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All Journal International Journal of Advances in Applied Sciences Reaktor Prosiding Seminar Nasional Sains Dan Teknologi Fakultas Teknik Journal Of Chemical Process Engineering (JCPE) Abdimas Umtas : Jurnal Pengabdian kepada Masyarakat Abdimas: Jurnal Pengabdian Masyarakat Universitas Merdeka Malang REACTOR : Journal of Research On Chemistry And Engineering

Megawati Megawati

D3 Teknik Kimia, Fakultas Teknik, Universitas Negeri Semarang Gedung E1, Kampus Sekaran, Gunung Pati, Semarang 50229

Author-ID : 2956418

Religion Aerospace Engineering Agriculture, Biological Sciences & Forestry Arts Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Control & Systems Engineering Earth & Planetary Sciences Education Energy Engineering Environmental Science Materials Science & Nanotechnology Mathematics Physics Social Sciences

Published : 9 Documents Claim Missing Document

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Articles

The Kinetics of Calcium Oxide Catalyzed Esterification of Glycerol with Free Fatty Acids Using Pseudo-homogeneous Model Approach Megawati Megawati; Dhoni Hartanto; Catur Rini Widyastuti; Diyah Saras Wati; Eny Nurhayati
Reaktor Volume 18 No. 1 March 2018
Publisher : Dept. of Chemical Engineering, Diponegoro University

Abstract This research aims to study the reaction kinetics of esterification reaction of glycerol with free fatty acid (FFA) using calcium oxide catalyst to produce mono-diacylglycerol (MDAG) using pseudo-homogeneous approach. The effects of time and temperature on the reaction conversion were investigated simultaneously. The FFA used was from the waste of cocoa production process, while the solid catalyst used was calcium oxide from eggshell ash. The results show that the cocoa based FFA was composed of palmitic acid (49.24%), methyl stearate (1.05%), oleic acid (25.39%), and stearic acid (24.32%). The calcium oxide content in the eggshell ash was 60% w/w. At all temperatures studied (60, 70, and 80oC), as the reaction time increased, the conversion increased sharply in the first 5 minute followed by a gradual raise to an almost constant value after 20 minutes (0.844; 0.845; and 0.854, respectively). Pseudo-homogeneous second order model can describe the reaction kinetics satisfactorily. The reaction constants (k) at 60, 70, and 80oC were 0.00384, 0.003401, and 0.003518 (L/mole.minute), respectively. The effects of temperature on reaction rate obey the Arrhenius’ equation with collision factor (A) is 0.2659 (L/mole.minute) and activation energy (Ea) is 3544 J/mol. Keywords: calcium oxide; free fatty acid; glycerol; pseudo-homogeneous approach

KINETIKA REAKSI HIDROLISIS Megawati Megawati; Wahyudi Budi Sediawan; Hary Sulistyo; Muslikhin Hidayat
Reaktor Volume 12, Nomor 4, Desember 2009
Publisher : Dept. of Chemical Engineering, Diponegoro University

Bio-etanol merupakan salah satu bahan bakar organik yang dapat diproduksi dari pati dan selulosa. Bahan berbasis selulosa dapat ditemukan dalam limbah organik, diantaranya: grajen kayu, ranting kering, daun kering, tongkol jagung, sekam padi dan lain-lain. Langkah-langkah penting pada produksi etanol dari lignoselulosa ialah hidrolisis untuk mengkonversi hemiselulosa dan selulosa menjadi gula, fermentasi gula untuk memproduksi etanol, dan pemurnian etanol. Penelitian ini mempelajari reaksi hidrolisis ranting kering dengan asam encer pada kondisi non-isotermis. Dua ratus gram ranting kering dicampur dengan 1200 cm3 larutan asam sulfat 0,18 N dan dipanaskan di dalam autoklaf. Selama proses hidrolisis ini, suhu akan terus naik (non-isotermis), kemudian setelah mencapai suhu tertentu dijaga tetap (suhu akhir). Hasil hidrolisis pertama diambil pada suhu 413 K dan seterusnya diambil setiap interval 5 menit. Suhu akhir divariasi pada 433 K, 453 K, 473 K dan 493 K. Metode Fehling dipilih untuk menganalisis kandungan gula di dalam sampel. Persamaan kinetika reaksi diperoleh dengan mengolah data dengan pendekatan model shrinking-core dengan ukuran partikel tetap. Nilai tetapan kecepatan reaksi meningkat sedangkan nilai tetapan transfer massa relatif tidak berubah pada berbagai suhu. Tetapan kecepatan reaksi dapat didekati dengan persamaan Arrhenius, dengan frekuensi tumbukan Ar = 0,083 l/(mol.menit) dan energi aktivasi Er = 20.000 J/mol. Untuk menyelidiki langkah mana yang mengontrol laju proses, dibandingkan tetapan kecepatan reaksi dan tetapan transfer massa pada 493 K, diperoleh nilai tetapan transfer massa berkisar 0,06 l/(mol.menit), dan nilai tetapan kecepatan reaksi berkisar 0,00051 l/(mol.menit), sehingga diperoleh bilangan Hatta 0,00933. Karena bilangan Hatta < 0,02 maka dapat disimpulkan bahwa reaksi kimia lebih mengontrol daripada transfer massa.

