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All Journal Bulletin of Chemical Reaction Engineering & Catalysis Jurnal Kimia Riset Indonesian Journal of Chemistry Bubungan Tinggi: Jurnal Pengabdian Masyarakat Jurnal Layanan Masyarakat (Journal of Public Service) Greensphere: Journal of Environmental Chemistry Bulletin of Chemical Reaction Engineering & Catalysis Andan Jejama: Indonesian Journal Of Community Engagement

Alfa Akustia Widati

Department Of Chemistry, Faculty Of Science And Technology, Universitas Airlangga

Author-ID : 3195233

Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Decision Sciences, Operations Research & Management Education Environmental Science Public Health Social Sciences Other

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HIDROLISIS MINYAK JARAK PAGAR MENJADI ASAM LEMAH BEBAS MENGGUNAKAN KATALIS CaO Abdulloh Abdulloh; Alfa Akustia Widati; Faiz Tamamy
Jurnal Kimia Riset Vol. 1 No. 1 (2016): Juni
Publisher : Universitas Airlangga

AbstrakTelah dilakukan hidrolisis minyak jarak pagar (Jatropha curcas oil: JO) menggunakan katalis CaO. Reaksi ini dimaksudkan untuk meningkatkan nilai ekonomis minyak jarak pagar selain biodiesel. Katalis CaO dikalsinasi terlebih dahulu pada suhu 800ᵒC untuk menghindari terjadinya deaktivasi katalis oleh terbentuknya CaCO3. Pada penelitian ini dilakukan karakterisasi katalis CaO meliputi struktur kristal CaO, luas permukaan, jumlah situs basa dan kekuatan kebasaan serta aktivitas katalitiknya. Hasil penelitian menunjukkan, katalis CaO memiliki luas permukaan 26,451 m2/g, kekuatan situs basa (pKB) pada daerah 7,2 < pKBH CaO < 15,0. Hasil uji aktivitas katalis CaO pada reaksi hidrolisis CJO diperoleh konversi CJO menjadi asam lemak bebas (free fatty acid: FFA) sebesar 77,58% pada waktu 60 menit. Kata kunci: hidrolisis, minyak jarak pagar (JO), free fatty acid (FFA), CaO dan situs basa AbstractHydrolysis of Jatropha curcas oil has been carried out using CaO as a catalyst. This reaction is intended to increase the economic value besides biodiesel. CaO catalyst was calcined at a temperature of 800 oC to avoid catalyst deactivation by formation of CaCO3. In this research include the characterization of catalysts CaO crystal structure, surface area, the number of base sites and the strength of basicity and catalytic activity. The results of the analysis showed that CaO catalyst has a surface area of 26.451 m2/g, the number of base sites of 221.77 mmol/g and the strength of base sites (pKBH) in the range of 7.2 < pKBH CaO < 15.0. From catalytic activity test showed that that the use of the catalytic activity of CaO catalyst in the hydrolysis reaction CJO into free fatty acids (FFA) as much as 77.58% for 60 minutes. Keywords: hydrolysis, Jatropha curcas oil (JO), free fatty acid (FFA), CaO and base site

SUHU DAN WAKTU HIDROTERMAL DALAM SINTESIS ZSM-5 DARI METAKAOLIN Hartati Hartati; Alfa Akustia Widati; Aning Purwaningsih; Alfinda Novi Kristanti; Anik Fathur Rohmah
Jurnal Kimia Riset Vol. 3 No. 1 (2018): Juni
Publisher : Universitas Airlangga

