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MODIFIED STARCH OF AMORPHOPHALLUSCAMPANULATUS AS A NOVEL ADSORBENT FOR WATERADSORPTION Ajeng Yulianti Dwi Lestari; Mohamad Djaeni; Ahmad M Fuadi
Reaktor Volume 16 No.1 Maret 2016
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (751.28 KB) | DOI: 10.14710/reaktor.16.1.9-22

Abstract

A novel adsorbent manufactured from Amorphophallus campanulatus (Porang or Suweg or Elephant Foot Yam or Foot Yam) starch and employed to adsorb water from wet air. The experiment focused on the adding of sodium hydroxide in various concentration of sodium hydroxide (10:1, 10:2.5, 10:5 10:10, 10:20, 10:30, 10:40 mmol/mmol) and its effect to form the new adsorbents shape and chemical bonds. Experimental data were also fitted with several models of isotherm adsorption and adsorption kinetics.Analysis with FTIR and SEM showed that sampel C7 (modified starch with NaOH 40:10 mol) is the adsorbent that could adsorp more water from air and also proofed that foot yam starch can be feasible to be synthesize as an adsorbent for water adsorption.The results also showed that this novel adsorbent fitted with pseudo second order kinetic model and Freundlich isotherm model with maximum adsorption capacity calculated 2.006 g water/g adsorbent.   Keywords: elephant foot yam; starch; sodium hydroxide; water adsorption Abstrak PATI UMBI AMORPHOPHALLUS CAMPANULATUS TERMODIFIKASI SEBAGAI ADSORBEN BARU UNTUK ADSORPSI AIR.Adsorben baru berhasil dibentuk dari pati umbi Amorphophallus campanulatus (Porang atau Suweg) yang kemudian digunakan untuk mengadsorp air dari udara lembab. Penelitian berfokus kepada pengaruh penambahan variasi konsentrasi dari natrium hidroksida (NaOH) (10:1, 10:2,5, 10:5, 10:10, 10:20, 10:30, 10:40 mmol pati/mmol NaOH) atas pembentukan morfologi serta ikatan kimia dari adsorben baru. Data eksperimen kemudian dicocokkan dengan beberapa model isoterm serta kinetika adsorpsi. Analisis dengan menggunakan FTIR dan SEM menunjukkan bahwa sampel C7 (perbandingan pati modifikasi dengan NaOH 40:10 mol) adalah adsorben yang dapat menjerab air lebih banyak dibandingkan dengan adsorben yang lainnya. Hal ini menunjukkan bahwa adsorben dapat menjerab air dari udara lembab dan membuktikan bahwa umbi porang ini layak untuk dijadikan sebuah sumber adsorben alami yang baru. Hasil juga menunjukkan bahwa data eksperimen menunjukkan kesesuaian dengan model kinetika semu orde dua dan model isoterm Freundlich dengan kapasitas adsorpsi maksimal 2,006 g air/g adsorben Kata kunci: umbi Suweg; pati; NaOH; adsorpsi air
PENGARUH PENGERINGAN DENGAN METODE GELEMBUNG TERHADAP SIFAT FISIK PRODUK EKSTRAK BUNGA ROSELA Mohamad Djaeni; Meilya Suzan Triyastuti; Hadiono Soegeng Rahardjo
Reaktor Volume 16 No. 2 Juni 2016
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (593.973 KB) | DOI: 10.14710/reaktor.16.2.96-102