Kinetics of Enzymatic Hydrolysis of Passion Fruit Peel using Cellulase in Bio-ethanol Production Megawati Megawati; Astrilia Damayanti; Radenrara Putri; Angga Pratama; Tsani Muftidar
Reaktor Volume 20 No.1 March 2020
Publisher : Dept. of Chemical Engineering, Diponegoro University

This research aims to study the hydrolysis of passion fruit peel using cellulase and its evaluation for ethanol production. Passion fruit peel is a fruit processing waste that has not been utilized properly. Passion fruit peel contains holo-cellulose (64% w/w), which can be converted into ethanol through hydrolysis followed by fermentation. Hydrolysis using cellulase is more efficient and its fermentation using yeast to produce ethanol is common. The hydrolysis is carried out at various enzyme ratios (3, 5, 7, and 9% v/v) and at temperature 30 oC, material concentration 5 g/100 mL, pH 4-5, and shaking speed 160 rpm. The kinetics chosen were heterogeneous models; they were the fractal model by Valjamae and Kopelman. Before being hydrolyzed, the essential oil and pectin in passion fruit peel were extracted, because the compositions were quite high; the results were around 16.23 and 11.36% w/w, respectively. The effect of the enzyme ratio to the sugar concentration by hydrolysis is very significant. At 9 h, the glucose concentration reached 45.38, 51.86, 60.50, 66.00 g/L at various enzyme ratios of 3, 5, 7, 9% v/v. During the hydrolysis, the glucose concentration continues to increase and starts to decrease after 9 h. Hydrolyzate solution fermentation obtained from hydrolysis in various enzyme ratios showed consistent results; the higher the enzyme ratio and glucose, and the higher the ethanol will be (5.6, 6.8, 7.6, and 8.9% v/v). The kinetics model by Valjamae is more appropriate to describe the enzymatic hydrolysis mechanism of passion fruit peel than Kopelman. The fractal exponent values obtained from Valjamae and Kopelman models were 0.28 and 0.27. In Valjamae model, the enzyme ratio rises, from 3 to 9% v/v, the rate constant rises from 0.22 to 0.53 1/h. In Kopelman model, the rate constant rises too, from 0.21 to 0.51 1/h.Keywords: bio-ethanol; cellulase; enzymatic hydrolysis; fractal kinetic; passion fruit peel

PEMBUATAN ETANOL DARI LIMBAH KULIT JERUK BALI: HIDROLISIS MENGGUNAKAN SELULASE DAN FERMENTASI DENGAN YEAST Megawati Megawati; Ratih Ciptasari
Prosiding SNST Fakultas Teknik Vol 1, No 1 (2015): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 6 2015
Publisher : Prosiding SNST Fakultas Teknik

Show Abstract | Download Original | Original Source | Check in Google Scholar

Penelitian ini dilakukan untuk mengetahui proses pembuatan etanol dari limbah kulit jeruk bali, pengaruh penambahan enzim terhadap konsentrasi gula reduksi, dan kadar etanol yang dihasilkan. Pada penelitian ini, selulosa dalam kulit jeruk bali dihidrolisis secara enzimatis menggunakan enzim selulase dengan variasi penambahan volum enzim, yaitu 3, 5, 7, dan 9 mL. Konsentrasi gula dalam hidrolisat diuji dengan metode titrasi Fehling. Setelah itu, hidrolisat difermentasi menggunakan Saccharomyses cerevisiae selama 5 hari. Larutan bioetanol hasil fermentasi dipisahkan dari residunya, kemudian etanol dipisahkan dari larutan dengan distilasi.Hasil penelitian menunjukkan bahwa etanol dapat dihasilkan dari limbah kulit jeruk bali melalui proses hidrolisis, fermentasi, dan distilasi. Semakin banyak katalis enzim yang ditambahkan maka semakin tinggi konsentrasi gula hasil hidrolisis dan semakin besar kadar etanol yang terbentuk sebagai hasil fermentasi. Konsentrasi gula maksimal yang diperoleh sebesar 0,016 mol/L pada variasi penambahan enzim 9 mL dan kadar etanol optimumnya sebesar 40,30%, dengan densitas etanol 0,95 g/mL. Kata Kunci: etanol, fermentasi dengan yeast, hidrolisis dengan enzim, kulit jeruk