AbstrakSintesis ZSM-5 dilakukan dari metakaolin terdealuminasi tanpa penambahan templat organik. Sintesis dilakukan melalui pengaturan suhu hidrotermal mulai suhu 120oC, 150o, dan 170oC. Hasil sintesis dikarakterisasi dengan difraktometer sinar-X , spektrometer FTIR, dan adsorpsi/desorpsi nitrogen. Pengaturan suhu hidrotermal pada 120oC selama 24 jam belum menghasilkan ZSM-5, sedangkan sintesis pada suhu 150oC selama 24 jam diperoleh hasil ZSM-5 dengan kristal yang cukup baik. Hidrotermal pada 170o tetap dapat membentuk ZSM-5 dengan pengotor mordenit dan kurang kristalin dibandingkan sintesis pada 150oC. Kata kunci: AbstrakSintesis ZSM-5 dilakukan dari metakaolin terdealuminasi tanpa penambahan templat organik. Sintesis dilakukan melalui pengaturan suhu hidrotermal mulai suhu 120oC, 150o, dan 170oC. Hasil sintesis dikarakterisasi dengan difraktometer sinar-X , spektrometer FTIR, dan adsorpsi/desorpsi nitrogen. Pengaturan suhu hidrotermal pada 120oC selama 24 jam belum menghasilkan ZSM-5, sedangkan sintesis pada suhu 150oC selama 24 jam diperoleh hasil ZSM-5 dengan kristal yang cukup baik. Hidrotermal pada 170o tetap dapat membentuk ZSM-5 dengan pengotor mordenit dan kurang kristalin dibandingkan sintesis pada 150oC. Kata kunci: ZSM-5, metakaolin, terdealuminasi, tanpa templat, pengaturan suhu dan waktu Abstract Synthesis of ZSM-5 is carried out from dealuminated metakaolin without the addition of organic template. The synthesis is done by setting the hydrothermal temperature from 120oC, 150oC, and 170oC. The results were characterized by an X-ray diffractometer, FTIR spectrometer, and nitrogen adsorption / desorption. Hydrothermal temperature setting at 120oC for 24 hours has not produced ZSM-5, while the synthesis at 150oC for 24 hours was obtained ZSM-5 with good crystals. Hydrothermal at 170 °C can still form ZSM-5 with mordenite impurities and less crystalline than synthesis at 150 °C. Keywords: ZSM-5, dealuminated metakaolin, without organic templates, temperature and time settings Abstract Synthesis of ZSM-5 is carried out from dealuminated metakaolin without the addition of organic template. The synthesis is done by setting the hydrothermal temperature from 120oC, 150oC, and 170oC. The results were characterized by an X-ray diffractometer, FTIR spectrometer, and nitrogen adsorption / desorption. Hydrothermal temperature setting at 120oC for 24 hours has not produced ZSM-5, while the synthesis at 150oC for 24 hours was obtained ZSM-5 with good crystals. Hydrothermal at 170 °C can still form ZSM-5 with mordenite impurities and less crystalline than synthesis at 150 °C. Keywords: ZSM-5, dealuminated metakaolin, without organic templates, temperature and time settings

Direct Synthesis of Highly Crystalline ZSM-5 from Indonesian Kaolin Hartati Hartati; Alfa Akustia Widati; Tanti Kartika Dewi; Didik Prasetyoko
Bulletin of Chemical Reaction Engineering & Catalysis 2017: BCREC Volume 12 Issue 2 Year 2017 (August 2017)
Publisher : Department of Chemical Engineering - Diponegoro University

Direct synthesis of ZSM-5 from Indonesian kaolin without calcination for the formation of metakaolin was done through the addition of an alkaline solution (sodium fluoride and sodium hydroxide) and the fusion using sodium hydroxide. Crystallization was conducted through hydrothermal method at 80 °C for four days. XRD diffractogram and FTIR spectra showed that the addition of sodium fluoride solution in the ratio Si/Al = 100 could produce highly crystalline ZSM-5, whereas the use of a sodium hydroxide solution and fusion process did not produce the crystalline ZSM-5.

