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Studying Impact of Different Precipitating Agents on Crystal Structure, Morphology and Photocatalytic Activity of Bismuth Oxide Yayuk Astuti; Arnelli Arnelli; Pardoyo Pardoyo; Amilia Fauziyah; Siti Nurhayati; Arum Dista Wulansari; Rizka Andianingrum; Hendri Widiyandari; Gaurav A. Bhaduri
Bulletin of Chemical Reaction Engineering & Catalysis 2017: BCREC Volume 12 Issue 3 Year 2017 (December 2017)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (480.945 KB) | DOI: 10.9767/bcrec.12.3.1144.478-484

Abstract

Bismuth oxide (Bi2O3) is a well-studied photocatalyst for degradation of various environmental contaminants. In this research Bi2O3 has been synthesized by precipitation method using two different bases (NH4OH and NaOH). The samples thus obtained were then analyzed using FTIR, XRD, and SEM for surface functionalization, crystal structures and morphological differences, respectively. The Bi2O3 precipitated using NH4OH showed a flower like structure made up of individual plates having α-Bi2O3 crystal structure. The precipitate obtained using NaOH showed a honeycomb like flower structure with a mixture of both α-Bi2O3 and γ-Bi2O3 crystal structure. Degradation of methyl orange (MO) was used as a model system to test the photocatalytic activity of the bismuth oxide. The Bi2O3 synthesized using NH4OH showed superior photocatalytic degradation of methyl orange than the one synthesized using NaOH. 
The Effect of White Turmeric Extract (Curcuma Zedoaria) and Lactobacillus sp Herbal Mixture as Feed Additive on Animal Productivity Yayuk Astuti; Mega Bara Cahyantari
Journal of Science & Science Education Vol 4 No 1 (2020): JoSSE Vol. 4 No. 1 (May 2020)
Publisher : Faculty of Science and Mathematics, Universitas Kristen Satya Wacana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24246/josse.v4i1p1-9

Abstract

This study was conducted to determine the effect of herbal white turmeric extract (Curcuma zedoaria) with Lactobaccilus sp on the productivity of livestock. The test subjects within this study are 50 broiler chickens aged 0 days which were divided equally into two observation groups, namely the control group (A) and the treated group (B). The treatments are carried out as follows: A = no animal herbal mixture was added into the drinking water; B = drinking water was added with herbal mixture. Average body weight of the chickens were (A) 460 g and (B) 484 g, the feed conversion ratio values for chicken aged 6 and 13 days respectively are 0.696 (A); 0.644 (B) and 1.25 (A); 1.18 (B), while the performance index value (IP) of broiler chickens aged 6 and 13 days were 335 (A); 390 (B) and 272 (A); 315 (B), consecutively. In this study the addition of herb as feed additives into broiler chicken drinking water can increase the average body weight of the treatment group compared to the control group, the treatment group has a lower FCR value indicating good feed efficiency and IP values ​​above 300 implying good breeding process.
LiOH/Coconut Shell Activated Carbon Ratio Effect on the Electrical Conductivity of Lithium Ion Battery Anode Active Material Annisa Syifaurrahma; Arnelli Arnelli; Yayuk Astuti
Molekul Vol 16, No 3 (2021)
Publisher : Universitas Jenderal Soedirman

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (579.245 KB) | DOI: 10.20884/1.jm.2021.16.3.805

Abstract

A lithium ion battery anode active material comprised of LiOH (Li) and coconut shell activated carbon (AC) has been synthesized with Li/AC ratios of (w/w) 1/1, 2/1, 3/1, and 4/1 through the sol gel method. The present study aims to ascertain the best Li/AC ratio that produces an anode active material with the best electrical conductivity value and determine the characteristics of the anode active material in terms of functional groups, surface area, crystallinity, and capacity. Based on the electrical conductivity test using LCR, the active material Li/AC 2/1 had the highest electrical conductivity with a value of 2.064x10-3 Sm-1. The conductivity achieved was slightly smaller than that of the active material with no addition of LiOH on the activated carbon at an electrical conductivity of 5.434x10-3 Sm-1. The FTIR spectra of the activated carbon and Li/AC 2/1 showed differences with in the Li-O-C group absorption at 1075 cm-1 wavenumber and the wide absorption in the area of 547.5 cm-1 that represents Li-O vibration. Based on the results of SAA, the activated carbon had a larger surface area than Li/AC 2/1 at 17.057 m2g-1 and 5.615 m2g-1, respectively. The crystallinity of both active materials was low shown by the widening of the diffraction peaks. Tests with cyclic voltammetry (CV) proved that there was a reduction-oxidation reaction for the two samples in the first cycle with a large charge and discharge capacities of the activated carbon of 150.989 mAh and 92.040 mAh, while for Li/AC 2/1 they were 91.103 mAh and 47.580 mAh.
Bismuth Oxide Prepared by Sol-Gel Method: Variation of Physicochemical Characteristics and Photocatalytic Activity Due to Difference in Calcination Temperature Yayuk Astuti; Brigita Maria Listyani; Linda Suyati; Adi Darmawan
Indonesian Journal of Chemistry Vol 21, No 1 (2021)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.53144

