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Deactivation and Regeneration of Ni/ZA Catalyst in Hydrocracking of Polypropylene Imam Khabib; Sri Kadarwati; Sri Wahyuni
Indonesian Journal of Chemistry Vol 14, No 2 (2014)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (294.149 KB) | DOI: 10.22146/ijc.21258

Abstract

The phenomena of catalyst deactivation and the effects of regeneration method on the characteristics and activity of Ni/ZA catalyst after being used in a continuous cracking reaction of polypropylene have been studied. Ni/ZA catalyst was prepared using sonochemical method with total metal intake of 4%. Characteristics and activity of fresh, spent, and regenerated catalyst were evaluated to get a better understanding about the catalyst deactivation. Characteristics which have been observed include catalyst acidity, porosity, crystallinity, and surface morphology. Catalytic activity test of Ni/ZA catalyst on polypropylene cracking reaction at temperature of 500 °C with H2 flow rate of 20 mL/min and catalyst:feed ratio of 1:2 (w/w) showed the decrease of some catalyst characteristics such as specific surface area, total pore volume, and acidity due to coke fouling over a five-times continuous experiment. Regeneration of catalyst with oxidation-reduction method has been able to increase the activity and acidity of catalyst up to 7.47% and 38.54%, respectively, compared to those of spent catalyst, while the catalyst surface area and total pore volume decreased up to 32.83% and 26.92%, respectively.
Kinetics and Mechanism of Ni/Zeolite-Catalyzed Hydrocracking of Palm Oil into Bio-Fuel Sri Kadarwati; Fitri Rahmawati; Puji Eka Rahayu; Kasmadi Imam Supardi
Indonesian Journal of Chemistry Vol 13, No 1 (2013)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2008.618 KB) | DOI: 10.22146/ijc.21330

Abstract

Kinetics and mechanisms of Ni/zeolite-catalyzed cracking reaction of methyl ester palm oil (MEPO) were studied using a continuous flow-fixed bed reactor system at an atmospheric pressure. The catalyst was prepared by wet impregnation method with a solution of nickel nitrate hexahydrate as the precursor and zeolite as carrier. The characteristics of catalyst including active Ni metal content, crystallinity, total acidity, and porosity were evaluated. The reactions were performed with a varied hydrogen flow rate as a carrier gas as well as a reductant and reaction time. Liquid products were analyzed by GC. Analysis by GC-MS was only conducted on a product at hydrogen flow rate with the best conversion. It has been shown that the catalyst has a superior character for hydrocracking reactions of MEPO into green fuel. No considerable effect of hydrogen flow rate on the total conversion was observed. The tests showed that the kinetics of Ni/zeolite-catalyzed cracking reaction followed pseudo-first order kinetics. GC-MS analysis revealed the formation of light hydrocarbon products with C6-C8 of aliphatic and cyclic components without oxygenates. Distribution of the product indicated that the cracking reaction as well as the isomerization of the products of hydrocracking occurred. Thus, Ni/zeolite-catalyzed cracking involved cracking /hydrogenation, isomerization, cyclization, and deoxygenation.
PREPARATION, CHARACTERIZATION, AND CATALYTIC ACTIVITY TEST OF Ni-Mo/NATURAL ZEOLITE ON PYRIDINE HYDRODENITROGENATION Sri Kadarwati; Sri Wahyuni; Wega Trisunaryanti; Triyono Triyono
Indonesian Journal of Chemistry Vol 10, No 3 (2010)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (183.929 KB) | DOI: 10.22146/ijc.21438