IMPRINTING ZEOLITE-MODIFIED GLASSY CARBON AS A VOLTAMMETRIC SENSOR FOR URIC ACID Miratul Khasanah; Muji Harsini; Alfa Akustia Widati
Indonesian Journal of Chemistry Vol 13, No 2 (2013)
Publisher : Universitas Gadjah Mada

Development of the uric acid sensor through coating of glassy carbon (GC) electrode with imprinting zeolite (IZ) was carried out. Zeolite was synthesized by mixing TEOS, TBOT, TPAOH, and water followed by hydrothermal process. Zeolite was molded together with uric acid to produce IZ. The deposition potential of IZ and uric acid to the GC surface was -0.6 V during 150 sec with addition of KNO3 0.02 M as supporting electrolyte. The method gives linearity of 0.9834 (concentration 5.6x10-9M - 2.8x10-8 M), precision 1.89 - 7.65%, sensitivity 0.33 µA/nM/cm2, limit of detection 5.9x10-9 M, and accuracy 96.26 ± 0.55% (n = 5). The developed sensor showed a high selectivity toward uric acid. The presence of ascorbic acid, creatine, and creatinine with an equal concentration with uric acid did not interfere on the uric acid analysis.

Preparation of Water Repellent Layer on Glass Using Hydrophobic Compound Modified Rice Hull Ash Silica Alfa Akustia Widati; Nuryono Nuryono; Dessy Puspa Aryanti; Madjid Arie Wibowo; Eko Sri Kunarti; Indriana Kartini; Bambang Rusdiarso
Indonesian Journal of Chemistry Vol 18, No 4 (2018)
Publisher : Universitas Gadjah Mada

In this study water repellent layered glass has been prepared by coating silica (SiO2) combined with a hydrophobic silane compound. SiO2 was extracted from rice hull ash and two silane compounds, namely hexadecyltrimethoxysilane (HDTMS) and trimethylchlorosilane (TMCS) were used. Coating was performed through two deposition techniques, i.e. one step (mono-layer) and layer by layer (LBL, multi-layer). The effect of silane to SiO2 mole ratio, silane type and layer number on the glass characters was evaluated. Characterization included hydrophobicity, transparency, surface roughness and stability of coating. Results showed that increasing the mole ratio of silane to SiO2 and the layer number increased the hydrophobicity of the glass surface. The optimum mole ratio was 5:1 and the significant increase of contact angle occurred at lower mole ratio, but the stability tends to be increased at higher mole ratio. For HDTMS-SiO2 layer, the technique of LBL technique produced a coating with higher hydrophobicity and transparency than single-stage one. The LBL technique produced the highest water contact angle of 103.7° with transmittance of 96%, while for TMCS-SiO2 layer the one stage technique produced hydrophobic layer with higher water contact angle of 108.0° and transparency about 94.52%. The prepared hydrophobic glasses were relatively stable in polar and non-polar solvents, but unstable to ambient conditions.

Imprinted Zeolite Modified Carbon Paste Electrode as a Selective Sensor for Blood Glucose Analysis by Potentiometry Miratul Khasanah; Alfa Akustia Widati; Usreg Sri Handajani; Muji Harsini; Bahrotul Ilmiah; Irene Dinda Oktavia
Indonesian Journal of Chemistry Vol 20, No 6 (2020)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.49820

Imprinted zeolite modified carbon paste (carbon paste-IZ) electrode had been developed as a sensor to analyze blood glucose content by potentiometry. The used zeolite was Lynde Type A (LTA) that synthesized with a mole ratio of Na2O, Al2O3, SiO2 and H2O of 4:1:1.8:270, respectively while non-imprinted zeolite was prepared with a mole ratio of glucose/Si of 0.0306. Glucose was then extracted from the zeolite framework using hot water (80 °C) to produce imprinted zeolite (IZ). The carbon paste-IZ electrode prepared from activated carbon, paraffin pastilles, and IZ with a mass ratio of 5:4:1 showed the best performance. The modified electrode demonstrated the measurement range of 10–4-10–2 M, the Nernst factor of 29.55 mV/decade, the response time less than 120 s, and the detection limit of 5.62 × 10–5 M. Ascorbic acid, uric acid, urea and creatinine did not interfere on the glucose analysis by potentiometry. Comparison test with spectrophotometry showed an accuracy of (90.7 ± 1.4)% (n = 5), while the application of the electrode to analyze five spiked serum samples showed recovery of (92.2 ± 1.3)% (n = 5). The electrode was stable for up to 9 weeks (168 times usage). Based on its performance, the developed electrode can be applied to analyze glucose in human serum sample and recommended for used in the medical field.