Abstract

Research on synthesis of bismuth oxide (Bi2O3) using sol-gel method with varying calcination temperatures at 500, 600, and 700 °C has been done. This study aims to determine the effect of calcination temperature on the characteristics of the obtained products which encompasses crystal structure, surface morphology, band-gap energy, and photocatalytic activity for the decolorization of methyl orange dyes through its kinetic study. Bismuth oxide prepared by sol-gel method was undertaken by dissolving Bi(NO3)3·5H2O and citric acid in HNO3. The mixture was stirred then heated at 100 °C. The gel formed was dried in the oven and then calcined at 500, 600, and 700 °C for 5 h. The obtained products were a pale yellow powder, indicating the formation of bismuth oxide. This is confirmed by the existence of Bi–O and Bi–O–Bi functional groups through FTIR analysis. All three products possess the same mixed crystal structures of α-Bi2O3 (monoclinic) and γ-Bi2O3 (body center cubic), but their morphologies and band gap values are different. The higher the calcination temperature, the larger the particle size and the smaller the band gap value. The accumulative differences in characteristics appoint SG700 to have the highest photocatalytic activity compared to SG600 and SG500 as indicated by its percent degradation value and decolorization rate constant.
Modification of Activated Carbon from Rice Husk using Hexadecyltrimethylammonium Bromide (HDTMA-Br) Surfactant and ZnCl2 activator and Microwaves for Nitrate Ion Adsorption Yeni Aprilia; Arnelli Arnelli; Yayuk Astuti
Jurnal Kimia Sains dan Aplikasi Vol 23, No 11 (2020): Volume 23 Issue 11 Year 2020
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2068.214 KB) | DOI: 10.14710/jksa.23.11.377-382

Abstract

Surfactant Modified Activated Carbon (SMAC) is a surfactant-modified activated carbon product. The surfactant used in this study was the cationic surfactant Hexadecyltrimethylammonium Bromide (HDTMA-Br). These surfactants can change the activated carbon's surface to be positively charged due to the presence of the surfactant hydrophilic groups. This SMAC is more selective in absorbing anions, which in this study is for the adsorption of nitrate anions. This research aims to prepare a new material that is superior to activated carbon in absorbing nitrate anions. This research was conducted in several stages. In the first stage, rice husk was carbonized through pyrolysis at 300°C for 10 minutes. In the second stage, carbon was activated using 30% ZnCl2 and microwaves for 5 minutes and 400 W. The third stage was modifying activated carbon by contacting or adsorbing HDTMA-Br on activated carbon. The concentration of HDTMA-Br varied at 200-400 ppm and the adsorption time was 3-7 hours. The success of the modification was measured by the efficiency of HDTMA-Br in modifying activated carbon. This is supported by the results of the characterization of FTIR, GSA, SEM, and thermodynamic parameters. The resulting SMAC was applied for the adsorption of nitrate anions, and the results were compared to carbon and activated carbon. The results indicate that the best SMAC is formed at an optimum concentration of 300 ppm, within 4 hours, with an adsorption efficiency of 97.345%. The characterization results also show that SMAC has been formed, as evidenced by the presence of a peak at a wavenumber of about 1500 cm-1, a C-N group derived from N(CH3)3 in the HDTMA-Br surfactant structure. The SMAC spectra also appeared weak peaks at the wave number 2918 cm-1, which indicated the CH2-R group stretching from the HDTMA-Br surfactant. SEM image shows that HDTMA-Br has covered the pores of activated carbon. Meanwhile, the SMAC surface area is lower than that of activated carbon. Thermodynamic parameters indicate that HDTMA-Br interacts physically with activated carbon. The adsorption capacity of nitrate anion by SMAC is 3,638 mg/g, higher than carbon and activated carbon.
Synthesis of Sodium Lauryl Sulfate (SLS) and Hexadecyltrimethylammonium Bromide (HDTMA-Br) Surfactant-Modified Activated Carbon as Adsorbent for Pb2+ and NO3- Arnelli Arnelli; Rahmatul Fazira; Yayuk Astuti; Ahmad Suseno
Jurnal Kimia Sains dan Aplikasi Vol 23, No 11 (2020): Volume 23 Issue 11 Year 2020
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2977.337 KB) | DOI: 10.14710/jksa.23.11.396-402