Pengaruh Perbedaan Pelarut Asam Pada Ekstraksi Antosianin Bunga Dadap Merah (Erythrina Crista-Galli) Dengan Metode Microwave Assisted Extraction astrilia damayanti; Megawati Megawati; Nur Kholifah Chandra Mulyani; Eva Amalia Alvionita
Journal of Chemical Process Engineering Vol 5, No 1 (2020)
Publisher : Universitas Muslim Indonesia

Penggunaan pewarna alami pada berbagai bidang teknologi sekarang ini dapat menggunakan tanaman karena dapat diperbaharui, bunga dadap merah menjadi salah satu sumber pigmen antosianin yang banyak ditemukan di Indonesia. Penelitian ini bertujuan untuk menentukan pelarut asam terbaik dalam proses ekstraksi ditinjau dari kadar total antosianinnya. Proses ekstraksi dadap merah dilakukan dengan metode gelombang mikro menggunakan microwave. Daya microwave yang digunakan sebesar 600 W. Ekstraksi antosianin dilakukan dengan perbedaan pelarut yaitu etanol yang diasamkan menggunakan 4% asam sitrat, 4% asam tartarat dan 1% HCl. Rasio pelarut yang digunakan sebesar 1:25 dan waktu selama 3, 6, 9, 12 dan 15 menit. Kadar antosianin tertinggi yang diperoleh masing-masing pelarut dilakukan uji karakteristik intensitas warnanya. Hasil ekstraksi antosianin tertinggi menggunakan 4% asam sitrat diperoleh sebesar 3,673754647 mg/L pada waktu 12 menit. Antosianin tertinggi menggunakan 4% asam tartarat diperoleh sebesar 8,098959108 mg/L pada waktu 3 menit. Antosianin tertinggi yang diperoleh menggunakan 1% HCl sebesar 28,52169517 mg/L pada waktu ekstraksi 12 menit. Intensitas warna antosianin tertinggi diperoleh pada pelarut etanol yang diasamkan menggunakan 1% HCl. Hasil penelitian ini menunjukkan bahwa ekstraksi antosianin terbaik adalah ekstraksi menggunakan pelarut etanol yang diasamkan dengan 1% HCl.

Peningkatan Nilai Tambah Biji Durian (Durio Zibethinus) Dan Biji Rambutan (Nephelium Lappaceum) Menjadi Keripik Astrilia Damayanti; Riana Defi Mahadji Putri; Megawati Megawati; Desy Hikmatul Siami; Zulfi Fitriani
ABDIMAS: Jurnal Pengabdian Masyarakat Vol. 3 No. 2 (2020): ABDIMAS UMTAS: Jurnal Pengabdian Kepada Masyarakat
Publisher : LPPM Universitas Muhammadiyah Tasikmalaya

Tujuan kegiatan ini adalah untuk memperkenalkan teknologi pangan kepada ibu-ibu PKK RT03/RW03, Kelurahan Ngijo, Kecamatan Gunungpati, Semarang dengan memanfaatkan biji Durian (Durio zibethinus) dan biji Rambutan (Nephelium lappaceum) sebagai keripik. Target luaran yang diharapkan antara lain masyarakat dapat berwirausaha sehingga kesejahteraan keluarga dapat ditingkatkan. Hasil dari program pengabdian masyarakat yang telah dilakukan ini adalah sebagai berikut: aspek penerapan iptek produk pangan dipandang sangat efektif untuk membangun kemandirian masyarakat yang berbasis potensi lokal yakni pemanfaatan biji durian dan biji rambutan, dan aspek manfaat yang dihasilkan dari program ini sangat besar yaitu meningkatkan kesadaran masyarakat untuk memanfaatkan potensi pohon Durian dan Rambutan terutama bijinya untuk dibuat menjadi keripik, meningkatnya pengetahuan dan keterampilan masyarakat bidang pengolahan biji durian dan rambutan untuk dibuat keripik serta menumbuhkan motivasi berwirausaha khususnya di RT03/RW03, Kelurahan Ngijo, Kecamatan Gunungpati, Semarang.

Hidrolisis Limbah Kulit Pisang (Musa acuminata) Menggunakan Katalis Asam untuk Produksi Bioetanol Zuhriyan Ash shiddieqy Bahlawan; Megawati Megawati; Bayu Triwibowo; Alfiansyah Aji Pratama; Zefanya Pradiza; Anggun Septiamurti
REACTOR: Journal of Research on Chemistry and Engineering Vol 3, No 1 (2022): Published in June 2022
Publisher : Politeknik ATI Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.52759/reactor.v3i1.45