Ion Impregnation Effect of Fe, Cu, Cr-attributed Mordenite on Stearic Acid Cracking Abdulloh Abdulloh; Ulfa Rahmah; Satya Candra Wibawa Sakti; Alfa Akustia Widati; Ahmadi Jaya Permana; Rochadi Prasetya; Musbahu Adam Ahmad; Mochamad Zakki Fahmi
Indonesian Journal of Chemistry Vol 22, No 3 (2022)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.71126

The improvement in the design of mordenite-based catalysts focuses on the present study to fulfill the massive demand for bio-aviation fuel (BAF) as renewable energy. Modification of the mordenite through ionic impregnation of Fe, Cu, and Cr, has supported the mordenite to perform with better efficiency and activity in catalyzing the cracking process of stearic acid. The adjustment on catalytic activity was carried out by simply reacting the catalyst with stearic acid at 190 °C and investigating cracking products with Gas Chromatography-Mass Spectroscopy. The results of the GC-MS test of the cracking product showed the formation of alkane-alkene and aromatic compounds. BAF was selectively obtained (30.27%) when the reaction was catalyzed by FeCuCr/mordenite catalyst. The BAF derived from FeCuCr/mordenite contained hydrocarbons that include xylene, mesitylene, dodecane, tridecane, tetradecane, and pentadecane. However, reduced selectivity was realized (19.85%) when the reaction was catalyzed by nano FeCuCr/mordenite. Its hydrocarbon constituents include benzene, tetradecane, and pentadecane compounds.

Pelatihan Pembuatan Hand Sanitizer Menuju Desa Cerdas Kesehatan Di Desa Cangkir, Kecamatan Driyorejo, Kabupaten Gresik Qurrota A'yuni; Alfa Akustia Widati; Harsasi Setyawati; Atik Widiyanti; Purkan Purkan; Miratul Khasanah; Tokok Ardiarto; A. Budi Prasetyo; Aning Purwaningsih; Siti Wafiroh; Sri Sumarsih; Rico Ramadhan; Sofijan Hadi; Kariza Makanty; Ahlan Riwahyu Habibi; Aulianitha Salsabella
Bubungan Tinggi: Jurnal Pengabdian Masyarakat Vol 4, No 2 (2022)
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/btjpm.v4i2.5253