Abstract

Bunga rosela mengandung senyawa antosianin berwarna merah yang kaya antioksidan. Senyawa ini dapat diekstrak dan dikemas dalam bentuk serbuk kering sebagai bahan pewarna makanan dan minuman. Produksi serbuk ekstrak bunga rosela dengan pengeringan konvensional masih menghadapi kendala karena sifatnya yang tidak tahan panas. Penelitian ini bertujuan untuk mempelajari pengaruh pengeringan dengan metode gelembung terhadap sifat fisik ekstrak bunga rosela. Pada proses ini, bunga rosela diekstrak dengan air pada perbandingan 1:10 pada suhu 50oC selama 1 jam. Filtrat yang kaya antosianin dicampur dengan bahan pembentuk gelembung (putih telur) dan penstabil yaitu gliserol mono stearat (GMS). Campuran ini kemudian dikeringkan dengan udara pada temperatur yang berbeda. Dibandingkan dengan pengeringan ekstrak roselle tanpa gelembung, adanya putih telur dan GMS  mampu mempercepat proses penguapan air dari ekstrak yang dikeringkan. Penguapan menjadi lebih cepat pada suhu yang lebih tinggi. Namun demikian, dari penampakan fisik terlihat bahwa pada suhu diatas 70oC, warna ekstrak mulai kehitam-hitaman (akibat karbonasi), serta serbuk yang dihasilkan lebih rapuh
PADDY DRYING IN MIXED ADSORPTION DRYER WITH ZEOLITE: DRYING RATE AND TIME ESTIMATION Mochammad Djaeni; Dewi Ayuningtyas; Nurul Asiah; Hargono Hargono; Ratnawati Ratnawati; Wiratno Wiratno; Jumali Jumali
Reaktor Volume 14, No. 3, APRIL 2013
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (201.999 KB) | DOI: 10.14710/reaktor.14.3.173-178

Abstract

Recently, the main problem of the rice stock and distribution in Indonesia is the quality degradation as indicated in unpleasant odor (smelly), stained, yellowness, and high percentage of broken rice. This is due to the low of paddy quality dried by from either direct sunlight or conventional fluidized bed dryer. As a result, the paddy cracks and breaks easily during milling in which causes the storage life being shorter as the enzymatic degradation by germ or fungi occurs. Air dehumidified with zeolite at drying medium temperature is potential to improve the quality of paddy. Zeolite is a material having high affinity to water vapor. In this case, the paddy and zeolite was mixed and fluidized with the air. The air will evaporate water from paddy, and at same time, the zeolite will adsorb water from air. Hence, the humidity of dryer can be kept low in which improves the driving force for drying. This work discusses the effect of presence of zeolite in the dryer, operational drying temperature, air velocity and relative humidity on drying rate of paddy. The results showed that increasing of zeolite as well as operational temperature increased the drying rate. In addition, using the model, the air dehumidification with zeolite and increase of air velocity can speed up drying time significantly at operational temperature below 80oC. This condition is very suitable for paddy drying since the quality degradation can be avoided.
AKTIVASI ZEOLIT ALAM SEBAGAI ADSORBEN PADA ALAT PENGERING BERSUHU RENDAH Laeli Kurniasari; Mohammad Djaeni; Aprilina Purbasari
Reaktor Volume 13, Nomor 3, Juni 2011
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (588.321 KB) | DOI: 10.14710/reaktor.13.3.178-184