Abstract

Preparation, characterization, and catalytic activity test of Ni-Mo/natural zeolite on pyridine hydrodenitrogenation were carried out. Preparation of catalyst was conducted by impregnation method using nickel nitrate hexahydrate and ammonium heptamolibdate precursor as Ni and Mo source respectively. Characterization of catalyst was conducted by using gravimetry, atomic absorption spectrophotometry, and X-ray diffraction method. Catalytic activity test on pyridine hydrodenitrogenation was carried out by using flow system reactor with hydrogen flow rate variable. The research results showed that the catalyst's total acidity and crystallinity are increased with level of impregnation success of 96.71% and 90.08% respectively. Ni-Mo/natural zeolites able to increase the catalytic conversion up to 71.78% at 350 °C and hydrogen flow rate of 10 mL/min with more highly varied product distribution. Assuming that the pyridine hydrodenitrogenation follows the pseudo first order kinetics.
Persepsi dan Kesiapan Guru dalam Menghadapi Asesmen Kompetensi Minimum Nurhikmah Nurhikmah; Isti Hidayah; Sri Kadarwati
Cokroaminoto Journal of Primary Education Vol. 4 No. 1 (2021): April 2021
Publisher : Universitas Cokroaminoto Palopo

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30605/cjpe.412021.1294

Abstract

Penelitian ini bertujuan untuk mengetahui persepsi guru dalam menghadapi AKM tahun 2021 dan untuk mengetahui kesiapan dalam menghadapi AKM. Penelitian ini mengguanakn metode deskriptif. Teknik pengumpulan data yang dilakukan dalam penelitian ini adalah observasi, wawancara dan dokumentasi. Penelitian ini dilaksanakan di SD 23 Batara Kota Palopo. Penelitian dilakukan di SD 23 Batara didasarkan atas informasi bahwa guru bahwa pernah mengikuti pertemuan tentang pembahasan AKM di Kota Palopo. Hasil penelitian menunjukan bahwa guru sudah memahami AKM dilihat dari kemampuan guru membuat komponen-komponen dalam penyusunannya. Kesiapan guru juga sudah cukup dalam menghadapi AKM tahun 2021
Performance of HDTMA-Br-Modified Indonesian Zeolite as a Drug Carrier Candidate for Diclofenac Sodium Khafidhotun Naimah; Harjono Harjono; Jumaeri Jumaeri; Sri Kadarwati
Jurnal Kimia Sains dan Aplikasi Vol 24, No 3 (2021): Volume 24 Issue 3 Year 2021
Publisher : Chemistry Department, Faculty of Sciences and Mathematics, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (4104.288 KB) | DOI: 10.14710/jksa.24.3.91-100

Abstract

Diclofenac sodium is a non-steroidal anti-inflammatory drug with a relatively short release time. This short release time promotes a more frequent drug consumption and could lead to side effects in the stomach, e.g., gastrointestinal disorders, gastrointestinal bleeding, and gastric ulcers. A drug delivery system with a slow-release activity is one of the promising technologies to control the drug amount released to the stomach. A surfactant-modified natural zeolite as a carrier for diclofenac sodium has been used in this study. This study focused on the preparation, characterization, and slow-release performance of HDTMA-modified natural zeolite as a carrier for diclofenac sodium. The zeolite underwent chemical and physical activation, as well as milling prior to use. It was proven that the zeolite used was dominated by mordenite and clinoptilolite with high stability properties towards acid treatments, as indicated by the XRD patterns. A modification of the zeolite surface using HDTMABr was also successfully performed, indicated by the appearance of peaks at wavenumbers of 2923.05 cm-1 and 2853.39 cm-1 (symmetrical and asymmetrical CH2 strains of HDTMA molecules, respectively) in the FTIR spectra. The synthesized HDTMA-modified natural zeolite also showed an excellent surface property such as surface area, pore-volume, and size, as indicated by the BET-BJH isotherms on the nitrogen adsorption. The slow-release performance of the zeolite-based drug delivery system was studied by investigating the adsorption-desorption behavior of HDTMA-modified zeolite towards diclofenac sodium. The HDTMA-modified zeolite adsorbed the diclofenac sodium of 54.01% at a pH of 7.5, the contact time of 60 min, and the initial concentration of 100 ppm. The adsorbed diclofenac sodium of 73.95% could be released from the HDTMA-modified adsorbent for 8 h, mimicking the time length of drug metabolism in the human body.
PENINGKATAN KEMAMPUAN GURU-GURU KIMIA KABUPATEN KENDAL DALAM MENDESAIN PENELITIAN TINDAKAN KELAS Saptorini Saptorini; A Tri Widodo; Sri Kadarwati
Jurnal Penelitian Pendidikan Vol 30, No 2 (2013): October 2013
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/jpp.v30i2.5674

