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1.
ACS Omega ; 9(13): 15232-15238, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38585132

RESUMEN

Calcined biowaste durian peel (BDP) contains 86% potassium element as the main compound and has successfully catalyzed the transesterification of palm oil to biodiesel at room temperature. The effect of catalyst weight, molar ratio of palm oil to methanol, reaction time, and rotational speed of the homogenizer device was investigated on biodiesel conversion and yield. The highest biodiesel conversion of 97.4 ± 0.3% was achieved using the following reaction conditions: a catalyst weight of 5 wt %, a molar ratio of palm oil to methanol of 1:15, a reaction time of 10 min, and a rotational speed of 6000 rpm. Unfortunately, calcined BDP could not hold its catalytic activity in the reusability study. The biodiesel conversion was decreased in the second cycle due to the decrease of both catalyst weight and concentration of potassium ions after the first cycle. However, the calcined BDP paired with a homogenizer device could produce biodiesel in a short reaction time and at room temperature.

2.
RSC Adv ; 13(9): 6217-6224, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36825289

RESUMEN

Banana peels as agro-waste residues contain potassium oxide as the main component after calcination. The calcined waste banana peels (WBPs) successfully transesterified palm oil to biodiesel at room temperature using a homogenizer. The catalyst was characterized by TGA, SEM, XRD and XRF. The catalytic activity of calcined WBPs was determined using parameters of the molar ratio of palm oil to methanol, catalyst weight, reaction time and rotational speed of the homogenizer. The highest biodiesel conversion of 97.7 ± 0.6% was achieved with a molar ratio of 1 : 15, catalyst weight of 7 wt%, reaction time of 30 min and rotational speed of 6000 rpm. Unfortunately, the calcined WBP cannot be reused unless some fresh catalyst is added to defend its catalytic activity, as the concentration of K2O decreases after the reaction. However, the catalyst showed better performance as the transesterification reaction could be carried out at room temperature in a short reaction time using a homogenizer compared with other methods.

3.
ACS Omega ; 8(19): 17234-17244, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37214712

RESUMEN

In this study, CuO-TiO2 nanofiber catalysts were fabricated by an electrospinning process, followed by thermal annealing at various temperatures ranging from 300 to 700 °C. The phase transformation from CuO to metallic Cu was carried out through immersion treatment in NaBH4 solution. The resulting CuO-TiO2 and Cu-CuO-TiO2 nanofibrous mats were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) analysis. The results revealed that the crystalline phase composition of the nanofibrous mats considerably affected the efficiency of photocatalytic reduction, where the CuO-TiO2 catalysts with a predominant anatase content was found to be more photoactive than the rutile phase. Similarly, the presence of both Cu and CuO species was more beneficial for promoting the activity of fibers by acting as an interim location for facilitating the electron transfer. The fabricated Cu-CuO-TiO2 nanofibrous mat with a ratio presented high conversion (∼99%) within several minutes with the apparent pseudo-first-order rate constant of 0.42 and 0.50 min-1 in the absence and presence of UV light irradiation as well as excellent stability in recycling runs with a stable conversion efficiency of 97% or higher over five successive catalytic cycles.

4.
Heliyon ; 9(6): e16402, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37292359

RESUMEN

Insect larvae contain sufficient oil comparable with oleaginous biomass, and hence have potency as alternative biodiesel resources. The direct transesterification of Black Soldier Fly (BSF) larvae have conducted using a controllable crushing device (CCD) and a homogeneous base as a catalyst. The effect of catalyst concentration (wt.%), ratio BSF larvae to methanol (wt./v), reaction time (min) and rotational speed (rpm) on biodiesel conversion was determined. The maximum conversion of 93.8% was achieved at room temperature after 20 min of reaction time and ratio larvae to methanol of 1:2 (wt./v), catalyst concentration of 7 wt% and rotational speed of 3000 rpm. In addition, the green metrics calculation showed that this method produces less waste and uses less solvent. Some of the BSF-biodiesel properties meet the biodiesel standard. The CCD-intensified the DT of BSF larvae is a promising alternative for green and energy-saved biodiesel production.

5.
J Adv Pharm Technol Res ; 11(1): 1-5, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32154151

RESUMEN

This study aims to provide information on physicochemical properties of Arenga pinnata endosperm (APE) and its antidiabetic activity for utilization in the food and pharmaceutical industries. The antidiabetic effect of APE was studied through an observational experiment on the blood glucose level of rats. The physicochemical properties of APE were determined using a texturometer, X-ray powder diffraction, Brookfield viscometer, scanning electron microscopy, Fourier-transform infrared spectroscopy, and light microscope. The APE was categorized based on its texture into three groups. The crystal structure of APE is microspore and amorf while the hydrogel has a non-Newtonian property and is stable at 50°C. The viscosity index was increased in the increasing temperature with the order of high viscosity of APE being 1, 2, and 3. The hydrogel shape of APE 1 and 3 was lameral in the concentration of 1.25%. For antidiabetic study, the findings demonstrated that the APE could reduce the blood glucose level. The APE powders 1 and 2 with the respective weight of 50 and 200 mg have significant effects on reducing rat blood glucose level compared to the diabetic rats. Based on these properties, APE could potentially be used as a natural antidiabetic food without having any side effect and in the pharmaceutical industry for some purposes.

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