Computational study of green production of Vanilli Planifolia based Schiff Base using ionic liquid solvent

Basa Schiff adalah produk kondensasi dari senyawa amina primer seperti anisidina dengan senyawa karboksilat yang memiliki banyak kegunaan di bidang kimia. Untuk menaikkan nilai tambah produk lokal, senyawa dari tanaman Vanilli Planifolia dapat digunakan sebagai sumber gugus karboksilat. Sintesis secara konvensional memiliki banyak kekurangan semisal yield yang kecil dan limbah yang berbahaya bagi lingkungan. Berdasarkan hal tersebut, perlu dilakukan modifikasi reaksi untuk mengurangi dampak berbahayanya seperti dengan menggunakan cairan ion. Metode komputasi digunakan dalam riset dasar ini karena dapat mengurangi waktu dan biaya riset. Dari hasil dari perhitungan komputasi, didapatkan bahwa penambahan pelarut terbukti dapat memberikan efek penstabilan pada semua molekul terutama bila memiliki sifat kepolaran sejenis. Reaksi produksi basa Schiff terjadi dalam keadaan endoterm dan tidak spontan di suhu kamar. Reaksi tersebut melewati tiga tahap reaksi dengan tahapan penentu laju terjadi pada tahap ke-3. Energi pengaktifan ditemukan lebih kecil pada pelarut cairan ion dari pada pelarut polar lain. Pada tahap reaksi pertama, energi pengaktifan paling minimum ditemukan pada pelarut [EMIM][TfO] sebesar 119.915 kJ.mol-1. Hal ini dikarenakan keadaan transisi pertama/TS-1 bersifat lebih polar dan cocok dengan [EMIM][TfO] yang bersifat lebih polar pula. Sedangkan, pada tahap reaksi ke-2 dan ke-3 energi pengaktifan lebih minim pada pelarut [BMIM][BF4], sebesar 195.316 dan 354.290 kJ.mol-1, karena sifat keadaan transisi dan pelarut yang tidak terlalu polar. Ke depannya, perlu dilakukan percobaan di laboratorium untuk mengetahui yield dan variabel lain yang tidak dapat ditemukan dengan metode komputasi

Computation Study of Radioisotopes Gallium-68 (68Ga) Production using Long-lived & High Activity methods

Radioisotopes used for gamma-ray-based diagnostics have the main problem that imaging resolution quality.Gallium-68 is a positron (β+) emitting radioisotope that has better imaging resolution than gamma-based radioisotopes. Gallium-68 (68Ga) can be produced by irradiating natural gallium or zinc-68 enriched as a target with protons in an accelerator facility. Indonesia has planned to build a cyclotron type accelerator that operates in 13 MeV proton energy and 50 µA proton beam who has initials named DECY-13. Before it was commissioned for radioisotopes production purpose that was must conduct a preliminary study to determine 68Ga optimum irradiation time and properties, one of which was the monte carlo computation method using PHITS v3.24 software. Simulations were begun by irradiating proton with natural gallium target for 25 days with 2 days cooling and zinc-68 enriched for 120 minutes with cooling 10 minutes. The results at EOB of the long-lived process using the natGa target obtained total radioactivity of 189.42 MBq (5.12 mCi). The total radioactivity result of high activity process which used 68Zn enriched as a target was 268.6 GBq (7.259 Ci). the radioactivity was compared with another accelerator, that the long-lived process was too small and uneconomical to done, but the high activity process was feasible to produce. The results of this research expected will be considered as a feasibility study for the 68Ga production process in Indonesia in the future

Structural and photocatalytic properties of TiO2/Zeolite synthesized using sol-gel method

Titanium dioxide (TiO2) is supported into natural zeolite to enhance its photocatalytic activity. TiO2/zeolite is synthesized using sol-gel method at composition ratio of 5:95; 10:90; 20:80 and 30:70%. Structural properties are measured by X-ray diffraction showed TiO2/zeolite in various composition has characteristic of anatase and modernite phase. The energy dispersive spectroscopy characterization shows TiO2/zeolite containing Ti element which indicates that TiO2 is successfully supported into natural zeolite. Vibration mode of Infrared and Raman spectra tend shifted to higher wavenumber as increasing of TiO2 content indicating the higher energy vibration due to molecular interaction between TiO2 and zeolite. Photocatalytic activity test toward methylene blue degradation shows that TiO2/zeolite has higher activity than TiO2 and zeolite itself

Preparation and properties of Ti0.997V0.003O2 photocatalyst supported on Indonesian natural zeolite using sonochemical method

Anatase phase of Titanium dioxide (TiO2) is a wide bandgap semiconductor which is active as photocatalyst material under ultraviolet light irradiation. Vanadium dopant has reported to enhance its photocatalytic properties toward visible light irradiation. However, vanadium doped TiO2 has several limitations for further practical application such as its low surface area and difficult in recycling due to its superfine particle. Supporting this material into porous and large surface material like zeolite material supposed to improve its photocatalytic properties. In this research, vanadium doped TiO2 (Ti0.997V0.003O2) photocatalyst was supported on Indonesian natural Zeolite using sonochemical method to study the structural and optical properties of supported photocatalyst. Ti0.997V0.003O2 was loaded into zeolite at various concentration ranging from 10 to 30 % w/w. The X-Ray Diffraction (XRD) data showed that Ti0.997V0.003O2/Zeolite at various concentrations have characteristic of anatase, rutile and mordenite phase structure. Infrared spectra showed the typical vibrational mode of TiO2 and mordenite phase. The sharp peak at 1370 cm-1 which is attributed to the lattice vibration of TiO2 became weaker due to vanadium dopant. The Raman spectra showed that the anatase vibration mode position shifted to higher wavenumber caused by the interaction between Ti0.997V0.003O2 and zeolite. Diffuse Reflectance Spectroscopy (DRS) data revealed that 15% of Ti0.997V0.003O2 on Zeolite has the highest visible light absorption and the lowest band gap energy (2.77 eV or 447 nm) in comparison to the others composition

