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LAYER BY LAYER COMPOSITE MEMBRANES OF ALGINATE-CHITOSAN CROSSLINKED BY GLUTARALDEHYDE IN PERVAPORATION DEHYDRATION OF ETHANOL Rokhati, Nur; Istirokhatun, Titik; Samsudin, Asep Muhamad
International Journal of Renewable Energy Development Vol 5, No 2 (2016): July 2016
Publisher : Center of Biomass & Renewable Energy, Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (802.193 KB) | DOI: 10.14710/ijred.5.2.101-106

Abstract

Hydrophilicity of membrane causing only water can pass through membrane. Pervaporation process using organophilic membrane has been offered as alternative for ethanol dehydration. This paper investigate pervaporation based biopolymer composite membrane from alginate-chitosan using layer by layer method prepared by glutaraldehyde as crosslinking agent and polyethersulfone (PES) as supported membrane. Characterization of crosslinked of composite membrane by FTIR helped in identification of sites for interaction between layers of membrane and support layer (PES). The SEM showed a multilayer structure and a distinct interface between the chitosan layer, the sodium alginate layer and the support layer. The coating sequence of membranes had an obvious influence on the pervaporation dehydration performance of membranes. For the dehydration of 95 wt% ethanol-water mixtures, a good performance of PES-chitosan-alginate-chitosan (PES/Chi/Alg/Chi) composite membrane was found in the pervaporation dehydration of ethanol. Article History: Received April 12nd , 2016; Received in revised form June 25th , 2016; Accepted July 1st , 2016; Available onlineHow to Cite This Article: Rokhati, N., Istirokhatun, T. and Samsudin, A.M. (2016) Layer by Layer Composite Membranes of Alginate-Chitosan Crosslinked by Glutaraldehyde in Pervaporation Dehydration of Ethanol. Int. Journal of Renewable Energy Development, 5(2), 101-106.http://dx.doi.org/10.14710/ijred.5.2.101-106 
Pengaruh Jumlah Kendaraan dan Faktor Meteorologis (Suhu, Kecepatan Angin) Terhadap Peningkatan Konsentrasi Gas Pencemar CO, NO2, dan SO2 Pada Persimpangan Jalan Kota Semarang (Studi Kasus Jalan Karangrejo Raya, Sukun Raya, dan Ngesrep Timur V) Noviani R., Elaeis; Ramayana L. Tobing, Kiki; Tetriana A., Ita; Istirokhatun, Titik
DIPOIPTEKS: Jurnal Ilmiah Mahasiswa Undip DIPOIPTEKS Vol. 1, No. 1 (2013)
Publisher : DIPOIPTEKS: Jurnal Ilmiah Mahasiswa Undip

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (528.202 KB)