Hand sanitizer merupakan cairan atau gel pembersih tangan yang memiliki sifat sebagai antibakteri dalam menghambat hingga membunuh bakteri. Dengan demikian hand sanitizer lebih efektif dalam membasmi kuman. Berdasarkan penelitian The Centers for Disease Control and Prevention (CDC), hand sanitizer dengan kandungan alkohol minimal 60% dapat berfungsi sebagai antibakteri maupun antivirus. Hand sanitizer pernah menjadi barang langka di puncak pandemi pada tahun 2020, karena pembelian yang masif dari masyarakat Indonesia. Langkanya hand sanitizer di beberapa toko dan apotek membuat harganya menjadi mahal. Kegiatan Pengabdian Kepada Masyarakat ini bertujuan untuk meningkatkan pengetahuan akan pentingnya kesehatan dan kemungkinan penyebaran kuman terutama virus dan bakteri serta upaya untuk mengantisipasinya. Tujuan yang lain yaitu untuk meningkatkan keterampilan masyarakat dalam pembuatan hand sanitizer. Rangkaian kegiatan ini diselenggarakan di Desa Cangkir, Kecamatan Driyorejo, Kabupaten Gresik pada Bulan November-Desember 2021 secara luring dengan menerapkan protokol kesehatan dengan peserta Ibu-Ibu PKK dan Kader PKK. Kegiatan ini dilakukan melalui metode pendampingan dan demonstrasi dengan presentasi materi dan praktik langsung. Kegiatan ini memberikan dampak yang positif bagi masyarakat Desa Cangkir dalam menghadapi Pandemi Covid-19 saat ini. Hand sanitizer is a liquid or gel that has antibacterial properties to inhibit and kill bacteria. Thus, hand sanitizer is more effective in eradicating germs. Based on research from The Centers for Disease Control and Prevention (CDC), alcohol-based hand sanitizers that contain at least 60% alcohol can function as both antibacterial and antivirus. Hand sanitizer was once a scarce item at the height of the pandemic in 2020, due to massive purchases from the Indonesian people. The scarcity of hand sanitizers in some shops and pharmacies makes the price expensive. This Community Service activity aims to increase knowledge of the importance of health and the possibility of spreading germs, especially viruses and bacteria, and efforts to anticipate them. Another aim is to improve community skills in making hand sanitizers. This series of activities were held in Cangkir Village, Driyorejo District, Gresik Regency in November-December 2021 via offline by implementing health protocols with PKK women and PKK Cadres as participants. This activity is carried out through mentoring and demonstration methods with presentations and hands-on practice. This activity has a positive impact on the Cangkir Village community in dealing with the current Covid-19 Pandemic.

Pemanfaatan Teknologi Digital sebagai Media Pembelajaran untuk Guru SMA-SMP Muhammadiyah Gresik Alfa Akustia Widati; Fatiha Khairunnisa; Satya Candra Wibawa Sakti; Ganden Supriyanto; Mochamad Zakki Fahmi; Imam Siswanto; Hartati Hartati; Ali Rohman
Bubungan Tinggi: Jurnal Pengabdian Masyarakat Vol 5, No 2 (2023)
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/btjpm.v5i2.6873

Guru mempunyai kewajiban besar memastikan anak didik memahami materi pelajaran. Namun, waktu belajar di kelas yang terbatas dan beragamnya kemampuan siswa menyebabkan metode pembelajaran tatap muka di kelas menjadi kurang efektif dalam meningkatkan pemahaman siswa. Tantangan dunia pendidikan menuntut guru harus memiliki kompetensi penguasaan teknologi digital. Video pembelajaran yang disajikan secara virtual adalah salah satu metode pembelajaran efektif untuk siswa. Oleh karena itu, guru seyogyanya memiliki kemampuan membuat video digital secara mandiri. Pengenalan jenis teknologi digital, instalasi dan penggunaan aplikasi pembuatan video telah dilakukan ke 45 orang Guru SMP-SMA Muhammadiyah Gresik pada tanggal 21 Juni 2022 untuk meningkatkan kompetensi guru terhadap pemanfaatan teknologi digital dalam pembelajaran. Metode pelaksanaan kegiatan meliputi pemberian materi oleh tenaga ahli, praktik peserta didampingi oleh mentor, dan pembuatan video secara mandiri. Berdasar hasil analisis nilai pre-test dan post-test saat kegiatan, terdapat peningkatan nilai peserta dari sebelum pelatihan (pre-test) adalah 76,8 dan setelah mengikuti pelatihan (post-test), nilai peserta menjadi 97,2. Peserta mendapatkan peningkatan pemahaman dalam membuat video pembelajaran yang ditunjukkan dengan hasil karya video pembelajaran yang dibuat secara individu oleh peserta. Video pembelajaran yang dihasilkan peserta juga telah memenuhi kriteria video digital yang baik. Data evaluasi kegiatan menunjukkan workshop ini diperlukan dan tepat sasaran untuk pengembangan profesional khususnya Guru SMP-SMA Muhammadiyah Gresik. Konsep kegiatan juga sesuai untuk menyelesaikan permasalahan yang ada di pendidikan tingkat SMP-SMA. Dengan demikian, pelatihan ini berhasil meningkatkan kompetensi peserta tentang penggunaan video dan teknologi digital sebagai salah satu inovasi pembelajaran.Teachers are responsible for ensuring students catch on to the subject matter. However, the limited study time in class and students' varying abilities cause face-to-face learning methods to be less effective in increasing student understanding. The global challenge of education demands teachers become competent in digital mastering technology. Learning videos that are presented virtually are an effective learning method for students. Consequently, teachers should have the ability to make digital videos independently. This study introduced digital technology types, installation, and video-making applications for teachers in Muhammadiyah's junior and senior high schools in Gresik (SMP-SMA Muhammadiyah Gresik) on June 21, 2022, increasing teacher competency in using digital technology in learning. The implementation method includes providing material by experts, having participants practice accompanied by mentors, and making videos independently. Based on the analysis of the pre-test and post-test scores during the activity, there was an increase in the participant's score from before the training (pre-test), which was 76.8. After participating in the training (post-test), the participant scored 97.2. Participants gain an increased understanding of making learning videos, as shown by the results of learning videos made individually by participants. The learning videos produced by the participants also met the criteria for good digital videos. Activity evaluation data show that this workshop is necessary and right on target for professional development, especially for SMP-SMA Muhammadiyah Gresik Teachers. The activity concept is also suitable for solving problems in junior high school level education. Thus, this training succeeded in increasing the competence of participants regarding the use of video and digital technology as one of the learning innovations.

