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1.
RSC Adv ; 13(46): 32648-32659, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37936636

RESUMO

Saponin is a plant-derived chemical with an amphiphilic glycoconjugate structure extracted from sapindaceae plants like Sapindus rarak. This study investigated saponin extract of Sapindus rarak as a natural template for formation of mesoporous zeolite Y. Surface area and mesoporosity of zeolite Y were improved with optimization of Sapindus rarak extract (SRE) concentration (Y-Ln; n = 2, 5, 10 or 15 mL), reaching 216.26 m2 mesoporous area and 0.214 cm3 g-1 mesoporous volume for Y-L10 samples. A different loading of Ni was impregnated onto Y-L10 zeolite to improve Lewis/Brønsted acidity as catalysts in the deoxygenation of Reutealis trisperma oil (RTO) into hydrocarbon fuels. Impregnating 15% Ni on NaY zeolite enhanced Lewis acidity to 0.4556 mmol g-1, producing 48.8% liquid oil with 85.43% degree of deoxygenation. A high selectivity towards C15 and C17 hydrocarbon was analyzed from liquid yield, indicating the contributing factor from Lewis acidity and mesoporosity to enhance deoxygenation and prevent the hydrocracking reaction.

2.
RSC Adv ; 13(45): 31989-31999, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37915446

RESUMO

Conversion of red mud (RM) that contains a high level of silica, alumina and iron minerals into heterogenous catalysts, offers a route for the utilization of abundant toxic by-products of bauxite refining. In this study, the conversion of red mud into mesoporous Fe-aluminosilicate produced selective catalysts for the deoxygenation of waste cooking oil to green diesel hydrocarbons. Direct conversion of red mud in the presence cetyltrimethylammonium bromide into Fe-aluminosilicate (RM-CTA) produced a highly mesoporous structure with oligomeric Fe2O3 clusters within the pores. When red mud was treated with citric acid (RM-CA-CTA), a wide distribution of Fe2O3 particles was obtained on the aluminosilicate external surface. TEM analysis showed a well-defined hexagonal mesoporosity of Fe-aluminosilicate obtained from untreated red mud, while the treated red mud produced lower regularity mesopores. RM-CTA exhibits 60% WCO conversion and 83.72% selectivity towards liquid products with 80.44% diesel hydrocarbon (C11-C18) yield. The high selectivity was due to the high acidity of Fe-aluminosilicate to dissociate the C-O bond and the regularity of mesostructure for efficient hydrocarbon diffusion, preventing a cracking reaction.

3.
Heliyon ; 8(12): e11997, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36536907

RESUMO

The application of silica gel adsorbent synthesized from chemical bottle waste to remove zinc ions in the solution has been carried out. The synthesis of silica gel was carried out using alkaline fusion followed by sol-gel reactions. The chemical glass bottle container was made from borosilicate glass which was different from glass bottles for food and beverage that has been studied in previous studies. The Zn2+ adsorption was optimized using Box-Behnken Design (BBD). Box-Behnken Design was applied to study the optimum zinc ion removal and the input variables interaction. The input variables optimized were adsorbent dosage (1.0 - 2.0 g), initial zinc ion concentration in the solution (25 - 100 ppm), contact time (15 - 45 min), and pH (4 - 9). Response Surface Methodology (RSM) was applied to visualize the input variables' correlation to zinc ion removal. The optimum zinc ion removal was achieved at an adsorbent dosage of 2 g, initial concentration of 35 ppm, contact time of 45 min, and pH 8, which was 99.56%. The optimization of adsorption isotherm obtained that the adsorption follows the Langmuir isotherm model. The silica gel obtained was characterized using SEM-EDX and BET to obtain silica gel properties. The SEM-EDX showed a spherical shape of silica gel. Silica gel containing zinc (Zn) was observed from SEM-EDX after the adsorption process. A pore diameter of 42.098 nm and surface area of 297.083 m2/g were obtained from BET analysis of synthesized silica gel.