Sintesis zeolit NaX dari kaolin Blitar dengan alkali fusi menggunakan metode hidrotermal dan sonikasi variasi waktu kristalisasi

INDONESIA: Penggunakan kaolin Blitar sebagai sumber silika dan alumina untuk sintesis zeolit NaX telah dilakukan. Kaolin diubah terlebih dahulu menjadi metakaolin melalui proses alkali fusi. Proses alkali fusi dilakukan dengan rasio berat NaOH/kaolin 2 :1. Sintesis zeolit NaX dilakukan dengan variasi metode hidrotermal dan metode sonikasi serta variasi waktu 2 jam dan 4 jam pada kedua metode. Sitesis zeolit melalui proses hidrotermal menggunakan suhu 100 oC sedangkan sintesis zeolit metode sonikasi menggunakan suhu 70 oC. Karakteristik kaolin, metakaolin dan zeolit NaX hasil sintesis telah diketahui melalui analisis dengan difraksi sinar-X (XRD) untuk mengetahui jenis zeolit, spektroskopi inframerah (FTIR) untuk mengetahui gugus fungsi zeolit yang terbentuk, dan SEM untuk mengetahui morfologi. Kaolin alam Blitar mengandung kaolin serta pengotor kuarsa yang tinggi, setelah diubah menjadi metakaolin terbentuk sodium silikat serta sedikit metakaolin. Zeolit yang dihasilkan dari metode hidrotermal terdiri dari zeolit NaX pada waktu 2 jam dan campuran zeolit NaX serta sodalit pada waktu kristalisasi 4 jam. Zeolit yang dihasilkan dari metode sonikasi berupa zeolit NaX baik pada waktu kristalisasi 2 jam maupun 4 jam. Perubahan kaolin menjadi metakaolin pada spektra FTIR ditandai dengan menghilangnya serapan pada daerah 1037, 912, dan 795 cm-1 pada spektrum metakaolin. Spektra zeolit hasil sintesis memiliki serapan pada daerah 984, 741, dan 560 cm-1 yang merupakan puncak khas zeolit faujasit. Morfologi kaolin berupa lempengan yang berlapis-lapis, sementara metakaolin tidak beraturan/amorf, sedangkan morfologi zeolit hasil sintesis berubah kristal kubus dengan ukuran kristal yang semakin besar dengan meningkatnya waktu kristalisasi. ENGLISH: The use of Blitar Kaolin as a silica and alumina source for synthesis of NaX zeolite has been performed. Kaolin was converted to metakaolin using alkali fusion method. Alkali fusion method was carried out using weight ratio NaOH/kaolin 2:1. NaX zeolite was synthesized using hydrothermal and sonication method with time variation 2 hours and 4 hours of both method. Synthesis through hydrothermal process using temperature 100 oC and sonication method using temperature 70 oC. The characteristics of kaolin, metakaolin and NaX zeolites were known by X-ray Diffraction (XRD) analysis to determine the type of zeolite, Fourier Transform Infrared (FTIR) to determine the functional group of zeolite, and Scanning Electron Microsope (SEM) to determine its morphology. Blitar natural kaolin contain kaolin and high contaminant of quartz, after converted to metakaolin was formed sodium silicate and few metakolin. Zeolite that formed using hydrothermal method was NaX zeolite on 2 hours crystalization and mixture of NaX zeolite and sodalite on 4 hours crystalization. Zeolite that formed using sonication method was NaX zeolite either at 2 hours or 4 hours cristalization time. FTIR spectra indicate changes in the kaolin into metakaolin is characterized by the disappearance of absorption at area 1037, 912, and 795 cm-1 in the spectrum of metakaolin. The synthesized zeolite spectra have absorptions in regions 984, 741, and 560 cm-1 which is typical absorbtion of faujasite zeolite. The morphology of kaolin is a multi-layered plate, while metakaolin is irregular/amorf, the synthesized zeolite morphology is cubic crystal with the size of the larger zeolite crystals increasing with increasing crystallization time

Computation Study of Radioisotopes Gallium-68 (68Ga) Production Using Long-lived & High Activity Methods

Radioisotopes used for gamma-ray-based diagnostics have the main problem that imaging resolution quality.Gallium-68 is a positron (β+) emitting radioisotope that has better imaging resolution than gamma-based radioisotopes. Gallium-68 (68Ga) can be produced by irradiating natural gallium or zinc-68 enriched as a target with protons in an accelerator facility. Indonesia has planned to build a cyclotron type accelerator that operates in 13 MeV proton energy and 50 µA proton beam who has initials named DECY-13. Before it was commissioned for radioisotopes production purpose that was must conduct a preliminary study to determine 68Ga optimum irradiation time and properties, one of which was the monte carlo computation method using PHITS v3.24 software. Simulations were begun by irradiating proton with natural gallium target for 25 days with 2 days cooling and zinc-68 enriched for 120 minutes with cooling 10 minutes. The results at EOB of the long-lived process using the natGa target obtained total radioactivity of 189.42 MBq (5.12 mCi). The total radioactivity result of high activity process which used 68Zn enriched as a target was 268.6 GBq (7.259 Ci). the radioactivity was compared with another accelerator, that the long-lived process was too small and uneconomical to done, but the high activity process was feasible to produce. The results of this research expected will be considered as a feasibility study for the 68Ga production process in Indonesia in the future