Claim Missing Document
Check
Articles

Found 21 Documents
Search

RELATION OF ELECTRONIC STRUCTURES WITH THEIR ANTIMALARIAL ACTIVITIES ON ARTEMISININ DERIVATIVES Ria Armunanto; Sri Sudiono
Indonesian Journal of Chemistry Vol 4, No 3 (2004)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (202.7 KB) | DOI: 10.22146/ijc.21856

Abstract

Relation of electronic structures with their anti malaria activities on artemisinin derivatives was evaluated by means of quantitative structure activity relationship (QSAR) method. To describe electronic structures, atomic charges and dipol moments calculated by quantum mechanics on PM3 semiempirical level. A linear relation between activities and electronic structures was used to construct linear equation models. An equation model showing a good statistically criteria and a realibility of antimalarial activity was chosen to be used to design a compound with new activities against P. facilparum. Results show that 13 equation models were obtained, showing only three models with a good criteria. O2 and C4 atoms were observed for a key role of an improvement of the antimalarial activity.
STUDY OF THERMAL AND ACID STABILITY OF BENTONITE CLAY Karna Wijaya; Ani Setyo Pratiwi; Sri Sudiono; Emi Nurahmi
Indonesian Journal of Chemistry Vol 2, No 1 (2002)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (257.885 KB) | DOI: 10.22146/ijc.21929

Abstract

The thermal and acid stability of the bentonite clays (Na- and Ca-bentonite) have been tested. The thermal stability testing has been carried out by heating 5 gram of the clays  for five hours at 200, 300 and 500 °C respectively, meanwhile acid stability testing was performed by immersing 5 gram clays into 100 mL sulphuric acid 1M, 2M and 3M for 24 hours. The tested clays, then were characterized by means of X-Ray difractometry and IR-spectroscopy methods. The characterization results showed that upon heating, both Ca- and Na-bentonites indicated same thermal stability. However, upon acid treatment, Na-bentonite was found relatively stabiler and more resistance then Ca-bentonite.
The Role of Carboxyl and Hydroxyl Groups of Humic Acid in Removing AuCl4- from Aqueous Solution Sri Sudiono; Mustika Yuniarti; Dwi Siswanta; Eko Sri Kunarti; Triyono Triyono; Sri Juari Santosa
Indonesian Journal of Chemistry Vol 17, No 1 (2017)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (403.241 KB) | DOI: 10.22146/ijc.23620

Abstract

Humic acid (HA) extracted from peat soil according to the recommended procedure of the International Humic Substances Society (IHSS) has been tested to remove AuCl4- from aqueous solution. The removal was optimum at pH 2.0 and it was mainly dictated by attachment through hydrogen bonding to unionized carboxyl (–COOH) groups and reduction by the action of the hydroxyl (–OH) groups to gold (Au) metal. The removal of AuCl4- improved after HA was purified through repeated immersion and shaking in a mixed solution containing 0.1 M HCl and 0.3 M HF. When the purification led to the sharp decrease in ash content from 39.34 to 0.85% (w/w) and significant increase in both the –COOH and –OH contents from 3240 to 3487 mmol/kg and from 4260 to 4620 mmol/kg, respectively; the removal of AuCl4- improved from 0.105 to 0.133 mmol/g. This improvement of AuCl4- removal by the purified HA was accompanied by higher ability in reduction to Au metal. The attached AuCl4- on –COOH groups of both crude and purified HAs was qualitatively observed by the characterization result of FT-IR spectroscopy, while the presence of Au metal on the surface of those HAs was verified by the characterization result of XRD.
Synthesis of Iron-Doped Zirconium Titanate as a Potential Visible-Light Responsive Photocatalyst Rian Kurniawan; Sri Sudiono; Wega Trisunaryanti; Akhmad Syoufian
Indonesian Journal of Chemistry Vol 19, No 2 (2019)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (243.375 KB) | DOI: 10.22146/ijc.38616

Abstract

Synthesis and properties of iron-doped zirconium titanate (ZrTiO4) as a potential visible-light-responsive photocatalyst had been conducted. Various iron dopant concentration and calcination temperature were investigated toward the properties of Fe-doped ZrTiO4. The photocatalyst material was synthesized by sol-gel and impregnation method. Titanium tetraisopropoxide (TTIP) was used as a precursor, embedded on zirconia fine powder. A certain amount of iron (1, 3, 5, 7 and 9 wt.%) was introduced into the photocatalyst system from iron(II) sulfate heptahydrate (FeSO4·7H2O). Photocatalyst with various iron concentration calcined at 500 °C. ZrTiO4 with 5% iron additionally was calcined at 700 and 900 °C. Characterization was performed by using XRD, FT-IR, SR-UV, and SEM-EDX. The presence of iron on the surface of ZrTiO4 was proved by EDX analysis. Fe-doped ZrTiO4 with the lowest bandgap (2.83 eV) is 7% of iron content after calcination at 500 °C.
Synthesis of Activated Carbon/Chitosan/Alginate Beads Powder as an Adsorbent for Methylene Blue and Methyl Violet 2B Dyes Margaretha Aditya Kurnia Purnaningtyas; Sri Sudiono; Dwi Siswanta
Indonesian Journal of Chemistry Vol 20, No 5 (2020)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (370.415 KB) | DOI: 10.22146/ijc.49026

