Wega Trisunaryanti
Chemistry Department, Faculty of Mathematics and Natural Sciences Gadjah Mada University, Yogyakarta

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PREPARATION, CHARACTERIZATIONS AND MODIFICATION OF Ni-Pd/NATURAL ZEOLITE CATALYSTS Wega Trisunaryanti; Endang Triwahyuni; Sri Sudiono
Indonesian Journal of Chemistry Vol 5, No 1 (2005)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (175.92 KB) | DOI: 10.22146/ijc.21838

Abstract

Preparation, and modification of Ni-Pd/natural zeolite as well as their characterizations had been carried out. The aim of this research for the fututure is to prepare the best characters catalyst for the conversion of waste plastics fraction to gasoline fraction (C5-C12 hydrocarbons). The preparation of catalysts was performed by reacting a natural zeolite with the precursor of Ni(NO3)2. 9H2O and PdCl2 in an ammonia solution (25%). The modifications were performed by varying the rasio of Ni/Pd loaded to the zeolite, whereas the Pd was previously loaded and total metal content was 1 wt.% based on the zeolite. The characterization of catalysts included determination of acidity gravimetrically by adsorption of ammonia or pyridine vapour  base method, metal content by Atomic Adsorption Spectrophotometer (AAS) and X-ray Fluoresence (XRF) and crystallinity by X-ray Diffraction (XRD). The treatment of catalysts using Etilene Diamine Tetra Acetic acid  (EDTA) was performed to study the metal distribution on the outer or inner surface of the zeolite. The characterization results showed that the loading of metals to the zeolite increased its acidity and decreased its spesific surface area, however, did not defect its crystallnity.  The metals loaded on the zeolite were distributed inside the pore and at outer surface of the zeolite. For all catalyst samples, the acidities determined using ammonia were higher than those of pyridine, and the acidities determined before the EDTA treatment was lower than those after the treatment.  Metal contents of the zeolite before the EDTA treatment were higher than those after the treatment. The EDTA treatment enhanced the crystallinity of the sampel. The relationship between the metal rasio towards the acidity of the catalyst samples were in variation. Catalyst samples produced in this research have good characters, thus promisingly can be used for conversion process of waste plastics to gasoline fraction.
STUDY OF MATRIX EFFECT ON THE ANALYSIS OF Ni AND Pd BY AAS IN THE DESTRUATS OF HIDROCRACKING CATALYSTS USING AQUA REGIA AND H2SO4 Wega Trisunaryanti; Mudasir Mudasir; Siti Saroh
Indonesian Journal of Chemistry Vol 2, No 3 (2002)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (77.51 KB) | DOI: 10.22146/ijc.21914

Abstract

 The matrix effect of various metals on the analysis of nickel and palladium in destruate of catalysts of Butonian asphalt-derived asphaltene by atomic absorption spectroscopy have been investigated. Samples were dissolved by wet decomposition method using aqua regia and then followed by concentrated H2SO4. The solution was evaporated to dryness on a sand-bath. Study of matrix effect was carried out by comparing the absorbance of Ni and Pd with and without the adding of various concentration of metals in the samples. The calibration curve and standard addition methods were applied in the analysis of Ni and Pd. Result of the study showed that matrix effect toward absorbance of Ni is mostly caused by Al and Si contents in the concentration range of 200-500 ppm. Al content in the concentration of 500 ppm, and Si content in the concentration range of 100-500 ppm cause the matrix effect in the analysis of Pd. However, the change in absorbance of Ni and Pd is still below tolerable limit of 10%. The content of Ni in Pd-Ni / zeolit-Y, Ni-Pd/ zeolit-Y, Mo-Ni/ g-alumina, and Ni-Mo / g-alumina with calibration curve technique were 7.44 ± 0.021; 7.62 ± 0.052; 7.75 ± 0.054; and 2.69 ± 0.062 respectively and with standard addition technique were 6.82 ± 0.066; 7.23 ± 0.112; 7.39 ± 0.099; and 2.35 ± 0.055 respectively. Pd content in Pd-Ni / zeolit-Y and Ni-Pd/ zeolit-Y with calibration curve technique were 2.74 ± 0.044 and 2.49 ± 0.051 and with standard addition technique were 2.90 ± 0.015 and 2.69 ± 0.042.