Sulfuric Acid
Mostrando 1-12 de 209 artigos, teses e dissertações.
-
1. An Eco-Friendly Proposal by Integrating Chromatographic Fingerprinting and Multivariate Control Chart in a Non-Target Analysis to Evaluate Grape Juices from Different Farming Practices
A potential eco-friendly method without organic solvents is presented by integrating a chromatographic fingerprint and multivariate control chart based on Q residuals to differentiate grape juices from different farming practices. The sample preparation was only water dilution, and the mobile phase was water acidified with sulfuric acid, which can be readily
Journal of the Brazilian Chemical Society. Publicado em: 2022
-
2. An alternative route to extract nickel and cobalt from non-commercial laterite ore
Abstract Laterite ores, which represent around two-thirds of nickel reserves, became an important source of nickel and cobalt metals. The objective of the present study was to investigate the efficiency of a hybrid route to extract nickel and cobalt present in a laterite ore sample which was not commercially attractive to be processed through the current rou
REM - International Engineering Journal. Publicado em: 2022
-
3. Preparation of SAPO-34-Based Catalyst for Conversion of Fructose to 5-Hydroxymethylfurfural
Solid acid-catalyzed dehydration of fructose to produce 5-hydroxymethylfurfural (5-HMF) has been a hotspot in biomass conversion research in recent years. In this study, a novel SAPO-34-based catalyst was prepared by consecutive steps of titanium doping, sulfuric acid impregnation, and sulfonic acid functionalization. Characterization of the catalyst with X-
J. Braz. Chem. Soc.. Publicado em: 2021-08
-
4. Acid matrix production from treated natural vermiculite-hydrobiotite
Abstract Given the potential of acid-activated clays in adsorptive and catalytic processes, several studies focusing on acid matrices have grown over the years, making it possible to study vermiculite, a mineral composed of a type 2:1 unit cell with tetrahedral and octahedral sheets. Therefore, this work aimed to study vermiculite treated with acids for the
Cerâmica. Publicado em: 2021-06
-
5. Purification of raw palygorskite: a comparative study involving different processes and dispersing agents
Abstract Palygorskite (Pal) is a natural clay mineral with fibrous morphology and high surface area. Depending on the geological origin, it presents impurities, such as quartz and carbonates, which can harm some of its properties. Therefore, this work seeks to define a viable methodology for the purification of a Brazilian Pal. Two types of mixing processes
Cerâmica. Publicado em: 2021-06
-
6. MODIFICAÇÃO QUÍMICA DO POLIPROPILENO ATRAVÉS DA INTRODUÇÃO DE GRUPOS SULFÔNICOS PARA APLICAÇÃO COMO CATALISADOR EM REAÇÕES DE ESTERIFICAÇÃO
In this work, the chemical modification of pristine polypropylene was carried out through sulfonation reactions with concentrated sulfuric acid (PPS1) and fuming sulfuric acid (PPS2), for production of heterogeneous catalysts used in esterification reactions. Fourier transform infrared spectroscopy, elemental analysis, degree of substitution and ion exchange
Quím. Nova. Publicado em: 2021-04
-
7. Hymenaea parvifolia Huber: dormancy breaking, morphology of fruit, seed and seedling
ABSTRACT The successful use of native species in conservation actions depends on basic knowledge of their biology, beginning with the identification of regenerating individuals in the field, up to the behavior and development of the species from the early stages of germination. Moreover, seed propagation and germination may be limited by the occurrence of do
Rev. Ceres. Publicado em: 2021-04
-
8. Improving seed germination and seedling growth of guava under heat and osmotic stresses by chemical and hormonal seed treatments
ABSTRACT This study, consisting of two independent experiments, was conducted to optimize presowing guava seed treatments and evaluate the optimized treatments in improving germination and seedling growth of guava under heat and osmotic stresses. In the first experiment, seeds of guava cultivar White Flesh Local I were soaked in water, gibberellic acid (GA3)
Bragantia. Publicado em: 2020-12
-
9. Germination responses of Lycium humile, an extreme halophytic Solanaceae: understanding its distribution in saline mudflats of the southern Puna
ABSTRACT Although knowledge about halophytic Solanaceae is scarce, it is known that several species within genus Lycium tolerate salinity. Lycium humile grows in highly saline soils in mudflats near saline Andean lakes. This study evaluated the germination responses of L. humile under different scarification methods, photoperiods, temperatures and saline con
Acta Bot. Bras.. Publicado em: 2020-09
-
10. Potassium recovery from Brazilian glauconitic siltstone by hydrothermal treatments
Abstract Silicate rock Verdete, collected in the central region of Minas Gerais state (Brazil) and composed mostly of micas (glauconite and muscovite) and tectosilicates (K-feldspar and quartz), was hydrothermally treated with several reactants in order to release and recover potassium. The hydrothermal products were characterized by flame photometry, XRD, X
REM, Int. Eng. J.. Publicado em: 2020-06
-
11. Minieditorial: Risco de FA após Ablação de Flutter Dependente de Istmo Cavo-Tricuspídeo: Vale a Pena Fazer a Ablação da FA Simultaneamente?
Considering the size of the Amazon region and the need for studies to establish soil trace metal concentrations in natural environments, the objective of this work was to evaluate heavy metal contents in a toposequence of an Amazon State microbasin. Soil samples were collected in three native forest topographic positions. Samples were opened for analysis by
Arq. Bras. Cardiol.. Publicado em: 2020-05
-
12. VALORES DE REFERÊNCIA DA CONCENTRAÇÃO DE METAIS PESADOS EM SOLOS NA AMAZÔNIA CENTRAL
Considering the size of the Amazon region and the need for studies to establish soil trace metal concentrations in natural environments, the objective of this work was to evaluate heavy metal contents in a toposequence of an Amazon State microbasin. Soil samples were collected in three native forest topographic positions. Samples were opened for analysis by
Quím. Nova. Publicado em: 2020-05