Luiz Eduardo Pizarro Borges

In this work, the fresh seeds of Açaí (Euterpe oleracea Mart.), a rich lignin-cellulose residue, has been submitted to pyrolysis to produce a bio-oil like fuel. The pyrolysis reaction was carried out in a reactor of 143 L, operating in batch mode at 450 °C, 1.0 atmosphere. The morphology of the seeds of Açaí in nature and after pyrolysis process, were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The bio-oil and distillation fractions were physical-chemistry characterized by AOCS, ASTM, and ABNT/NBR methods for density, kinematic viscosity, acid value and refractive index. The chemical composition and qualitative analysis of chemical functions and/or groups present in bio-oil and distillation fractions were determined by GC-MS and FT-IR spectroscopy. The experimental data shows that bio-oil, a pyrolysis reaction liquid product, gas, H2O, and coke yields were 4.37% (wt.), 27.00, 33.63, and 35.00% (wt.), respectively. The bio-oil density and viscosity were 1.0468 g/cm3 and 162.96 mm²/s, respectively, with and acid value of 70.26 mg KOH/g. The GC-MS analysis shows that bio-oil is composed by 21.52% (wt.) hydrocarbons, and 78.48% (wt.) oxygenates (4.06% esters, 8.52% carboxylic acids, 3.53% ketones, 35.16% phenols, 20.52% cresols, 5.75% furans, and 0.91% (wt.) aldehydes. The distillation of bio-oil carried out in a laboratory scale column (Vigreux Column) according to the boiling temperature range of fossil fuels (gasoline, light kerosene, and kerosene). The distillation of bio-oil yielded gasoline, light kerosene, and kerosene-like fuel fractions of 16.16, 19.56, and 41.89% (wt.), respectively. The densities of gasoline, light kerosene, and kerosene-like fuel fractions were 0.9146, 0.9191, and 0.9816 g/cm3, respectively, while the kinematic viscosities were 1.457, 3.106, and 4.040 mm²/s, respectively, with acid values of 14.94, 61.08, and 64.78 mg KOH/g, increasing with boiling range temperature. The GC-MS analysis identified in gasoline, light kerosene, and kerosene-like fuel fractions 64.00%, 66.67%, and 19.87% (wt.) hydrocarbons. The pyrolysis has caused substantial changes on the morphological structure of Açaí seeds in nature by destructing the plant cell walls. The results of EDX show that carbon content increases from 79.28 to 89.98% (wt.), while that of oxygen decreases from 20.71 to 6.94% (wt.) at 450 °C. The results of XRD confirm the presence of 03 crystalline phases: graphite (C), cristobalite (SiO2), and quartz (SiO2), being the graphite the peak of high intensity (100%). The pyrolysis favors the formation of mineralogical phase graphite. The bio-adsorbent has been applied to selectively adsorb acetic acid from aqueous solutions, showing its ability to be applied as a bio-adsorbent.

In this work, the influence of temperature on the yield of reaction products (bio-oil, gas, H₂O, and coke), physicochemical properties (acid value, density, and kinematic viscosity) and chemical composition (hydrocarbons and oxygenates) of bio-oil obtained by pyrolysis of fresh Açaí (Euterpe oleracea Mart.) seeds, a rich lignin-cellulose residue, has been systematically investigated in technical scale. The pyrolysis reaction carried out in a reactor of 143 L, operating in batch mode at 350, 400, and 450 ºC, 1.0 atmosphere. The distillation of bio-oil carried out in a laboratory scale (Vigreux) column according to the boiling temperature range of fossil fuels. The bio-oil and distillation fractions were physical-chemistry characterized for density, kinematic viscosity, acid value and refractive index. The chemical composition and qualitative analysis of chemical functions and/or groups present in bio-oils were determined by GC-MS and FT-IR. The yields of bio-oil, H₂O and gas varied between 2.0 and 4.39% (wt.), 26.58 and 29.39% (wt.), and 18.76 and 30.56% (wt.), respectively, increasing with process temperature, while that of solid phase (coke) varied between 35.67 and 52.67% (wt.), decreasing with temperature. The distillation of bio-oil yielded gasoline, light kerosene, and kerosene-like fuel fractions of 16.16, 19.56, and 41.89% (wt.), respectively. The bio-oil densities and kinematic viscosities ranged between 1.0236 and 1.0468 g/cm³, and 57.22 and 68.34 mm²/s, respectively, increasing with temperature, while bio-oil acid values varied between 70.26 and 92.87 mg KOH/g, decreasing with temperature. The densities of gasoline, light kerosene, and kerosene-like fuel fractions were 0.9146, 0.9191, and 0.9816 g/cm³, respectively, while the kinematic viscosities were 1.457, 3.106, and 4.040 mm²/s, respectively, with acid values of 14.94, 61.08, and 64.78 mg KOH/g, increasing with boiling range temperature. The FT-IR analysis identified in bio-oil chemical functions characteristics of hydrocarbons (alkanes, alkenes, and aromatics) and oxygenates (phenols, cresols, ketones, esters, carboxylic acids, aldehydes, and furans). The GC-MS analysis identified hydrocarbons and oxygenates as major chemical compounds in bio-oil, with chemical composition strongly dependent on pyrolysis temperature. The concentration of hydrocarbons in bio-oil varied between 13.505 and 21.542% (area.), increasing with temperature, while that of oxygenates varied between 78.458 and 86.495% (area.), decreasing with pyrolysis temperature. The composition of alkanes, alkenes, and aromatics increase with temperature, showing that higher temperatures favor the formation of hydrocarbons.