Abstract

ACTIVATION OF NATURAL ZEOLITE AS AN ADSORBENT FOR LOW TEMPERATURE DRYING SYSTEM. Drying is one process which is used in many industries, especially in food product. The process usually still has low energy efficiency and can make food deterioration because of the usage of high temperature. One alternative in drying technology is the use of zeolite as a water vapor adsorbent. This kind of drying method make it possible to operate in lower temperature, hence it will be suitable for heat sensitive product. Natural zeolit can be one promising adsorbent since it is spreadly abundant in Indonesia. Natural zeolite must be activated first before used, in order to get zeolite with high adsorption capacity. Activation process in natural zeolite will change the Si/Al ratio, polarity, and affinity of zeolite toward water vapor and also increase the porosity. Activation of natural zeolite can be done with two methods, chemical activation use NaOH and physical activation use heat. In the activation using NaOH, natural zeolite is immersed with NaOH solution 0.5-2N in 2 hour with temperature range 60-900C. The process is continued with the drying of zeolite in oven with 1100C for 4 hours. While in heat treatment, zeolit is heated into 200-5000C in furnace for 2-5 hours. SEM analysis is used to compare the change in zeolite morphology before and after each treatment, while to know the adsorption capacity of zeolite, the analyses were done in many temperature and relative humidity. Result gives the best condition in NaOH activation is NaOH 1N and temperature 700C, with water vapor loading is 0.171 gr/gr adsorbent. In heat treatment, the best condition is 3000C and 3 hours with loading 0.137 gr water vapor/gr adsorbent.  Pengeringan merupakan salah satu proses yang banyak digunakan pada produk pangan. Proses ini umumnya menyebabkan kerusakan pada bahan pangan, disamping masih rendahnya efisiensi energi. Salah satu alternatif pada proses pengeringan yaitu penggunaan zeolit sebagai adsorben uap air. Proses pengeringan dengan menggunakan zeolit sebagai adsorben ini memungkinkan operasi pengeringan dilakukan pada suhu rendah sehingga sesuai untuk bahan yang tidak tahan panas. Zeolit alam merupakan salah satu alternatif bahan adsorben. Akan tetapi zeolit ini harus diaktivasi terlebih dahulu untuk mendapatkan zeolit dengan kemampuan adsorpsi yang tinggi. Proses aktivasi pada zeolit akan merubah rasio Si/Al zeolit, polaritas serta afinitas zeolit terhadap air dan meningkatkan pori-pori zeolit Adsorpsi zeolit alam dilakukan dengan dua cara yaitu dengan NaOH dan dengan panas. Pada aktivasi dengan NaOH, zeolit dicampur dengan NaOH 0,5-2N selama 2 jam pada suhu 60-900C. Sementara pada aktivasi fisis, zeolit dipanaskan pada 200-5000C selama 2-5 jam. Untuk mengetahui perubahan struktur pori zeolit maka dilakukan analisa SEM dan untuk mengetahui kemampuan adsorpsi zeolit maka dilakukan analisa daya adsorpsi zeolit terhadap uap air pada berbagai suhu dan berbagai kelembaban relatif. Hasil menujukkan bahwa pada aktivasi dengan NaOH diperoleh kondisi aktivasi terbaik adalah NaOH 1N pada pemanasan 700C dengan daya adsorpsi 0,171 gr uap air/gr adsorben. Sementara untuk aktivasi dengan panas, kondisi aktivasi terbaik adalah pemanasan 3000C selama 3 jam dengan daya adsorpsi 0,137 gr uap air/gr adsorben.
KARAKTERISASI PROSES PENGERINGAN JAGUNG DENGAN METODE MIXED-ADSORPTION DRYING MENGGUNAKAN ZEOLITE PADA UNGGUN TERFLUIDISASI Hargono Hargono; Mohamad Djaeni; Luqman Buchori
Reaktor Volume 14, Nomor 1, April 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (322.265 KB) | DOI: 10.14710/reaktor.14.1.33-38