Abstract

The activated carbon-chitosan-alginate (KKA) beads powder was synthesized to form an adsorbent for the cationic dyes, methylene blue (MB) and methyl violet 2B (MV 2B). The aims of this research were to determine the optimum composition of KKA beads powder for the adsorption of cationic dyes and to investigate the effect of pH, adsorbent mass, contact time, and initial concentration of MB and MV 2B dyes. A desorption study was also implemented to predict the adsorption mechanisms of MB and MV 2B dyes. The KKA beads powder was prepared by mixing chitosan, Na-alginate with various variation of masses (0.6; 0.8; 1.0; and 1.2 g) and activated carbon. The KKA beads were immersed in a CaCl2 solution. The KKA beads powder was characterized using FTIR spectroscopy and SEM. The desorption study was conducted in NaCl (0.1 M and 1.0 M), ethanol (40% and 60%), and pH 4 solution. The result showed that the KKA beads powder had been successfully created, with maximum adsorption capacities of 1.34 mmol g–1 for MB and 1.23 mmol g–1 for MV 2B. The kinetics and isotherms of MB and MV dyes adsorption on the KKA beads powder followed pseudo second order kinetics model and Freundlich isotherm. The desorption study showed that 60% ethanol was the most effective desorption solution for cationic dyes.
Study of Mangosteen Peel (Garcinia mangostana L.) Waste Capability to Recover Au(III) and Ag(I) in Aqueous Solution Mellia Harumi; Rian Kurniawan; Agustiwandina Saputri; Dian Hanna Saraswati; Meissha Ayu Ardini; Sri Sudiono
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.57670

Abstract

Electronic waste (e-waste) has been confirmed containing some precious metals such as gold and silver. Mangosteen peel waste as eco-friendly adsorbent has been studied to recover Au(III) and Ag(I) successfully. Recovery was started through adsorbent preparation, consisting of soxhlet extraction and maceration. About 100 mg of adsorbent was dispersed into Au(III) and Ag(I) solutions in various pH conditions (2–6). The result proves that the optimum adsorptions of Au(III) and Ag(I) are at pH 2 and pH 6, respectively. Au(III) adsorption follows the isotherm model of Langmuir with a maximum capacity of 0.580 mmol/g (114.27 mg/g). Ag(I) adsorption follows the isotherm model of Freundlich with a maximum capacity of 0.511 mmol/g (55.10 mg/g).
Codoping Effect of Nitrogen (N) to Iron (Fe) Doped Zirconium Titanate (ZrTiO4) Composite toward Its Visible Light Responsiveness as Photocatalysts Rizka Hayati; Rian Kurniawan; Niko Prasetyo; Sri Sudiono; Akhmad Syoufian
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.70146

Abstract

Iron (Fe) and nitrogen (N) were introduced as dopants into zirconium titanate (ZrTiO4) in order to study the codoping effects of nitrogen on iron-doped zirconium titanate (Fe,N-codoped ZrTiO4) composite. Titanium tetraisopropoxide (TTIP), zirconia (ZrO2), urea, and iron(II) sulfate heptahydrate were used as the source of TiO2, semiconductor supports, source of nitrogen, and iron, respectively. A specific amount of iron (1, 3, 5, 7, and 9 wt.%) and a fixed nitrogen content (10 wt.%) were doped into the ZrTiO4 lattice. Various calcination temperatures (from 500 to 900 °C) were also applied to investigate the crystal structure of the composite. The composites were characterized by X-ray powder diffractometer (XRD), Fourier-transform infrared spectrophotometer (FT-IR), scanning electron microscope with energy dispersive X-Ray spectrometer (SEM-EDX), and specular reflectance UV-Vis (SR-UV). The lowest bandgap energy of 2.62 eV was obtained in the composite with 3 wt.% of Fe and 10 wt.% of N calcined at 500 °C.
Copper-and-Nitrogen-Codoped Zirconium Titanate (Cu-N-ZrTiO4) as a Photocatalyst for Photo-Degradation of Methylene Blue under Visible-Light Irradiation Lenny Rahmawati; Rian Kurniawan; Niko Prasetyo; Sri Sudiono; Akhmad Syoufian
Indonesian Journal of Chemistry Vol 23, No 2 (2023)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.78908