Abstract

Jalan Ngesrep Timur V, Jalan Sukun Raya dan Jalan Karangrejo Raya Kota Semarang adalah jalan yang terletak di persimpangan yang terdapat di kecamatan Banyumanik yang merupakan jalan kolektor yaitu jalan yang melayani angkutan pengumpulan atau pembagian dengan ciri-ciri perjalanan sedang, kecepatan rata-rata yang sedang dan jumlah jalan masuk yang dibatasi. Jalan Karangrejo Raya dan jalan Sukun Raya dialokasikan sebagai pusat aktivitas dan aglomerasi penduduk seiring dengan bermunculnya fasilitas perdagangan dan perumahan baru, sedangkan jalan Ngesrep Timur V dialokasikan sebagai fasilitas pendidikan karena adanya 3 perguruan tinggi yang cukup ternama di kawasan ini yaitu Universitas Diponegoro, Politeknik Negeri Semarang dan Politeknik Kesehatan Semarang. Semakin hari jumlah kendaraan yang melintasi Jalan Ngesrep Timur V, Jalan Sukun Raya dan Jalan Karangrejo Raya semakin meningkat, yang dapat mengakibatkan terjadinya pencemaran udara akibat kendaraan bermotor yang lalu lalang di jalan tersebut terutama gas pencemar CO, SO2, dan NO2 yang berasal dari aktivitas kendaraan bermotor. Hal ini menjadi latar belakang untuk diadakannya penelitian guna mengetahui besar konsentrasi gas pencemar di ketiga jalan tersebut.Metode penelitian yang digunakan adalah pengambilan sampel secara langsung di lokasi pada saat jam padat kendaraan yaitu pada pagi hari (07.00-08.00), siang hari (13.00-14.00), dan sore hari (16.00-17.00) selama 12 hari masing-masing 3 hari berturut-turut di Jalan Karangrejo Raya, Jalan Sukun Raya, dan Jalan Ngesrep Timur V dan 3 hari sisanya membandingkan kedua jalan, dimulai dari Jalan Karangrejo Raya dan Sukun Raya, Jalan Karangrejo Raya dan Ngesrep Timur V, dan Jalan Sukun Raya dan Ngesrep Timur V. Berdasarkan hasil penelitian yang telah dianalisa, konsentrasi CO di jalan Karangrejo Raya berkisar antara 8-14ppm, konsentrasi CO di jalan Sukun Raya berkisar 8-17ppm, dan konsentrasi CO di jalan Ngesrep Timur V 8-19ppm. Hal ini menunjukkan konsentrasi CO di ketiga jalan berada di atas baku mutu. Sedangkan konsentrasi NO2 di Jalan Karangrejo Raya berkisar antara 0,7-4,2μg/Nm3, konsentrasi NO2 di Jalan Sukun Raya berkisar antara 1,0-4,1μg/Nm3, dan konsentrasi NO2 di Jalan Ngesrep Timur V berkisar antara 0,2-1,7μg/Nm3. Hal ini menunjukkan bahwa konsentrasi NO2 di ketiga jalan berada jauh dibawah baku mutu. Hasil statistik menunjukkan bahwa jumlah kendaraan dan faktor meteorologis seperti, suhu, kecepatan angin mempengaruhi konsentrasi CO, NO2. Selanjutnya untuk konsentrasi SO2 yang berada di Jalan Karangrejo Raya berkisar 14-21,1 μg/Nm3, untuk Jalan Sukun Raya sebesar 14-18,8 μg/Nm3 dan konsentrasi SO 2 yang terukur di Jalan Ngesrep Timur V yaitu 0,4-6,1 μg/Nm3.
ULTRAFILTRATION AS PRETREATMENT OF REVERSE OSMOSIS: LOW FOULING ULTRAFILTRATION MEMBRANE PREPARED FROM POLYETHERSULFONE–AMPHIPHILIC BLOCK COPOLYMER BLEND Susanto, Heru; Buchori, Luqman; Sumardiono, Siswo; Fajar, Berkah; Istirokhatun, Titik; Widiasa, I Nyoman
Reaktor Volume 12, Nomor 4, Desember 2009
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (336.104 KB) | DOI: 10.14710/reaktor.12.4.203 – 210

Abstract

This paper demonstrates the preparation of polyethersulfone (PES) ultrafiltration (UF) membranes via wet phase inversion method using either poly(ethylene oxide)-b-poly(propylene oxide)-b- poly(ethylene oxide) (Pluronic®, Plu) or polyethylene glycol (PEG) as hydrophilic modifier. Their effects on membrane structure as well as the resulting membrane performance and their stability in membrane polymer matrix were systematically investigated. The investigated membrane characteristics include surface hydrophilicity (by contact angle), surface chemistry (by FTIR spectroscopy) and water flux measurement. Visualization of membrane surface and cross section morphology was also done by scanning electron microscopy. The membrane performance was examined by investigation of adsorptive fouling and ultrafiltration using solution of bovine serum albumin as the model system. The stability of additive was examined by incubating the membrane in water (40oC) for up to 10 days. The results show that modification effects on membrane characteristic and low fouling behavior were clearly observed. Further, amphiphilic Pluronic generally showed better performance than PEG.   
INVESTIGASI PENGARUH KONDISI LALU LINTAS DAN ASPEK METEOROLOGI TERHADAP KONSENTRASI PENCEMAR SO2 DI KOTA SEMARANG Istirokhatun, Titik; Agustini, Ita Tetriana; Sudarno, Sudarno
Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan Vol 13, No 1 (2016): Maret 2016
Publisher : Departemen Teknik Lingkungan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (893.083 KB) | DOI: 10.14710/presipitasi.v13i1.21-27

Abstract

The  presence  of  air  pollution  in  ambient  air  is  closely  related  to  the incidence  of  adverse reactions affecting human health. One of harmful pollutants and potentially major cause health problems is sulfur dioxide (SO 2 ). The number of vehicles that are passing and queuing on the crossroads  because  of  traffic light can  affect  the  concentration  of  SO 2 .  Besides,  in  these locations  there  are a lot of road users  which  are  potentially  exposed  by  contaminants, so information about the concentration of SO 2  is important to know. This study aimed to investigate the  impact  of  meteorological  factors  and  the  number  of vehicles  on  SO 2   concentrations. Impinger was used for air sampling, and pararosaniline method was used for determining SO 2  concentration. Sampling and calculation  of the number of passing vehicles were performed 3 times ie in the morning, afternoon and evening. Based on the results of the study, the highest concentrations of SO 2  were on the range of 15-21 mg/Nm3.
KUALITAS UDARA DALAM RUANG DI DAERAH PARKIR BASEMENT DAN PARKIR UPPERGROUND (STUDI KASUS DI SUPERMARKET SEMARANG) Huboyo, Haryono Setiyo; Istirokhatun, Titik; Sutrisno, Endro
Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan Vol 13, No 1 (2016): Maret 2016
Publisher : Departemen Teknik Lingkungan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (326.726 KB) | DOI: 10.14710/presipitasi.v13i1.8-12