Abstract

The adsorption efficiency and selectivity of activated carbon as an adsorbent for ions can be improved. One way is to convert activated carbon into surfactant modified activated carbon (SMAC). The surfactants used in this study were the anionic surfactant Sodium Lauryl Sulfate (SLS) and the cationic surfactant hexadecyltrimethylammonium bromide (HDTMA-Br). This research aims to synthesize SMAC to obtain a material with a surface charge and absorb ions better than activated carbon. This research consisted of four stages. The first step was the carbonization of rice husks using a pyrolysis reactor at 400°C for 1 hour. The second stage was carbon activation using 30% ZnCl2 and microwave radiation for 5 minutes and 400 W. The third stage was the modification of activated carbon and characterization by FTIR, SEM, SAA. The fourth stage was the adsorption of Pb cations and nitrate anions by carbon, activated carbon, and SMAC. Several variables were applied, such as the type of surfactant, time, and method of modification. There are three ways of modification: (1) method A, in which activated carbon is brought into contact with SLS then HDTMA-Br. (2) Method B in which activated carbon was contacted with HDTMA-Br then SLS. (3) Method C in which activated carbon was brought into contact with SLS together with HDTMA-Br. All variables were investigated. The results showed that the optimum time for making SMAC for both surfactants was 4 hours, the optimum concentrations of SLS and HDTMA-Br were 60 and 300 ppm, respectively. SMAC made by the C method was the most effective at adsorbing Pb2+ and NO3- with adsorption capacities of 1.376 and 0.896 mg/g, respectively. The success of SMAC synthesis was evidenced by the S=O and (CH3)3N+ groups in the FTIR spectra. The SMAC surface area is smaller than activated carbon, 14.472 m2/g, but the surface morphology is smoother and more homogeneous.
Korosi Besi dengan Elektrolit H2SO4 dan Karakterisasi Produk Richard Leonardo Sianturi; Linda Suyati; Yayuk Astuti
Greensphere: Journal of Environmental Chemistry Vol 1, No 2 (2021): Volume 1 Issue 2 tahun 2021
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (405.973 KB) | DOI: 10.14710/gjec.2021.12910

Abstract

Telah dilakukan penelitian tentang penentuan laju reaksi korosi pada besi dalam air dan elektrolit asam sulfat. Penelitian ini bertujuan untuk menentukan laju korosi dengan menggunakan metode pengurangan berat, menentukan karakterisitik produk dengan FTIR untuk mengidentifikasi gugus fungsi dari produk, menentukan karakteristik XRD untuk mengetahui struktur lingkup material dari produkdan menentukan kinetika reaksi produk terbaik. Metode yang dilakukan pada penelitian ini terdiri dari 3 tahap, yaitu preparasi larutan H2SO4  0.0675M, 0.125M, 0.25M, 0.5M dan 1M, karakterisasi produk dan uji kinetika reaksi dengan variasi  waktu 0, 15, 30, 45, 60 dan 75 menit. Hasil  penelitian diperoleh  endapan warna coklat dan karakterisasi FTIR Fe2O3 terlihat pada puncak 586 cm-1   Produk hasil reaksi antara besi dengan H2SO4 muncul puncak yang sedikit bergeser pada sudut 2θ 24,10o, 32,90odan 49,55o. Lalu pada hasil reaksi korosi besi dengan H2O muncul puncak sudut 2θ pada 24,36o, 33,24odan 49,43o. Peningkatan kecepatan korosi seiring dengan meningkatnya konsentrasi dari larutan asam sulfat. Konstanta laju order satu dan dua berturut-turut sebesar 1.28 x 10-3 menit-1 dan 2,9  x 10-4 M-1 menit-1.  
Pembuatan Karbon Aktif Termodifikasi Surfaktan Sodium Lauryl Sulphate (SMAC-SLS) dari Tempurung Kelapa Menggunakan Aktivator ZnCl2 dan Gelombang Mikro Sebagai Adsorben Kation Pb(II) Anisyah Anisyah; Arnelli Arnelli; Yayuk Astuti
Greensphere: Journal of Environmental Chemistry Vol 1, No 1 (2021): Volume 1 Issue 1 tahun 2021
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (857.301 KB) | DOI: 10.14710/gjec.2021.10733