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The results of preliminary study showed that chemistry teachers in Kendal didn’t know how to design CAR, has not been able to integrate models, strategies, and approaches of learning to certain topics to design CAR, and find the time management difficult in CAR. Thus, it was needed to train them the basic skills to teach so they will be able to design and conduct a CAR that will give a direct impact on the quality instuction in the classroom. This activity was carried out in two main phases, namely seminar and workshop in stage I and mentoring of CAR preparation in stage II. The results of this activity indicated that CAR preparation training for chemistry teachers in Kendal was be able to improve chemistry teachers’ capability in developing CAR. However, an increase in teachers’ character as a figure, in addition to increasing the professionalism of teachers who simply boils down to the academic side is still needed. In addition, the school and the Education Department needs to provide more facilities for the implementation of CAR in school continue to increase the sustainaible quality of the learning process.
Penggunaan Limbah Air Cucian Beras sebagai Bahan Dasar Pembuatan POC (Pupuk Organik Cair) Di Desa Ngabeyan Kecamatan Candiroto Kabupaten Temanggung Adinda Hapsari; M Rafi Antoni; Try Astuti; Putriana Dewi; Sri Kadarwati
Jurnal Bina Desa Vol 5, No 2 (2023) : Juni
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/jbd.v5i2.41460

Abstract

Terdapat berbagai limbah rumah tangga yang ada di sekitar kita dan dapat dimanfaatkan menjadi pupuk organik salah satunya adalah limbah air cucian beras. Setiap proses menanak nasi setiap harinya menghasilkan banyak limbah air cucian beras. Dalam hal tersebut mahasiswa memiliki tujuan untuk melakukan terobosan baru dengan menggunakan limbah air beras sebagai pupuk organik cair karena tingginya intensitas penggunaan pestisida serta pupuk anorganik di Desa Ngabeyan dikhawatirkan mencemari lingkungan dan memiliki efek samping. Maka dari itu, mahasiswa KKN UNNES GIAT 3 Desa Ngabeyan memberikan informasi dan sosialisasi pembuatan Pupuk Organik Cair (POC) kepada Kelompok Wanita Tani (KWT) Desa Ngabeyan. Hasil dari sosialisasi pemanfaatan pupuk organik cair, anggota KWT dapat memproduksi sendiri maupun dijual sebagai produk UMKM. Saran untuk pemanfaatan pupuk organik cair dapat dilakukan pada skala besar sehingga pupuk organik cair tersebut dapat bernilai ekonomis. Serta adanya penelitian tersebut diharapkan dapat mengurangi penggunaan pupuk anorganik yang dapat membahayakan lingkungan.
Fun and Exciting Research in Competitive Research Design Kadarwati, Sri; Sumarni, Woro; Wijaya, Atika; Alauhdin, Mohammad; Kurniawan, Cepi; Huda, Nuril; Budiyanto, Teguh; Pramestia, Rena Aliya; Azzahra, Elvara Siti
Jurnal Abdimas Vol 27, No 2 (2023): December 2023
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/abdimas.v27i2.48396