Direct Synthesis of Highly Crystalline ZSM-5 from Indonesian Kaolin Hartati Hartati; Alfa Akustia Widati; Tanti Kartika Dewi; Didik Prasetyoko
Bulletin of Chemical Reaction Engineering & Catalysis 2017: BCREC Volume 12 Issue 2 Year 2017 (August 2017)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.12.2.809.251-255

Co-Authors A. Budi Prasetyo Abdulloh Abdulloh AFAF BAKTIR Ahlan Riwahyu Habibi Ahmadi Jaya Permana Aisyah Aisyah Alfinda Novi Kristanti Ali Rohman Alviani, Ziana Anik Fathur Rohmah Aning Purwaningsih Atik Widiyanti Aulianitha Salsabella Bahrotul Ilmiah Bambang Rusdiarso Budi Prasetyo, Antonius Dessy Puspa Aryanti Didik Prasetyoko Eko Sri Kunarti Faiz Tamamy Fatiha Khairunnisa Ganden Supriyanto Handoko Darmokoesoemo Harsasi Setyawati Hartati Hartati Hartati Hartati Hartati Hartati Hwei Voon, Lee ILHAMI, MUHAMMAD HAEKAL NUR Imam Siswanto Indriana Kartini Irene Dinda Oktavia Kariza Makanty Madjid Arie Wibowo Miratul Khasanah Mochamad Zakki Fahmi Muji Harsini Musbahu Adam Ahmad Nanik Siti Aminah Ni Nyoman Tri Puspaningsih Nuryono Nuryono Oktaviana, Citra Marantika Nur Purkan Purkan Purkan Purkan, Purkan Purwaningsih, Aning Puspitasari, Evrillia Qurrota A’yuni Rahmawati, Zeni Rico Ramadhan, Rico Rochadi Prasetya Salsabilah, Andina Fitriyah Satya Candra Wibawa Sakti Severia, Nadya Maya Siti Wafiroh Sofijan Hadi Sri Sumarsih Tanti Kartika Dewi Tokok Adiarto Tokok Ardiarto Ulfa Rahmah Ummah, Naftalia Wirdatul Usreg Sri Handajani WAHYUNI, SITI NUR Wan Abdullah, Wan Nazwanie Yanuardi Raharjo, Yanuardi

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