Sintesis dan Karakterisasi Fasa Crystoballite Berbasis Silika Sekam Padi dengan Metode Sintering (Solid State)

This study was carried out to characterize the formation of crystoballite crystall of silica extracted from rice husk by sintering. Extraction of silica using 5% KOH and 10% HCl solution was sintered at 750, 900, 1000,and 1100 C. The products were characterised in term of functional groups, microstructure and structure (FTIR, SEM and XRD). Characterisation of the silica using FTIR shows the presence of silanol and siloxane. XRD results confirmed that silica amorph was formed at 750C, through the intermediate formation of crystoballite 900, 1000, and 1100C. The formation of crystoballite structure increases with increasing temperature of sintering, which confirms the presence of regular particle size using SEM analysis.Keywords: Rice Husk, Silica, Crystoballite, FTIR, SEM and XR

Coal Ash Characteristic from Bukit Asam as Raw Material for Ceramics Production

This study was carried out to characterize coal ash obtained from Bukit Asam, Tarahan Lampung, after the samples were sintered at various temperatures ranging from 900C - 1300C. The characteristics of the investigated samples included density, porosity, hardness, structure and microstructure. The results indicated that porosity decreased with increasing sintering temperature, while density and hardness increased with increasing temperature. The x-ray diffraction (XRD) study revealed that the main crystalline phase was silicon dioxide (SiO2), with the minor constituents of CaSiO2, MgSiO3, FeSiO4 and Ca12Al14O33. SEM investigations clearly demonstrated the presence of a fine crystallised phase dispersed in the microstructure

Pengaruh Suhu Tinggi terhadap Karakteristik Keramik Cordierite Berbasis Silika Sekam Padi

This study was carried out to investigate the effect of high temperature on the functional groups, microstructure and physical characteristics of cordierite ceramics obtained from an aqueous solution of magnesium nitrate hydrate ((Mg(NO3)2.6.12H2O)), aluminium nitrate hydrate (Al(NO3)2.9.15H2O) and silica sols extracted from rice husk. The samples were sintered at temperature of 1000◦C, 1200◦C and 1400◦C. Functional groups and microstructural characteristics of cordierite ceramics were examined by FTIR and SEM, respectivelly. FTIR study shows that the absence of the vibration bands of Na-OH, Si-OH, C-O, Si-O-Si on the samples. However, the formation of cordierite structure was dominated on this high temperature. Microstructure results confirmed the presence of irregular morphology of the solid and compact phases. In addition, the densities, shrinkage andhardness of cordierite increase significantly with increasing temperature, but porosity decreases with increasingtemperature

Selective Reduction of High Alumina-Lateritic Nickel Ore (0.5 Ni-44Fe-16Al2O3)

In this present study, the effect of reductant dosage, temperature and holding time on selective reduction process of high alumina-lateritic nickel ore have been investigated clearly. The lateritic nickel ore was reduced with 5 until 15 wt. % anthracite and 10 wt. % sodium sulfate at reduction temperature of 950ºC, 1050ºC and 1150°C for 60, 90, and 120 minutes. Magnetic separation process was then conducted to separate the concentrate and tailing. The analysis of reduced nickel ore is performed by the Atomic Absorption Spectroscopy, X-Ray Diffraction, and Secondary Electron Microscopy. The optimal process resulted from the reduction of nickel ore with 10 wt. % anthracite at the temperature of 1050°C for 120 minutes which resulted in 0.84% nickel in concentrate. The troilite was not found in reduced ore. The iron grade increased along the increased of reduction temperature. The longer of holding time in selective reduction process increased the nickel grade but it decreased the iron grade

Edukasi dan Pendampingan Pembuatan Hand Sanitizer Berbasis Ekstrak Daun Sirih Piper Betle L.