Abstract

Research involving high school students or equivalent has been in great demand in recent years. Various ministries , government institutions and universities have launched various competitive research programs and events competition based research for SMA/MA level. Students and teachers at MAN 1 Semarang City have so far experienced many difficulties in designing competitive research. The achievements made by MAN 1 Semarang City students in the field of research are still very limited. The limited research experience of accompanying teachers could also be one of the causes. Collaboration with universities as institutions that not only provide education and teaching, but also research development, is a must. Therefore, assistance in designing research that is worthy of being competed in prestigious research competitions by the Semarang State University community service team is very important. Mentoring activities are carried out in the fields of science, technology and social humanities, involving Semarang State University research experts from both fields of study. This activity involved 31 students from MAN 1 Semarang City who were members of the madrasa research program along with 9 research assistant teachers from various fields of science. Activities include assistance in several phases of competitive research design, namely creating research ideas, drafting and finalizing research designs. This activity received a very good response and was seen as being able to help students and research assistant teachers at MAN 1 Semarang City in generating brilliant research ideas with novelty or novelty and high usefulness for the advancement of science and technology. A total of three proposal titles were produced from this activity ; one title in the field of social and human affairs and two titles in the field of science and technology. The obstacles in implementing mentoring are felt by teachers and students who have to spare time between busy teaching and learning activities at madrasas. The implementing team expressed its appreciation to the research supervisors and students who had successfully prepared research proposals to the final stage.
Unpaid Application-Based Learning Video Production with Teachers Harjito, Harjito; Kadarwati, Sri; Nuswowati, Murbangun; Kasmui, Kasmui; Asmorowati, Dian Sri; Mubarak, Dinda Halimah Agrifani; Damayanti, Yosephine Debbie; Rohmah, Rojaa Maysa
Jurnal Abdimas Vol 27, No 2 (2023): December 2023
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/abdimas.v27i2.44321

Abstract

Students at SMA Negeri 1 Subah, Batang Regency, Central Java, in the post-pandemic era , need auxiliary media that can be widely accessed , are timeless , and are needed to support face-to-face learning in class, such as learning videos . Auxiliary media This can developed and produced alone by the teacher without must relying on digital platforms such as YouTube. However, only a small number of teachers at SMA Negeri I Subah have been able to develop and produce learning videos. Because yes , activities This aim For accompany all the teachers subjects at SMA Negeri 1 Subah for develop and produce learning videos through systematic and comprehensive steps. This activity includes several important stages, namely: (1) recognizing and compiling learning video scripts, (2) practicing the basics of Open Broadcaster Software (OBS), (3) producing videos based on scripts, (4) modifying learning videos into interactive videos using H5P, and (5) dissemination of results. This activity ends with an assessment and evaluation of the learning videos produced at the end of the activity and the overall implementation of the activity. The results of this activity show that the number of teachers is capable develop and produce learning videos experience improvement , though Not yet significant . Learning videos produced by teachers have been fulfil terms , though Still need improved the quality . Motivation and support from schools and parties related need improved so that teachers continue enthusiastic produce quality learning video products.
Environmentally Oriented Chemistry Practical Worksheets to Improve Conservation Character and Environmental Literacy Nuswowati, Murbangun; Kadarwati, Sri; Susatyo, Eko Budi; Huda, Nuril; Kolilah, Liluk; Dewi, Silmi Dalila Millatina; Zahro, Ainu Ilmiatuz; Azzahra, Yasmin
Jurnal Abdimas Vol 27, No 2 (2023): December 2023
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/abdimas.v27i2.47382