Abstract

Penelitian tentang modifikasi karbon aktif tempurung kelapa dengan surfaktan sodium lauryl sulphate (SLS) telah dilakukan sebagai adsorben logam Pb(II). Penelitian ini bertujuan untuk membuat material baru Surfactant Modificated Activated Carbon (SMAC) dari tempurung kelapa yang lebih unggul dari karbon aktif untuk adsorben logam Pb(II).  Penelitian ini terdiri dari beberapa tahap, tahap pertama adalah  karbonisasi tempurung kelapa mengunakan pirolisis pada temperatur 400oC selama 1 jam, tahap kedua aktivasi menggunakan ZnCl2 30% dan radisasi gelombang mikro dengan daya bervariasi 80 -800 W selama waktu bervariasi 1 – 9 menit, tahap ketiga modifikasi karbon aktif menggunakan SLS 60 ppm selama 4 jam dan selanjutnya tahap aplikasi SMAC untuk adsorben logam Pb. Karakterisasi SMAC dilakukan adalah dengan FTIR, GSA, SEM dan data termodinamika. keberhasilan adsorpsi SMAC diukur dengan menentukan kapasitas adsorpsi.  Hasil modifikasi menunjukkan karbon aktif dapat mengadsorpsi SLS sebesar 1,496 mg/g. Karakterisasi SMAC  dengan FTIR menunjukkan adanya pucak S=O pada bilangan gelombang 1341 cm-1, karakterisasi dengan GSA menunjukkan luas area SMAC lebih kecil dari karbon aktif yaitu sebesar 3,924 m2/g, morfologi permukaan SMAC sebagian besar tertutup oleh surfaktan SLS dan data termodinamika memberikan nilai entalpi sebesar -10,282 kJ/mol yang menunjukkan interaksi antara karbon aktif dan SLS merupakan interaksi atau adsorpsi secara fisik. SMAC efektif mengadsorpsi logam Pb(II) dengan efisiensi sebesar 99,89% dan kapasitas sebesar 1,498 mg/g dan interaksi antara SMAC dengan kation Pb (II) merupakan interaksi elektrostatis.Kata Kunci: SMAC, Kapasitas Adsorpsi, kation Pb
Use of Microwave Radiation for Activating Carbon from Rice Husk Using ZnCl2 Activator Arnelli Arnelli; Ulya Hanifah Henrika Putri; Fandi Nasrun Cholis; Yayuk Astuti
Jurnal Kimia Sains dan Aplikasi Vol 22, No 6 (2019): Volume 22 Issue 6 Year 2019
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3324.307 KB) | DOI: 10.14710/jksa.22.6.283-291

Abstract

Activated carbon is one of the most commonly used adsorbents in a variety of separation processes because it is inexpensive, and also the design and principal of application are quite simple. The ability of activated carbon as an adsorbent is related to its large surface area and pore volume, varying pore structure, and diverse surface reactivity. The use of microwave radiation can further improve the efficiency of activated carbon adsorption. Micro-waves can affect the pore texture and surface of the activated carbon, but rarely do both practitioners and researchers control these variables influencing the relationship between features and performance of biomass-based activated carbon as an adsorbent at the time of manufacture from the initial stage (carbonation) to carbon application active (e.g., adsorption of heavy metals, surfactants, and organic molecules). This study aims to synthesize activated carbon from rice husk, which has the efficiency and capacity of adsorption of heavy metals such as Pb and activator organic molecules used is ZnCl2 30% and microwave radiation. This research has succeeded in making activated carbon using the ZnCl2 activator and microwave radiation. The time and power of microwave radiation that provides the highest efficiency in the carbon activation process for Pb ion adsorbate, were 7 minutes and 800 W. For phenol adsorbate was 5 minutes at 800 W. The highest efficiency time and concentration of adsorption for Pb ion adsorbate were 40 minutes at 60 ppm while for phenol adsorbate were 5 hours at 100 ppm. The adsorption efficiency for Pb cation adsorbate was 99.57%. While for phenol adsorbate is 81.05%. Characterization with FTIR, SEM-EDX, and SAA showed a C-Cl bond, the pores were visible, and an increased surface area of activated carbon was 36.9 times the surface area of carbon and the pores formed were mesoporous.
Utilization and Characterization of Oyster Shell as Chitosan and Nanochitosan Lia Handayani; Faisal Syahputra; Yayuk Astuti
Jurnal Kimia Sains dan Aplikasi Vol 21, No 4 (2018): volume 21 Issue 4 Year 2018
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3618.511 KB) | DOI: 10.14710/jksa.21.4.224-231