4.
Polymers (Basel) ; 14(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36432918

RESUMO

Solid polymer electrolytes (SPEs) have been successfully fabricated from CS/PEO/NaClO4/Fly ash composite. Chitosan (CS), an organic polymer, was blended with polyethylene oxide (PEO) to enhance its electrochemical properties. However, SPEs based on CS/PEO composites have low conductivity. Fly ash (FA) has been studied to be used as a filler to increase the ionic conductivity of SPEs. In this study, polymer composites based on CS and PEO were developed with the addition of FA as a filler using the solution casting method. The interactions between CS, PEO, NaClO4, and fly ash were observed using FTIR. The SPE characterization using XRD and DSC showed a decrease in crystallinity after the addition of NaClO4 and FA. The SPE composite morphology and elemental distribution were investigated using SEM. SPE conductivity analysis using EIS showed the optimum results for SPE fabricated with a ratio of CS:PEO:NaClO4 = 3:2:7.5, which was 1.02 × 10-4 S cm-1 at 30 °C and increased to 2.13 × 10-3 S cm-1 at 60 °C. The addition of FA (5 wt.%) increased the conductivity to 3.20 × 10-4 S cm-1 at 30 °C and increased to 4.34 × 10-3 S cm-1 at 60 °C.

5.
Materials (Basel) ; 15(8)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35454437

RESUMO

Mesoporous sodalite nanoparticles were directly synthesized from Indonesian kaolin with the addition of CTABr as a mesopore template. The studies highlighted the importance of aging time (3-12 h) and temperature (50-80 °C) on increasing surface area and mesoporosity of sodalite. Indonesian kaolin was used without pre-treatment and transformed to sodalite following the initial molar composition of 10 Na2O: 2 SiO2: Al2O3: 128 H2O. Characterization data revealed the formation of high surface area sodalite with mesoporosity at increasing aging temperatures and times. The presence of CTABr as templates produced sodalites nanoparticles with smaller aggregates than the non-template sodalite. The sodalite sample obtained at 80 °C of crystallization temperature for 9 h (S80H9) displayed the highest mesopore volume (0.07612 cm3/g) and the highest adsorption capacity of Pb2+ (212.24 mg/g). Pb2+ was suggested to adsorb via ion exchange with the Na+ counter cation and physical adsorption.

6.
Polymers (Basel) ; 13(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34883743

RESUMO

The synthesize of solid polymer electrolyte (SPE) based on polyethylene oxide (PEO), NaClO4 and nano-SiO2 was carried out by solution cast technique. Nano-SiO2 was synthesized from sugarcane bagasse using sol-gel method. FTIR analysis was carried out to investigate the bonding between nano-SiO2 and PEO/NaClO4. The morphology of the SPE was characterized using SEM. XRD and DSC analysis showed that SPE crystallinity decreased as nano-SiO2 concentration was increased. Mechanical analyses were conducted to characterize the SPE tensile strength and elongation at break. EIS analysis was conducted to measure SPE ionic conductivity. The PEO/NaClO4 SPE with the addition of 5% nano-SiO2 from sugarcane bagasse at 60 °C produced SPE with the highest ionic conductivity, 1.18 × 10-6 S/cm. It was concluded that the addition of nano-SiO2 increased ionic conductivity and interface stability at the solid polymer electrolyte-PEO/NaClO4.

7.
RSC Adv ; 11(36): 21885-21896, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35480811

RESUMO

The activity of mesoporous Al-MCM-41 for deoxygenation of Reutealis trisperma oil (RTO) was enhanced via modification with NiO nanoparticles. Deoxygenation at atmospheric pressure and under H2 free conditions required acid catalysts to ensure the removal of the oxygenated fragments in triglycerides to form liquid hydrocarbons. NiO at different weight loadings was impregnated onto Al-MCM-41 and the changes of Lewis/Brønsted acidity and mesoporosity of the catalysts were investigated. The activity of Al-MCM-41 was enhanced when impregnated with NiO due to the increase of Lewis acidity originating from NiO nanoparticles and the mesoporosity of Al-MCM-41. Increasing the NiO loading enhanced the Lewis acidity but not Brønsted acidity, leading to a higher conversion towards liquid hydrocarbon yield. Impregnation with 10% of NiO on Al-MCM-41 increased the conversion of RTO to hydrocarbons via the deoxygenation pathway and reduced the products from cracking reaction, consequently enhancing the green diesel (C11-C18) hydrocarbon products.

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