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Stabilitas Zirconium-Silika Molecular Sieve dalam Larutan Basa Mustafa, Anwar; Saputra, Hens
Majalah Ilmiah Pengkajian Industri Vol 7, No 1 (2013): MAJALAH ILMIAH PENGKAJIAN INDUSTRI
Publisher : BPPT

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (857.683 KB) | DOI: 10.29122/mipi.v7i1.3641

Abstract

Telah dilakukan penelitian pengaruh zirconium dalam perbaikan stabilitas silika molecular sieve dalam larutan basa. Struktur molecular sieve yang dibuat adalah hexagonal MCM-41 yang memiliki luas permukaan 1200 m2/g. Pembuatan bahan silika MCM-41 dilakukan menggunakan campuran larutan cethyltrimetilammonium bromida (CTAB), tetraethylorthosilikat (TEOS), natrium hidroksida (NaOH) dan aquades (H2O) dengan perbandingan molar 0,05 : 1,0 : 0,5 : 100. Adapun penambahan zirconium isopropoksida (ZrPr) sejumlah 3% berat terhadap tetraethylorhosilikat. Penambahan zirconium pada MCM-41 tidak merubah karakteristik distribusi ukuran pori, diameter pori rata-rata sekitar 2 nm dengan luas permukaan mencapai 1200 m2/g. Dengan penambahan 3% berat ZrPr dapat meningkatkan stabilitas silika molecular sieve pada larutan basa. Pengamatan struktur dilakukan dengan X-ray diffraction. Karakteristik pori dianalisis dengan metode physisorption menggunakan nitrogen pada 44 K.Kata Kunci : Zircorium, Molecular Sieve, diameter poriAbstractHas conducted research on the effect of zirconium silica molecular sieve improved stability in alkaline solution . Molecular sieve structure is made of hexagonal MCM - 41 which has a surface area of 1200 m2 / g . Preparation of MCM - 41 silica materials was conducted using a mixed solution of cethyltrimetilammonium bromide ( CTAB ) , tetraethylorthosilikat ( TEOS ) , sodium hydroxide ( NaOH ) and distilled water ( H2O ) with a molar ratio of 0.05 : 1.0 : 0.5 : 100 . As for the addition of zirconium isopropoxide ( ZrPr ) a 3 % by weight of the tetraethylorhosilikat . The addition of zirconium in the MCM - 41 does not alter the characteristics of the pore size distribution , average pore diameter of about 2 nm with a surface area to 1200 m2 / g . With the addition of 3 wt% silica ZrPr can increase the stability of molecular sieve in an alkaline solution . Observation of the structure is done with X - ray diffraction . Pore characteristics were analyzed by the method using nitrogen physisorption at 44 K.Keywords : Zircorium , Molecular Sieve , Pore diameter
Stabilitas Zirconium-Silika Molecular Sieve dalam Larutan Basa Mustafa, Anwar; Saputra, Hens
Majalah Ilmiah Pengkajian Industri Vol. 7 No. 1 (2013): Majalah Ilmiah Pengkajian Industri
Publisher : Deputi TIRBR-BPPT

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (857.683 KB) | DOI: 10.29122/mipi.v7i1.3641

Abstract

Telah dilakukan penelitian pengaruh zirconium dalam perbaikan stabilitas silika molecular sieve dalam larutan basa. Struktur molecular sieve yang dibuat adalah hexagonal MCM-41 yang memiliki luas permukaan 1200 m2/g. Pembuatan bahan silika MCM-41 dilakukan menggunakan campuran larutan cethyltrimetilammonium bromida (CTAB), tetraethylorthosilikat (TEOS), natrium hidroksida (NaOH) dan aquades (H2O) dengan perbandingan molar 0,05 : 1,0 : 0,5 : 100. Adapun penambahan zirconium isopropoksida (ZrPr) sejumlah 3% berat terhadap tetraethylorhosilikat. Penambahan zirconium pada MCM-41 tidak merubah karakteristik distribusi ukuran pori, diameter pori rata-rata sekitar 2 nm dengan luas permukaan mencapai 1200 m2/g. Dengan penambahan 3% berat ZrPr dapat meningkatkan stabilitas silika molecular sieve pada larutan basa. Pengamatan struktur dilakukan dengan X-ray diffraction. Karakteristik pori dianalisis dengan metode physisorption menggunakan nitrogen pada 44 K.Kata Kunci : Zircorium, Molecular Sieve, diameter poriAbstractHas conducted research on the effect of zirconium silica molecular sieve improved stability in alkaline solution . Molecular sieve structure is made of hexagonal MCM - 41 which has a surface area of 1200 m2 / g . Preparation of MCM - 41 silica materials was conducted using a mixed solution of cethyltrimetilammonium bromide ( CTAB ) , tetraethylorthosilikat ( TEOS ) , sodium hydroxide ( NaOH ) and distilled water ( H2O ) with a molar ratio of 0.05 : 1.0 : 0.5 : 100 . As for the addition of zirconium isopropoxide ( ZrPr ) a 3 % by weight of the tetraethylorhosilikat . The addition of zirconium in the MCM - 41 does not alter the characteristics of the pore size distribution , average pore diameter of about 2 nm with a surface area to 1200 m2 / g . With the addition of 3 wt% silica ZrPr can increase the stability of molecular sieve in an alkaline solution . Observation of the structure is done with X - ray diffraction . Pore characteristics were analyzed by the method using nitrogen physisorption at 44 K.Keywords : Zircorium , Molecular Sieve , Pore diameter
Release Pattern of Nitrogen and Potassium from Controlled Release Fertilizer (CRF) in the Soil Suwardi, Suwardi; Suryaningtyas, Dyah Tjahyandari; Saputra, Hens; Rosjidi, Mochamad; Mustafa, Anwar; Ghofar, Abdul
JOURNAL OF TROPICAL SOILS Vol. 28 No. 3: September 2023
Publisher : UNIVERSITY OF LAMPUNG

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5400/jts.2023.v28i3.99-106

Abstract

Nitrogen (N) and potassium (K) are macronutrients that plants need for better growth and yield. However, they are readily lost from the soil through volatilization, denitrification, and leaching, aside from being absorbed by plant roots. Thus, a Controlled Release Fertilizer (CRF) may be formulated and applied to maximize the beneficial effects of N and K fertilization. This study aimed to describe the release pattern of ammonium nitrogen (NH4 -N), nitrate nitrogen (NO3 -N), and K from CRF through the laboratory incubation method. Two types of CRF - CRF A (16-16-16) and CRF B (30-6-8), with a non-CRF (Mutiara NPK16-16-16) as Control – were used. Each fertilizer was tested at 600 and 1200 kg ha-1 doses. The results showed that the NH4 -N release was very high at 40 – 60% but declined to almost 0% after 14 weeks. The NO3 -N release rate was 17 – 40% during the first week, followed by a steady increase to nearly 100% by the 14th incubation week. Potassium release ranged from 20% to 30% in the first week, then rose to 30 – 70% at Week 14. Overall, CRF (30-6-8) at a dose of 1200 kg ha-1 showed the slowest rate of nitrogen release.