Abstract

Ever increasing building growth in urban areas is limited by land availability. Lack of space in this area lead to build high rise building rather landed building. In this type of building, parking area  is  built  in  the  basement  and  or upperground  inside  the  building.  Within  this  enclosed space,  indoor  air quality  might  a  problem.  This  study  focus  to  compare  emerged pollutants between  basement  parking  area  and  upperground  parking  area in  supermarket  building.  The dust  sampler,  the  impinger  and  the  CO monitor  were  used  to  measure  TSP,  NO 2   and  CO concentrations respectively  in  these  areas  during  supermarket  operations.  In  the basement area,  in  particular,  the  TSP  concentrations  tend  to  exceeds  300 µg/m 3   mainly  at  weekend period. While for NO 2  and CO concentrations still meet the air quality standard. Based on these findings it seems the main source of pollutants was derived from dust resuspension. Thus, the mitigation measures to reduce this dust resuspension should be emphasized in order to prevent air quality deterioration in the basement parking area.
POTENSI CHLORELLA SP. UNTUK MENYISIHKAN COD DAN NITRAT DALAM LIMBAH CAIR TAHU Istirokhatun, Titik; Aulia, Mustika; Utomo, Sudarno
Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan Vol 14, No 2 (2017): September 2017
Publisher : Departemen Teknik Lingkungan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (188.145 KB) | DOI: 10.14710/presipitasi.v14i2.88-96

Abstract

In order to examine the potential use of tofu-processing wastewater as growth media for microalgae, this research was conducted by cultivating microalgae in varying concentrations. The type of microalga selected in the experiment was Chlorella sp. due to its high reproductive rate. The ability of Chlorella sp. in removing the levels of COD and nitrate contained in the tofu liquid waste were also investigated. This study examined the microalgae growth rate, microalgae cell abundance values, reduced organic levels of COD and nitrate of Chlorella sp which cultivated in tofu wastewater medium. The optimum growth of Chlorella sp was found at 30% v/v of tofu wastewater which reduce COD and nitrate up to 77.40% and 30.03% respectively. From this study, we concluded that tofu-processing wastewater is effective to use as microalgae growth media and at the same time, effective to eliminate COD and nitrate.
ANALISA PENGARUH KELEMBABAN KAYU TERHADAP KONSENTRASI PM 2,5 DALAM DAPUR BERBAHAN BAKAR KAYU SKALA REPLIKASI DAN RUMAH TANGGA Istirokhatun, Titik; Wardhan, Irawan Wisnu; Primelya, Azaria
Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan Vol 8, No 1 (2011): Vol 8, No 1 (2011)
Publisher : Departemen Teknik Lingkungan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (282.994 KB) | DOI: 10.14710/presipitasi.v8i1.8-13

Abstract

PM2,5  adalah salah satu polutan dari aktivitas memasak rumah tangga berbahan bakar kayu yang berpotensi besar menjadi penyebab masalah kesehatan di sejumlah negara berkembang di dunia (Huboyo, dkk, 2009). Tujuan penelitian ini adalah untuk mengetahui pengaruh kelembaban kayu terhadap konsentrasi PM2,5 pada proses pembakaran. Penelitian dilakukan pada  skala laboratorium dengan menggunakan reaktor sederhana sebagai dapur  replikasi, dan skala lapangan di 10 rumah yang menggunakan bahan bakar kayu dalam aktivitas memasak. Dari hasil penelitian skala replikasi dihasilkan bahwa kelembaban kayu terhadap distribusi massa PM2,5 memiliki hubungan yang cukup, karena adanya kontrol udara sehingga partikel yang  dihasilkan dapat tertampung dengan baik. Sedangkan pada penelitian pada dapur rumah tangga menunjukkan tidak ada satu pun hubungan antara distribusi massa PM2,5 dengan 4 faktor yaitu lama memasak, penggunaan kayu, laju pembakaran dan kelembaban kayu, karena proses memasak setiap sampel berbeda. Dari hasil penelitian skala replikasi semakin tinggi kelembaban maka semakin tinggi konsentrasi PM2,5  yang dihasilkan, hal ini erat kaitannya dengan dilakukannya kontrol udara serta waktu pembakaran. Hasill penelitian pada dapur rumah tangga mengindikasikan  kelembaban kayu tidak mempengaruhi konsentrasi PM2,5 karena adanya pengaruh angin, tambahan bahan bakar yang digunakan serta faktor lainnya.
Produksi Glukosamin melalui Hidrolisis Kitosan Menggunakan Irradiasi Microwave Rokhati, Nur; Istirokhatun, Titik; Marpaung, Reisa Novita; Utomo, Ananda Dwi
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2017: PROSIDING SNTKK
Publisher : Prosiding Seminar Nasional Teknik Kimia "Kejuangan"