Abstract

CHARACTERIZATION OF CORN DRYING PROCESS USING MIXED-ADSORPTION DRYING METHOD UTILIZING ZEOLITE PARTICLES IN A FLUIDIZED BED SYSTEM. Corn (Zea mays L.) representing important food requirement besides paddy and wheat. Handling of time after rice harvest become the priority so that corn quality can be awaked better. Drying process by adsorption-fluidized bed become a choice to replace the conventional corn drying systems. This research aim to look for the effect of the inlet air temperature, type of zeolite, and ratio of corn and zeolite to drying rate, content of protein and fat, and to calculate dying rate constant, k. Energy efficiency is calculated based on amount of heat is used to evaporate the water from corn (Qevap) divided by total of heat requirement for the regeneration of zeolite and increase the air temperature (Qintr). This research conducted by mixing zeolite as adsorben with the corn with the certain comparison ratio in the fluidized bed at temperature of 30-50oC. Results of research indicate that the fastest drying rate is marked by biggest water rate degradation that happened at 50oC by zeolite sintetis and ratio of corn and zeolite is 25:75%. Drying rate constant is 0.0303. Protein content degradates from 9.10% to 8.30%, while for the content of fat is constant. Energy efficiency is obtained of 81.23%. Jagung (Zea mays L.) merupakan kebutuhan pangan yang penting selain padi dan gandum sehingga penanganan paska panen menjadi prioritas agar kualitas jagung dapat terjaga dengan baik. Proses pengeringan dengan cara adsorpsi-unggun terfluidisasi menjadi suatu pilihan untuk menggantikan sistim pengering jagung konvensional yang boros energi. Penelitian ini bertujuan untuk mencari pengaruh suhu udara masuk, jenis zeolite, dan rasio berat jagung dan zeolite terhadap kecepatan pengeringan, kandungan protein dan lemak dan menghitung harga konstanta laju pengeringan, k. Untuk keperluan energi dihitung pula efisiensi energi (h) berdasarkan jumlah panas yang digunakan untuk menguapkan air dari jagung (Qevap) dibagi dengan kebutuhan panas total untuk meregenerasi zeolite dan menaikkan suhu udara (Qintr). Penelitian dilakukan dengan mencampurkan zeolite sebagai adsorben dengan jagung dengan rasio perbandingan tertentu dalam suatu unggun yang difluidisasi menggunakan udara pada suhu percobaan 30-50oC. Hasil penelitian menunjukkan bahwa laju pengeringan paling cepat ditandai oleh penurunan kadar air yang paling besar yang terjadi pada suhu 50oC dengan menggunakan zeolite sintetis dan dengan rasio berat jagung dan zeolite adalah 25% : 75%. Nilai konstanta laju pengeringan diperoleh 0,0303. Kadar protein terjadi penurunan dari 9,10% menjadi 8,30%, sedangkan untuk kandungan lemaknya relatif tetap. Hasil perhitungan diperoleh efisiensi energi (h) sebesar 81,23%.
UPAYA PENINGKATAN MUTU DAN EFISIENSI PROSES PENGERINGAN JAGUNG DENGAN MIXED-ADSORPTION DRYER Luqman Buchori; Mohamad Djaeni; Laeli Kurniasari
Reaktor Volume 14, No. 3, APRIL 2013
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (420.285 KB) | DOI: 10.14710/reaktor.14.3.193-198