ABSTRAK Kegiatan Pengabdian kepada Masyarakat ini merupakan bentuk pengemnagnag dalam memanfaatkan daun sirih sebagai hand sanitizer. Kegiatan ini bertempat si Desa Hajimena Kecamatan Natar Lampung Selatan dengan jumlah peserta 33 orang. Daun sirih banyak dijumpai di pekarangan rumah warga dan potensi sebagai antiseptik namun belum dimanfaatkan dengan baik dan budaya cuci tangan dengan baik dan benar sesuai anjuran WHO masih kurang. Permasalahan tersebut mendorong untuk membina masyarakat guna mengelola potensi daun sirih sebagai salah satu tanaman obat keluarga yang dapat dimanfaatkan potensinya untuk pencegahan penyebaran Covid-19 dan memberikan edukasi serta bimbingan teknis untuk membuat hand sanitizer dari ekstrak dauh sirih dikombinasikan dengan formula World Health Organization (WHO) dengan menerapkan teknik yang sederhana sehingga warga dapat mengolahnya secara mandiri, hasilnya masyarakat telah mampu membuat hand sanitizer sendiri, serta bisa mencuci tangah dengan baik dan benar, didukung dengan terjadi peningkatan pencapaian TIK sebelum kegiatan pengabdian adalah 37,67 %. Kemudian, setelah diadakan kegiatan pengabdian terjadi peningkatan pencapaian TIK menjadi 82,32 %. Hal ini menunjukkan bahwa terjadi peningkatan pengetahuan masyarakat tentang pembuatan hand sanitizer berbasis ekstrak daun sirih. Kata kunci: Daun sirih, Hand Sanitizer, Covid-19, World Health Organization  ABSTRACT Pengabdian kepada Masyarakat activity is a form of development in utilizing betel leaf as a hand sanitizer. This activity took place in Hajimena Village, Natar District, South Lampung with 33 participants. Betel leaves are often found in people's yards and have potential as an antiseptic but have not been used properly and the culture of washing hands properly and correctly according to WHO recommendations is still lacking. These problems encourage the community to manage the potential of betel leaf as one of the family medicinal plants whose potential can be utilized to prevent the spread of Covid-19 and provide education and technical guidance to make hand sanitizers from betel leaf extract combined with the World Health Organization (WHO) formula. by applying a simple technique so that residents can process it independently, the result is that the community has been able to make their own hand sanitizer, and can wash their hands properly and correctly, supported by an increase in ICT achievement before service activities was 37.67%. Then, after the service activities were held, there was an increase in ICT achievement to 82.32%. This shows that there is an increase in public knowledge about the manufacture of hand sanitizers based on betel leaf extract.  Keywords: Betle Leaf, Hand Sanitizer, Covid-19, World Health Organizatio

Efek Penambahan Fe3Mn7 Terhadap Sifat Fisis dan Mekanik α-Fe2O3

Abstrak: Preparasi dan karakterisasi pellet α-Fe2O3 dengan penambahan 0, 2, 5 dan 10 %wt. Fe3Mn7 berbasis pada materialalam telah berhasil dilakukan. Proses pencampuran serbuk α-Fe2O3 dan Fe3Mn7 dilakukan dengan menggunakan HEM. ºKemudian campuran serbuk dikasinasi pada suhu 1000C, dikompaksi pada 69 Pa hingga menjadi pellet dan disinter padasuhu 1000 ºC. Karakterisasi XRD menunjukkan adanya fasa dominan α-Fe2O3 dan fasa baru MnO2 dan Fe3O4. Densitas dankekerasan sampel meningkat secara linier seiring dengan kenaikan komposisi Fe3Mn7 yang ditambahkan. Sampel optimum3diperoleh pada sampel α-Fe2O3/10 %wt. Fe3Mn7 dengan nilai bulk density dan kekerasan masing-masing 4,98 g/cm and994,94 HV. Sampel ini termasuk dalam klasifikasi hard magnet dengan nilai magnetisasi saturasi, remanen dan koersivitasmasing-masing sebesar 24,0 emu/g, 10,3 emu/g dan 571,8 Oe.Kata kunci:. α-Fe2O3, Fe3Mn7, densitas, kekerasan, sifat magnetikAbstract: Preparation and characterization of α-Fe2O3 pellet with the addition of 0, 2, 5 and 10 %wt. Fe3Mn7 based on naturalmaterials have been successfully carried out. The process of mixing powder of α-Fe2O3 and Fe3Mn7 was performed usingºHEM. Then, the mix powders were calcined at temperature of 1000 C. After that, the powders were compacted at 69 Pa intopellet and sintered at temperature of 1000ºC. Characterization of XRD shows that the samples have major phase of α-Fe2O3and new phases of MnO2 and Fe3O4. The density and hardness samples increase linearly with increasing of Fe3Mn73composition. The optimum sample with α-Fe2O3/10 %wt. Fe3Mn7 has bulk density and hardness value of 4.98 g/cm and 994.94HV respectively. This sample is classified as semi-hard magnet with magnetization saturation, remanence and coercivity valueof 24.0 emu/g, 10.3 emu/g dan 571.8 Oe respectively.Keywords: α-Fe2O3, Fe3Mn7, density, hardness, magnetic propertie

Pendampingan Pengelolaan Website Desa Hajimena sebagai Penunjang Program Digitalisasi Desa