Abstract

Synthesis and characterization of copper-and-nitrogen-codoped zirconium titanate (Cu-N-ZrTiO4) as a photocatalyst for the degradation of methylene blue (MB) have been conducted. The main purpose of this research was to investigate the co-doping effect of copper and nitrogen dopants in ZrTiO4 as a photocatalyst for the photodegradation of MB. Titanium-(IV) tetraisopropoxide (TTIP) was dissolved into ethanol and mixed with aqueous zirconia (ZrO2) suspension containing 10% nitrogen (N) (w/w to Ti) from urea and various amount of copper as dopants. The calcination was performed at temperatures of 500, 700, and 900 °C. The composites were characterized using Fourier transform infrared spectrophotometer (FTIR), X-ray diffractometer (XRD), scanning electron microscopy with energy dispersive X-ray (SEM-EDX) mapping, and specular reflectance UV-Visible spectrophotometer (SRUV-Vis). The degradation of 4 mg L−1 MB solution was conducted for various irradiation times. Characterization shows a significant decrease of the ZrTiO4 band gap from 3.09 to 2.65 eV, which was given by the composite with the addition of 4% Cu and calcination of 900 °C. Cu-N-ZrTiO4 composite can degrade MB solution up to 83% after 120 min under the irradiation of visible light.
The Influence of Metal Loading Amount on Ni/Mesoporous Silica Extracted from Lapindo Mud Templated by CTAB for Conversion of Waste Cooking Oil into Biofuel Cahyarani Paramesti; Wega Trisunaryanti; Savitri Larasati; Nugroho Raka Santoso; Sri Sudiono; Triyono Triyono; Dyah Ayu Fatmawati
Bulletin of Chemical Reaction Engineering & Catalysis 2021: BCREC Volume 16 Issue 1 Year 2021 (March 2021)
Publisher : Masyarakat Katalis Indonesia - Indonesian Catalyst Society (MKICS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.9767/bcrec.16.1.9442.22-30

Abstract

The synthesis and characterization of Ni/mesoporous silica (Ni/MS) catalysts from Lapindo mud with various metal loading for the hydrocracking of waste cooking oil into biofuel has been conducted. The MS was synthesized by the hydrothermal method using CTAB as a template. The nickel-metal of 4, 6, and 8 wt% was loaded into the MS using salt precursors of Ni(NO3)2.6H2O via wet impregnation, produced the Ni(4)/MS, Ni(6)/MS, and Ni(8)/MS catalysts, respectively. The materials produced were then characterized by X-ray Powder Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FT-IR), and Surface Area Analyzer (SAA), and Absorption Atomic Spectrophotometry (AAS). The catalytic activity test was carried out for hydrocracking of waste cooking oil and the resulted liquid product was analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). The results showed that the specific surface area of Ni(4)/MS, Ni(6)/MS, and Ni(8)/MS catalysts are 63.08, 91.45, and 120.45 m2/g, respectively. The liquid products of the hydrocracking using Ni(4)/MS, Ni(6)/MS, and Ni(8)/MS catalysts were 80.57, 74.63, and 75.77 wt%, where the total biofuel produced was 55.46, 50.93, and 54.05 wt%, respectively. Based on these results, Ni(4)/MS material was successfully used as the most potent catalyst in the hydrocracking of waste cooking oil into the biofuel. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 
Photodegradation of Phenol under Visible Light Irradiation Using Cu-N-codoped ZrTiO4 Composite as a High-Performance Photocatalyst Wanda Putra Fauzi; Rian Kurniawan; Sri Sudiono; Niko Prasetyo; Akhmad Syoufian
Indonesian Journal of Chemistry Vol 24, No 2 (2024)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijc.90365

Abstract

Codoping of nitrogen and copper into zirconium titanate composite (Cu-N-codoped ZrTiO4) was carried out through a sol-gel process. This study aimed to investigate the effect of copper and nitrogen dopants on the photocatalytic activity of ZrTiO4 composite in degrading phenol. To prepare the composite, an aqueous suspension of zirconia (ZrO2) alongside a fixed amount of urea and various amount of copper sulfate was added dropwise into diluted titanium(IV) tetraisopropoxide (TTIP) in ethanol. The composites were calcined at temperatures of 500, 700, and 900 °C. Fourier-transform infrared spectrophotometry (FTIR), X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray (SEM-EDX) mapping, and specular reflectance UV-visible spectrophotometry (SR UV-vis) were used for their characterization of composite. The photocatalytic activity was evaluated by adding the composite into a 10 mg L−1 phenol solution for various irradiation time spans. The remaining concentration of phenol solution was determined by absorption at 269 nm. Cu-N-codoped ZrTiO4 composite containing 5% Cu calcined at 500 °C demonstrated the highest observed rate constant and a significant band gap decrease from 3.13 to 2.68 eV.