Abstract

THE EFFORT OF EFFICIENCY AND QUALITY IMPROVEMENT ON CORN DRYING PROCESS USING MIXED-ADSORPTION DRYER. The main problem in corn drying process is the low of energy efficiency (50%) and quality products. Consequently, operating costs in large for fuel consumption and the short shelf life of corn. Zeolite adsorption dryers have the potential to overcome this problem. This research aims to study composition of corn-zeolite and the effect of temperature on drying speed and protein and fat content in corn. Research variables are the ratio of corn and zeolite (1:0, 1:3, 1:1, 3:1) and intake air temperature (room temperature, 30oC, 40oC, 50oC). Sampling for moisture testing performed every 15 minutes. For energy purposes also calculated the energy efficiency (h) based on the amount of heat used to evaporate water from the corn (Qevap) divided by the total heat requirement to regenerate the zeolite and raising the air temperature (Qintr). Profiles of temperature and water in the mixed adsorption dryer are also studied. The results showed that the greater number of zeolite used, the water content of the final outcome a little more drying, protein and fat content of the final result of drying is relatively constant. The larger intake air temperature, the water content of the less drying results, protein content decreases, and the fat content does not change/relatively constant. The best variable was a ratio of corn: zeolite is 1:3 and air temperature was 50oC. While the variables that are suitable and in accordance with ISO standards for dry foods (14%) are air temperature of between 40oC and 50oC with a ratio of corn:zeolite is 1:3. The energy efficiency of 81.23% is obtained. Modeling done with FEMLAB (COMSOL) can describe the moisture content and temperature profiles in the corn and zeolite. Keywords: corn; drying; energy efficiency; mixed adsorption dryer; zeolite Abstrak Masalah utama proses pengeringan jagung adalah rendahnya efisiensi energi (50%) dan mutu produk sehingga beban biaya operasi besar untuk konsumsi bahan bakar. Pengering adsorpsi dengan zeolite berpotensi untuk mengatasi permasalahan ini. Penelitian ini bertujuan untuk mempelajari pengaruh komposisi jagung-zeolite dan suhu terhadap kecepatan pengeringan dan kandungan protein dan lemak di dalam jagung. Penelitian dilakukan dengan variabel berubah yaitu rasio antara jagung dan zeolit (1:0, 1:3, 1:1, 3:1) dan suhu udara masuk (suhu kamar, 30oC, 40oC, 50oC). Pengambilan sampel untuk pengujian kadar air dilakukan setiap 15 menit. Untuk keperluan energi dihitung pula efisiensi energi (h) berdasarkan jumlah panas yang digunakan untuk menguapkan air dari jagung (Qevap) dibagi dengan kebutuhan panas total untuk meregenerasi zeolit dan menaikkan suhu udara (Qintr). Profil temperatur dan air di dalam mixed adsorption dryer juga dipelajari. Hasil penelitian menunjukkan bahwa semakin banyak jumlah zeolit yang digunakan, kadar air hasil akhir pengeringan makin sedikit, kadar protein dan lemak hasil akhir pengeringan relatif konstan. Semakin besar suhu udara masuk pengering, kadar air hasil pengeringan makin sedikit, kadar protein semakin menurun, dan kadar lemak tidak berubah/relatif konstan. Variabel yang terbaik adalah variabel dengan rasio jagung:zeolit yaitu 1:3 dan menggunakan suhu udara pengering 50oC. Sedangkan variabel yang cocok dan sesuai dengan standar SNI untuk makanan kering (14%) adalah variabel dengan menggunakan suhu udara pengering antara 40oC dan 50oC dengan rasio berat jagung : zeolit adalah 1:3. Efisiensi energi diperoleh sebesar 81,23%. Pemodelan yang dilakukan dengan Femlab (COMSOL) dapat menggambarkan profil kandungan air dan suhu di dalam jagung dan zeolit. Kata kunci : jagung; pengeringan; efisiensi energi; mixed adsorption dryer; zeolit
DRYING TIME ESTIMATION OF CARRAGEENAN-EGG WHITE MIXTURE AT TRAY DRYER Mohamad Djaeni; Aji Prasetyaningrum; Nurul Asiah; Ratnawati Hartono
International Journal of Science and Engineering Vol 6, No 2 (2014)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (801.327 KB) | DOI: 10.12777/ijse.6.2.122-125

Abstract

The drying is the last step to find carrageenan product. Currently, the carrageenan drying still deals with too long drying time. This because, during the process carrageenan and water forms gel stucture in which hampers the water diffusion to the surface. Foaming agent introduction such as egg white can be considered to break the gel structure and make the drying process being smooth and fast. This paper discusses the effect of egg white as foaming agent on the drying time of carrageenan. In this study, the carrageenan was mixed with egg white to form foam that can break the gel and create the pore for improving the surface area.  The carrageenan and egg white mixture was then dried at different air temperature and humidity. Results showed that the drying time was shortened with the presence of egg whiet as well as the increase of air temperature. For example, the drying time at air temperature 80oC with  20 % egg white was about 60 minutes shorter than that of without foam. In addition, the lowering air dehumidification affected the drying time positively.
Preparation of Natural Zeolite for Air Dehumidification in Food Drying Mohamad Djaeni; Laeli Laeli Kurniasari; Setia Budi Sasongko
International Journal of Science and Engineering Vol 8, No 2 (2015)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (182.262 KB) | DOI: 10.12777/ijse.8.2.80-83