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

Abstract

Glucosamine (2-amino-2-deoxy-glucose) is an amino-monosaccharide from chitosan, which has many usesin the field of health, especially for the joints, bones, and teeth. Glucosamine can be obtained by the completehydrolysis of chitosan. The influence of microwave irradiation on the chitosan hydrolysis with catalyzed byhydrochloric acid was studied. The hydrolyzed chitosan was characterized by reducing sugar measurement,and FT-IR analysis. The results were compared between hydrolysis using conventional heating andmicrowave irradiation. Microwave irradiation can increase the reaction rate of glucosamine formation.Under the condition of microwave irradiation, the yield of glucosamine is 72.67% after 20 min hydrolysis.While to obtain yield glucosamine 70% required 2 hours for hydrolysis using conventional heating.Chemical structure by FTIR and the reducing sugar content of the glucosamine produced not different withthe glucosamine purchased from Sigma-Aldrich.
KONTRIBUSI PARAMETER METEOROLOGI DAN KONDISI LALU LINTAS TERHADAP KONSENTRASI PENCEMAR NO2 DI KOTA SEMARANG Istirokhatun, Titik; Ratnasari, Elaeis Noviani; Utomo, Sudarno
Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan Vol 13, No 2 (2016): September 2016
Publisher : Departemen Teknik Lingkungan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (650.752 KB) | DOI: 10.14710/presipitasi.v13i2.48-56

Abstract

Air pollution and its public health effects are drawing increasing concern from the environmental health research community, environmental regulatory agencies, industries as well as public. Nitrogen dioxide (NO2) is one of those common air pollutants that potentially major cause health problems. Transportation contributed most of the air pollution. In addition, the number of vehicles that are passing and queuing on the crossroads because of traffic light can affect the concentration of NO 2. Besides, in these places there are a lot of road users which are potentially exposed by contaminants, so information about the concentration of NO2 on road side is important to know. This study aimed to investigate the impact of meteorological factors and the number of vehicles on NO2 concentrations. Impinger fritted bubler was used for air sampling, and Griess Saltzman method was used for determining NO2 concentration. Sampling and calculation of the number of passing vehicles were performed 3 times ie in the morning, afternoon and evening. Based on the results of the study, the highest concentrations of NO2 were on the range of 0.7-4.2 mg/Nm3.
Microwave Irradiation-Assisted Chitosan Hydrolysis Using Cellulase Enzyme Rokhati, Nur; Pramudono, Bambang; Istirokhatun, Titik; Susanto, Heru
Bulletin of Chemical Reaction Engineering & Catalysis 2018: BCREC Volume 13 Issue 3 Year 2018 (SCOPUS and Web of Science Indexed, December 2018)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (493.463 KB) | DOI: 10.9767/bcrec.13.3.2378.466-474

Abstract

The influence of microwave irradiation on the chitosan hydrolysis catalyzed by cellulase enzyme was studied. The hydrolyzed chitosan was characterized by measuring its viscosity and reducing sugar. Further, it was also characterized by Fourier-Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD), and Scanning Electron Microscope (SEM). The classical Michaelis-Menten kinetic parameters were measured by analyzing the amount of reducing sugars. The results were compared with the hydrolysis by using conventional shaker incubator. The hydrolysis reaction time needed to obtain similar reducing sugar yield was significantly lower for microwave irradiation than shaker incubator. On the other hand, the reduction rate of the relative viscosity was significantly higher for the hydrolysis of chitosan using shaker incubator. A significant difference in chemical structure was observed between hydrolysis using microwave irradiation and shaker incubator. Overall, the result showed that the hydrolysis behavior of chitosan using microwave irradiation is significantly different with using shaker incubator. Copyright © 2018 BCREC Group. All rights reservedReceived: 19th March 2018; Revised: 19th June 2018; Accepted: 25th June 2018How to Cite: Rokhati, N., Pramudono, B., Istirokhatun, T., Susanto, H. (2018). Microwave Irradiation-Assisted Chitosan Hydrolysis Using Cellulase Enzyme. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 466-474 (doi:10.9767/bcrec.13.3.2378.466-474)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2378.466-474