Fabricio Augusto Hansel

Molecular and morphological characterization of hydrochar produced by microwave-assisted hydrothermal carbonization of cellulose

The objective of this work was to characterize the morphology and molecular composition of the hydrochar produced by microwave-assisted hydrothermal carbonization of cellulose. The produced hydrochar consists mainly of aggregate microspheres with about 2.0 µm in diameter, with aliphatic and aromatic structures and the presence of carbonyl functional groups. The aromatic groups are formed mainly by benzofuran-like structures, being chemically different from common cellulose char. Microwave-assisted hydrothermal carbonization yields a functionalized carbon-rich material similar to that produced by the conventional hydrothermal process.

Characterization of Pinus spp needles and evaluation of their potential use for energy.

The demand for new energy sources is growing and awakening interest in the use of forest residues. Charcoal was prepared at carbonization temperatures of 500 oC, 600 °C and 700 °C in order to evaluate the potential use of Pinus sp needles for energy. The anatomical and chemical characteristics of the needles and the charcoal produced were also evaluated. The needles were found to have ash content of 2.32% and gross calorific value of 20.30 MJ/kg. The calorific value increased by 45%, reaching 29.64 MJ/kg, after carbonization carried out at 600 oC. This value is higher than that for charcoal made from eucalyptus (19.25 MJ/kg) and even coconut husks (23.55 MJ/kg), showing the high energy potential of these needles.

Chemical Composition of Essential Oils from Ripe and Unripe Fruits of Piper amalago L. var. medium (Jacq.) Yunck and Piper hispidum Sw.

Abstract The chemical composition of essential oils from unripe and ripe fruits of Piper amalago L. var. medium (Jacq.) Yunck and Piper hispidum Sw. was examined using GC/MS analysis. The analysis of oils from P. amalago revealed a predominance of oxygenated sesquiterpenes and 65 compounds were identified; their main constituents are: (E)- nerolidol (14.2% and 19.9%), germacrene-D-4-ol (10.3% and 12.7%), α-cadinol (11.1% and 8.2%) in 99.6% and 98.7% of the compounds for unripe and ripe fruits, respectively. Piper hispidum revealed a predominance of sesquiterpene hydrocarbons, from which we identified 53 compounds including: α-copaene (28.7% and 36.2%), α-pinene (13.9% and 7.1%), α-pinene (13.3% and 7.5%), and (E)-nerolidol (2.9% and 7.0%) which represented 97.8% and 98.1% of the compound constituents for unripe and ripe fruits, respectively. The essential oils of fruits of P. amalago and P. hispidum are reported for the first time.

Determination of volatile organic compounds in eucalyptus fast pyrolysis bio-oil by full evaporation headspace gas chromatography

This paper reports a full evaporation (FE) headspace gas chromatographic (HS-GC) method for the determination of the volatile organic compounds (VOCs) in bio-oil (i.e. methanol, ethanol, acetone, acetic acid and furfural). The method uses a 4μL sample of bio-oil in a headspace vial (ca. 20mL). Complete evaporation of the compounds was achieved after seven minutes at 90°C. The method showed good precision and accuracy for methanol, ethanol, acetone and acetic acid. The recovery of furfural was low (74.3%). The results showed that the protocol can be applied for the determination of methanol, ethanol, acetone and acetic acid in bio-oil. Detection limits ranged from 0.13 to 0.16μg. Acetic acid was the dominant analyte in the heavy bio-oil and light bio-oil analysis (113. 3 and 85.1µgmg-1, respectively), followed by methanol, ethanol, and acetone. The polymerisation of furfural was suspected as the cause of its poor quantification.

Simultaneous pyrolysis and trimethylsilylation with N-methyl-(trimethylsilyl) trifluoroacetamide for the characterisation of lignocellulosic materials from kraft pulping

Abstract Simultaneous pyrolysis and trimethylsilylation (SPyT) with N-methyl-(trimethylsilyl)trifluoroacetamide (MSTFA) was used to characterise lignocellulosic materials from pine and eucalyptus obtained by kraft pulping. This approach protects the carboxyl groups and helps preserve the original structure of phenolic products during analytical pyrolysis, and so that pyrolysis and derivatisation occur simultaneously and the fragments of underivatised compounds are also silylatated. The SPyT products are representative for the structures present in carbohydrates and lignin of the investigated materials. The method is also suited to semi-quantitative evaluation also in terms of detection of condensed lignin structures in pulps and kraft lignins.

Evaluation of occurrence of NO3–, Coliform and atrazine in a karst aquifer, Colombo, PR

A vulnerabilidade de aquiferos do tipo carsticos a contaminacao por atividades agropecuarias ocorre em funcao de sua estrutura geomorfologica. No entanto, existem poucos estudos desta natureza no Brasil. O objetivo deste estudo foi avaliar a ocorrencia de nitrato, bacterias coliformes e atrazina em pocos rasos e profundos no aquifero carstico paranaense sob influencia de atividades agricolas. O estudo foi realizado em uma area de agricultura intensiva sobre aquifero carstico da bacia hidrografica do Alto Iguacu/Ribeira no municipio de Colombo-PR. As campanhas amostrais foram realizadas no periodo entre 2014 e 2015 em 15 pocos rasos e 7 pocos profundos, para analise bacteriologica, de NO3- e de atrazina na agua. A concentracao de NO3- nos pocos rasos variou entre 0,14 mg L-1 e 40,22 mg L-1. Nos pocos profundos, as concentracoes foram menores, entre 1,24 mg L-1 e 17,86 mg L-1. A analise de coliformes totais e fecais apresentou a mesma tendencia da presenca deNO3-. A atrazina foi detectada em 5 pocos rasos e 4 profundos. Propriedades fisico-quimicas da atrazina, assim como, as fraturas do aquifero carstico e alta condutividade hidraulica podem ser consideradas como fatores determinantes no destino deste pesticida.