Abstract

Drying with air dehumidification with solid adsorbent improves the quality of food product as well as energy efficiency. The natural zeolite is one of adsorbent having potential to adsorb the water.  Normally, the material was activated to open the pore, remove the organic impurities, and increase Si/Al rate. Hence, it can enhance the adsorbing capacity. This research studied the activation of natural zeolite mined from Klaten, Indonesia as air dehumidification for food drying. Two different methods were used involving activation by heat and NaOH introduction.  As indicators, the porosity and water loaded were evaluated. Results showed both methods improved the adsorbing capacity significantly. With NaOH, the adsorbing capacity was higher. The simple test in onion and corn drying showed the presence of activated natural zeolite can speed up water evaporation positively. This performance was also comparable with Zeolite 3A
Drying Spirulina with Foam Mat Drying at Medium Temperature Aji Prasetyaningrum; Mohamad Djaeni
International Journal of Science and Engineering Vol 3, No 2 (2012)
Publisher : Chemical Engineering Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (745.186 KB) | DOI: 10.12777/ijse.3.2.1-3

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Spirulina is a single cell blue green microalgae (Cyanobacteria) containing many Phytonutrients (Beta-carotene, Chlorophyl, Xanthophyl, Phyocianin) using as anti-carcinogen in food. Producing dry spirulina by quick drying process at medium temperature is very important to retain the Phytonutrient quality. Currently, the work is still challenging due to the gel formation that block the water diffusion from inside to the surface.  This research studies the performance of foam-mat drying on production of dry spirulina. In this method the spirulina was mixed with foaming agent (glair/egg albumen, popular as white egg) at 2.5% by weight at air velocity 2.2 m/sec. Here, the effect of spirulina thickness and operational temperature on drying time and quality (Beta-carotene and color) were observed. The drying time was estimated based on the measurement of water content in spirulina versus time. Result showed that the thicker spirulina, the longer drying time. Conversely, the higher operational temperature, faster drying time. At thickness ranging 1-3 mm and operational temperature below 70oC, the quality of spirulina can fit the market requirement
PENGERINGAN JAGUNG DENGAN METODE MIXED-ADSORPTION DRYING MENGGUNAKAN ZEOLITE PADA UNGGUN TERFLUIDISASI M Djaeni; A. Agusniar; D. Setyani; Hargono .
Prosiding SNST Fakultas Teknik Vol 1, No 1 (2011): PROSIDING SEMINAR NASIONAL SAINS DAN TEKNOLOGI 2 2011
Publisher : Prosiding SNST Fakultas Teknik

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

Abstract

Jagung (Zea mays L.) merupakan salah satu tanaman yang penting, sebagai sumber makanan dan obat. Penanganan pasca panen jagung yaitu pengeringan sangat menentukan kualitas jagung untuk penggunaan selanjutnya. Proses pengeringan dengan cara adsorpsi menjadi suatu pilihan untuk menggantikan sistim pengering jagung konvensional. Penelitian ini bertujuan untuk mengetahui pengaruh suhu udara masuk, jenis zeolite, dan rasio berat jagung dan zeolite terhadap kecepatan pengeringan dan menghitung harga konstanta laju pengeringan. Pada penelitian ini, zeolite sebagai adsorben dicampur dengan jagung dengan rasio perbandingan tertentu dalam suatu unggun, kemudian difluidisasi dengan udara dengan suhu 30oC-50oC.  Udara akan menguapkan air dari jagung, dan pada saat yang sama, zeolite akan menyerap air dari udara ini, sehingga kelembaban udara akan terjaga rendah. Hasil penelitian menunjukkan bahwa laju pengeringan paling cepat ditandai oleh penurunan kadar air yang paling besar, yang terjadi pada suhu 50oC, dengan menggunakan zeolite sintetis, dan dengan rasio berat jagung dan zeolite adalah 25% : 75%. Harga konstanta laju pengeringan pada variabel ini adalah 0,0303. Hasil menunjukkan bahwa semakin meningkatnya suhu udara pengering maka penurunan kadar air semakin besar sehingga laju pengeringan semakin cepat. Kata kunci: adsorpsi; jagung; pengeringan; zeolite.