Banana is one of the fruits that can thrive in Indonesia. This plant is often found in tropical soils with slightly moist soil conditions. However, banana peels are underutilized and are only disposed of as agricultural waste. On the other hand, the carbohydrate content of banana peels is still quite high, reaching 12.2% so it can be used as raw material for making bioethanol. Carbohydrates in the substrate cannot be directly converted into bioethanol but need to be pretreated first to break down polysaccharides into monosaccharides. In this research, the pretreatment process of carbohydrate hydrolysis from banana peels into reducing sugars is studied. From the studies, the reducing sugar concentration was obtained with banana peels substrate concentration of 20 g/L, 5 M of sulfuric acid concentration, and an optimum hydrolysis time of 70 minutes with the obtained reducing sugar reach 16.82 g/L. Reducing sugar can be converted into bioethanol by fermentation process with S. cerevisiae yeast. It is hoped that these studies can provide an initial impact on the development of alternative energy based on biomass and utilization of banana peel waste.

An overview of the potential of Citrus hystrix (kaffir lime) essential oil as mosquito repellent Nurul Asyikin Md Zaki; Junaidah Jai; Izzat Syahmi Kamal Shahrizan; Dewi Selvia Fardhyanti; Megawati Megawati; Nadya Alfa Cahaya Imani
International Journal of Advances in Applied Sciences Vol 11, No 4: December 2022
Publisher : Institute of Advanced Engineering and Science

A chemical-based insect repellent such as N, N-diethyl-3-methylbenzamide (DEET) is commonly used against all insects despite its toxicity in humans. Hence, a repellent agent from natural sources of plant essential oil was introduced. Some of the plants which have the repellent potential are catnip, hairy basil, citronella, vetiver, clove, and citrus. Citronellal, citronellol, geraniol, eugenol, eugenol-acetate, and beta-caryophyllene are among the repellent active components in these plants. Citrus hystrix (kaffir lime) was known for several applications in food, health, and skincare, but its potential as mosquito repellent is still new. This overview paper highlights the potential of kaffir lime essential oil as a mosquito repellent and the encapsulation of essential oil related to mosquito repellent. Several studies on kaffir lime essential oil as mosquito repellent was conducted and revealed that the major repellent active components are citronellol and limonene. Pure kaffir lime essential oil provides one-hour repellent protection against the mosquito. However, an addition of 5% vanillin prolongs the protection time to three hours. Essential oil is easily vaporized at room temperature which shortens its effectiveness time. Encapsulation of the essential oil would control the vaporization process and hence prolong its efficiency. Nonetheless, almost no research work reported on the encapsulation of kaffir lime essential oil and the release mechanism of the encapsulated kaffir lime.

Training on making kombucha tea from snake fruit peel and butterfly pea flower Astrilia Damayanti; Megawati Megawati; Widi Astuti; Luluk Arvi Cahyaning Suwandi; Reyhan Dwi Saputra; Melanie Hartalia Putrie
Abdimas: Jurnal Pengabdian Masyarakat Universitas Merdeka Malang Vol 7, No 4 (2022): November 2022
Publisher : University of Merdeka Malang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26905/abdimas.v7i4.8240

Snake fruit peel is an organic waste that is often not utilized, while the flower of the butterfly pea is known as a natural dye for food and beverages. The COVID-19 pandemic causes susceptibility to the human body. Therefore, it is necessary to process healthy drinks in order to utilize organic waste. This community service program activity aims to introduce fermented food processing to the community, especially the Family Welfare Development (PKK) Group RT 3 RW 3, Ngijo Village, Gunungpati District, Semarang City by utilizing snake fruit peel (Salacca zalacca) and butterfly pea flower (Clitoria ternatea) as kombucha tea. The method of this program is in the form of delivering material either through posters, videos, demonstrations, and youtube links. A positive response was given by community after conducting a taste test on the product that was socialized in the form of many questions submitted including other alternative raw materials and the volume of kombucha tea served. This program has the potential to foster community motivation in entrepreneurship so that family income will increase.

Co-Authors Alfiansyah Aji Pratama Angga Pratama Anggun Septiamurti Astrilia Damayanti Bahlawan, Zuhriyan Ash Shiddieqy Bayu Triwibowo Catur Rini Widyastuti, Catur Rini Desy Hikmatul Siami Dewi Selvia Fardhyanti Dhoni Hartanto Diyah Saras Wati Eny Nurhayati Eva Amalia Alvionita Hary Sulistyo Izzat Syahmi Kamal Shahrizan Junaidah Jai Luluk Arvi Cahyaning Suwandi Melanie Hartalia Putrie Muslikhin Hidayat Nadya Alfa Cahaya Imani Nur Kholifah Chandra Mulyani Nurul Asyikin Md Zaki Radenrara Putri Ratih Ciptasari Reyhan Dwi Saputra Riana Defi Mahadji Putri Tsani Muftidar Wahyudi Budi Sediawan Widi Astuti Zefanya Pradiza Zulfi Fitriani

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