ABSTRAK Desa Hajimena merupakan salah satu desa yang berada di Kecamatan Natar Lampung Selatan. Infrastruktur fasilitas umum dan pendidikan sudah sangat memadai untuk memenuhi kebutuhan dasar dan pendidikan masyarakat setempat. Kelengkapan infrastuktur yang ada di desa hajimena belum didukung oleh perkembangan sistem informasi yang memadai salah satunya adalah media informasi desa berbasis website. Media informasi desa sangat diperlukan untuk mengikuti perkembangan teknologi informasi yang sangat pesat, dewasa ini tuntutan terhadap sistem informasi berbasis komputer dan internet hampir di segala bidang, baik pemerintahan, industri, bisnis pendidikan, dan bidang lainnya. Permasalahan tersebut mendorong untuk membuat sekaligus membina perangkat desa untuk mengelola website Desa sebagai sarana informasi digital yang di dalamnya terdapat layanan administrasi desa, pelayanan desa, dan profil desa. Metode yanga digunakan pada kegiatan pengabdian kepada masyarakat menggunakan teknik ceramah, praktik, dan diskusi. Hasilnya kegiatan pengabdian yang telah dilakukan, masyarakat mampu memahami terkait pengelolaan website khususnya adalah operator desa, hal ini didukung dengan terjadi peningkatan pencapaian TIK sebesar 83,5% yang sebelum kegiatan pengabdian yaitu 41,83 %. Hal ini menunjukkan bahwa terjadi peningkatan pengetahuan dan kemampuan masyarakat tentang pengelolaan website Desa. Kata Kunci: Hajimena, Layanan, Informasi Digital, Website Desa,   ABSTRACT Hajimena Village is one of the villages in Natar District, South Lampung. The infrastructure of public facilities and education is very adequate to meet the basic needs and education of the local community. The completeness of the existing infrastructure in the Hajimena village has not been supported by the development of sufficient information systems, one of which is the website-based village information media. Village information media is very necessary to keep up with the very rapid information technology, this development of computer and internet-based information systems in almost all fields, be it government, industry, business, education, and other fields. This problem encourages the creation and development of village officials to manage the Village website as a means of digital information in which there are village administration services, village services, and village profiles. The method used in community service activities uses lecture, practice, and discussion techniques .The results of the service carried out, the community is able to understand the management of the website, especially village operators, this is supported by an increase in ICT by 83.5% before service activities, which is 41.83%. This shows that there is an increase in community knowledge and ability about managing the Village website. Keywords: Hajimena, Service, Digital Information, Village Website

Effect of alumina addition on the phase transformation and crystallisation properties of refractory cordierite prepared from amorphous rice husk silica

The effect of alumina addition of 5–30% by weight on phase transformation and crystallisation properties of refractory cordierite ceramics prepared from amorphous rice husk silica followed by sintering treatment at temperature of 1230 °C was studied. The crystallinity and microstructure of the samples were characterised using X-ray diffraction (XRD) coupled with Rietveld analysis, scanning electron microscopy (SEM), respectively. Some physical properties include density, porosity, hardness, bending strength, and thermal expansion coefficient of the samples with different alumina additions were measured. The results show that addition of alumina promoted crystallisation of cordierite into crystalline spinel, corundum, cristobalite, in which with addition of 10–30% alumina, the cordierite phase was practically undetected. Addition of alumina was also found to increase the amount of spinel, while corundum and cristobalite decreased following alumina addition of 10–30%. The presence of spinel, corundum, and cristobalite resulted in increased of density, hardness, bending strength and thermal expansion coefficient, while for porosity, the opposite was observed. Thermal expansion coefficient of the samples with alumina addition of 15–30% reach the relatively constant value of 9.5 × 10−6/°C, with the main crystalline phase was spinel, accompanied by corundum and cristobalite in smaller quantities

PREPARATION OF SILVER DOPED RICE HUSK SILICA COMPOSITES USING SOL GEL METHOD

Composites of silver-doped rice husk silica using sol-gel method has been conducted. Silver nitrate and rice husks were used as resources. Composites were sintered at 850°C and then characterized using Infrared Spectrophotometer (FTIR), x-ray diffractometer (XRD) coupled with Rietveld analysis, Electron Microscope (SEM/EDS), Ultraviolet-visible (UV-vis) spectroscopy and The Brunauer-Emmett-Teller (BET) methods. Results obtained indicate significant role of Ag concentration and that phase transformation changed samples characteristics, including increased crystallite size and absorbance. Results also showed that Ag/SiO₂ composite with uniform microstructure in the form of spherical particles of Ag with relatively uniform size which were dominated by silver and cristobalite phases as the main phases. Meanwhile, silver phase emerged as a dominant phase and was embedded in a silica matrix. The crystal sizes of silver and cristobalite were found to be 40 and 20 nm, respectively. Absorbance value showed that Ag/SiO₂ work on two wavelengths of 310 and 415 nm. Surface area values obtained range from 5.0-11.4 m²/g that belongs to the mesopores criteria. Such structural and textural properties of the produced composite indicate its suitability to be used as catalyst

Selective Reduction of High Alumina-Lateritic Nickel Ore (0.5 Ni-44Fe-16Al2O3)

In this present study, the effect of reductant dosage, temperature and holding time on selective reduction process of high alumina-lateritic nickel ore have been investigated clearly. The lateritic nickel ore was reduced with 5 until 15 wt. % anthracite and 10 wt. % sodium sulfate at reduction temperature of 950ºC, 1050ºC and 1150°C for 60, 90, and 120 minutes. Magnetic separation process was then conducted to separate the concentrate and tailing. The analysis of reduced nickel ore is performed by the Atomic Absorption Spectroscopy, X-Ray Diffraction, and Secondary Electron Microscopy. The optimal process resulted from the reduction of nickel ore with 10 wt. % anthracite at the temperature of 1050°C for 120 minutes which resulted in 0.84% nickel in concentrate. The troilite was not found in reduced ore. The iron grade increased along the increased of reduction temperature. The longer of holding time in selective reduction process increased the nickel grade but it decreased the iron grade