rokhati Nurfiningsih Nurfiningsih Nurul Asiah Pajar Saputra Purbo Suseno Ratnawati Ratnawati Ressa Puspita Dewi Sadam Arrois Samir Badres Teguh Riyanto Widayat Widayat Y. Dinarianasari Yudhy Dharmawan