Abstract

Oyster is one of bivalve groups widely consumed by human, thus, it results in producing huge waste shells affecting the environment. One way to increase the value of oyster shells is to process them into chitosan. This study aims to isolate chitin then synthesize it into chitosan and convert chitosan into nano-sized chitosan and analyze the characteristics. The steps to produce chitosan from waste shells included demineralization using HCl 1 N and deproteinization using NaOH 3%. The next step was to convert chitin into chitosan through a deacetylation process using NaOH 50%. After chitosan was formed, it was continued to convert chitosan into nano chitosan particles using ion gelation method with the addition of surfactant (tween 80) and crosslinker (TPP 0.1% and 0.5%). The results showed that yield of transformation chitin into chitosan was 61.1%. Meanwhile, the yield calculated from initial weight of raw material was 18.33% with deacetylation degree value equal to 89.14%. Based on morphological analysis using SEM, the size of chitosan particles was not distributed homogeneously that was in the range of 892 nm-1.54 μm, while the nano chitosan particle size obtained was uniformly formed in the range of 679 nm-910 nm.
Co-Authors Abdul Jabbar Adi Darmawan ADI SANTOSO Agriccia Pangestica Saputry Ahmad Suseno Alfi Saadah Alfiansyah Alfiansyah Amilia Fauziyah Anisyah Anisyah Annisa Syifaurrahma Arnelli Arnelli Arum Dista Wulansari Aulia Zahra Ekaningsih Azwar Thaib Bara Yunianto Fathoni Brainy Happy Ana Tasiman Brainy Happy Ana Tasiman Brigita Maria Listyani Cut Rahmawati Daniswara, Lufthansyah Dayadi, Dayadi Didi Dwi Anggoro Didik Setyo Widodo Esti Ayu Faisal Syahputra Fandi Nasrun Cholis Faradina Azahra Zaqia Fauzan Musthafa Febrianti, Devi Fitriani Solichah Galih N. R. Pargiman Gaurav A. Bhaduri Gunawan Gunawan Hartati Hartati Hasim Muzadi Hendri Widiyandari Hendri Widiyandari Hendri Widyandari Husnayani, Husnayani Iis Nurhasanah Iis Nurhasanah Irman, Iriani Isumarni, Isumarni Jamaluddin Ahmad Jumiati Jumiati Khalik, Suhartini Khalik, Suhartini Khoiri, Rahma Lia Handayani Lia Handayani Lia Handayani Linda Suyati Luqman Buchori M. S.H. Yoga S. Majid, Abdul Majid Zainuddin Mega Bara Cahyantari Muh. Rohady Ramadhan Muhammad Rusdi Muslim, Agus Mustanir, Ahmad Nabila Amalia Izaaz Aanisa Narita Rizki Nayla Zahra Kamalia Nonci, Nurjannah Noor Afifah Nur Hidayati Nurhayati Nurhayati Nurhayati Nurhayati Nurlaelah Nurlaelah, Nurlaelah Nurul Latifah Nurwidah, Andi Pandji Triadiyaksa Pardoyo Pardoyo Pardoyo Pardoyo Popi Hadi Wisnu Wardhani Prasetya, Eko Fery Prisca Putri Elesta Pungki Hanipa R Kasau, Nurzin Rahayu, R.A. Yunita Suci Rahayu, Yunita Suci Rahmatul Fazira Rahmawati Rahmawati Ratna Balgis Redi Joko Prasetyo Richard Leonardo Sianturi Rissa Kharismawati Rizka Andianingrum Roni Adi Wijaya Samratusabri Subehan Siringoringo, Eliezer Patardo Siti Fatimah Siti Nurhayati Siti Susanti, Siti Slamet Priyono Subehan, Samratusabri Tamrin, Muh Taslimah Taslimah Teguh Iman Prastyo Titik Lestariningsih Titik Lestariningsih Tri Windarti Tri Windarti Triadiyaksa, Pandji Trie Nanda Mulyana Trisnasari, Damayanti Ulya Hanifah Henrika Putri Vega Norma Rafika Putri Wijayanti, Septi Yeni Aprilia Yusrianti Yusrianti, Yusrianti