Abstract

Management of chemistry practicum implementation has become a problem center that must be faced. This is caused by limited equipment and materials available in the laboratory, shortage of laboratory personnel , as well as its height costs required to carry out the practicum. Apart from that, chemistry practicum requires a high level of creativity from Chemistry teachers, well when they have to organize practicums independently and in classical learning for students. Therefore , guidance and mentoring _ from the service team is very important to help Chemistry teachers in developing their learning materials. This assistance takes place from June 22 to August 16 2022, starting with coordination between chairman of the MA Chemistry MGMP with the UNNES service team. The aim of the Community Service Program (PPM) is to build conservation character and environmental literacy among Chemistry teachers, also involving students, and of course MA students in Semarang. To date, there have been 2 environmentally oriented Chemistry Practical Worksheets created successfully , which is the result collaboration between one teacher and one student. At the end of August, we will proceed with further implementation steps . Results _ from this service activity will be published in a national journal accredited SINTA 3-6 . The process of writing the publication is ongoing, as are the manuscripts that will be published published through mass media . Devotion team firmly underlines the cultural importance of implementing environmentally oriented Chemistry Practical Worksheets that use the potential of natural materials available around the home.
Co-Authors - Jumaeri A Tri Widodo A Tri Widodo Adinda Hapsari Aditia Nur Bakti Agung Feinnudin Amalina, Nur Dina Anggreani, Ina Annisa, Riska Nurfirda Aprillia Findayani Arma Yoga Astutik, Kasni Atika Wijaya Ayu Nugrahantia, Ayu Azzahra, Elvara Siti Azzahra, Yasmin Bahij, Aida Tika Biluthfil Bakti, Prayoga Bangun Yulianto Cepi Kurniawan Damayanti, Kristina Damayanti, Lutfia Damayanti, Yosephine Debbie Dewi, Silmi Dalila Millatina Dhian Ekowati Dian Sri Asmorowati Edi Prayitno, Edi Edy Cahyono Eko Budi Susatyo Elsa Ari Astuti Endang Susilaningsih Evalisa Apriliani, Evalisa Evita H. Legowo Fitri Rahmawati Fitri Rahmawati Harjito - Harjito Harjito Hidayah, Aida Nur Hutomo Wahyu Nugroho I Ketut Suada Imam Khabib Imam Kusmaryono Indriana Kartini Isti Hidayah Iswanto, Haifa Firyal Joseph P. Brinkman Junaid Sadrach Kartikasari, Reny Kasmadi Imam Supardi Kasmui -, Kasmui Khaerur Rifqi, Khaerur Khafidhotun Naimah Kolilah, Liluk Lailatul Badriyah Latifah Latifah LENI HERLINA Luluk Amnah Fitriyana, Luluk Amnah M Rafi Antoni M. Udiharto Malik, Septina Praditia Marcelino, Richie Mohammad Alauhdin, Mohammad Mubarak, Dinda Halimah Agrifani Muflikah, Binti Murbangun Nuswowati Nila Ubaidah Noegroho Hadi NOEGROHO HADI HS Noegroho Hadi HS. Nuhyal Ulya Nurhikmah Nurhikmah Nuril Huda Nurul Fadhilah Pertiwi Ayu Pamuji Kurniatun, Pertiwi Ayu Pamuji Pramestia, Rena Aliya Prima Astuti Handayani Puji Eka Rahayu Puji Eka Rahayu Putriana Dewi Rahayu, Sri Astusi Rani, Devitra Saka Rida Farida, Rida Risna Anggraeni Rohmah, Rojaa Maysa Rudiyanto, Aris Rudiyanto, Aris Sadrach, Junaid Saptorini Saptorini Saptorini Saptorini, Saptorini Siddiq Wahyu Hidayat Sigit Priatmoko Soeprodio Soeprodio, Soeprodio Soeprodjo Soeprodjo, Soeprodjo Sri Astusi Rahayu Sri Susilogati Sumarti Sri Wahyuni Sri Wahyuni Sri Wahyuni SRI WARDANI Subiyanto Hadi Saputro Sugihardjo Sugihardjo Sugihardjo Sugihardjo Sulistyaningsih, Nining Sulistyarini, Ika Teguh Budiyanto, Teguh Triyono Triyono Try Astuti Wandah Wibawanto Wara Dyah Pita Rengga Wega Trisunaryanti Witono Basuki, Witono Woro Sumarni Wuwus Ardiatna Zahro, Ainu Ilmiatuz