This study aims to systematically investigate the combined effect of chemical activation of açaí seeds (Euterpe oleracea Mart.), with an aqueous sodium hydroxide (NaOH) solution at 2 mol·L⁻¹, and process temperature by pyrolysis of alkaline activated açaí seeds on the yield of reaction products (bio-oil, gas, H₂O, and biochar), physicochemical properties (acid value, density, and kinematic viscosity) and chemical composition (hydrocarbons and oxygenates) of bio-oil. Catalytic pyrolysis was carried out in a 143 L reactor at temperatures of 350 °C, 400 °C, and 450 °C, 1.0 atmosphere, operating in batch mode. The NaOH activation played a crucial role in modifying the thermal degradation pathway of the biomass, promoting the formation of specific chemical structures and altering the product yields. NaOH acted as a catalyst, enhancing the deoxygenation of the biomass and stimulating the formation of hydrocarbons. As a result, the yields of bio-oil, water, biochar, and gas varied from 5.77 to 7.20% (by mass), 14.90 to 19.77% (by mass), 41 to 54% (by mass), and 25.33 to 32.03%, respectively, influenced by the increase in temperature. FT-IR analyses indicated the presence of characteristic chemical functions of hydrocarbons (alkanes, alkenes, and aromatics) and oxygenated compounds (phenols, cresols, ketones, esters, carboxylic acids, aldehydes, and furans), with an intensification of hydrocarbon signals at higher temperatures. GC-MS analysis identified hydrocarbons and oxygenated compounds as the main chemical classes in the bio-oil, showing a strong dependence on pyrolysis temperature. It was observed that hydrocarbon concentration in bio-oil increased from 49.7% to 57.88% (area) with increasing temperature, while the concentration of oxygenated compounds decreased from 13.88% to 6.69% (area), demonstrating that NaOH activation, combined with temperature elevation, favors the formation of hydrocarbons and the reduction of oxygenated compounds, thereby improving the quality of the produced bio-oil.

O gás de xisto tem sido identificado como um potencial contribuinte para a diversificação energética do Brasil, porém seu desenvolvimento não avançou além de iniciativas exploratórias. Este estudo investiga o desenvolvimento do gás de xisto e a dinâmica regulatória no Brasil entre 2013 e 2026, com foco na Bacia Potiguar, a fim de identificar as restrições sistêmicas nas dimensões operacional, tecnológica, territorial e regulatória. Utilizando uma estrutura de Engenharia de Produção integrada com análises territorial e regulatória, o estudo combina dados de patentes, mapeamento institucional, avaliações ambientais e diagnósticos da cadeia de suprimentos. Os resultados indicam que as principais restrições não são geológicas, mas sim operacionais, tecnológicas, territoriais e regulatórias. Na Bacia Potiguar, semiárida, a alta demanda hídrica para fraturamento hidráulico (15.000–45.000 m³ por poço) entra em conflito estrutural com a disponibilidade hídrica local e com outros usos concorrentes. A prospecção tecnológica, no entanto, revela uma trajetória de inovação emergente em tecnologias de fraturamento com baixo ou nenhum consumo de água, bem como sistemas avançados de monitoramento baseados em nanotecnologia, que podem mitigar parcialmente essas restrições no futuro. Apesar desses desenvolvimentos, as condições industriais atuais permanecem insuficientes para a implantação em larga escala. O estudo conclui que a estagnação do gás de xisto no Brasil é impulsionada principalmente pelo desalinhamento sistêmico nas cadeias de suprimentos, na governança territorial e na localização tecnológica. Sem uma ação coordenada nessas dimensões, é provável que o gás de xisto permaneça estruturalmente limitado dentro da matriz energética nacional. As descobertas contribuem para o desenvolvimento de estruturas de governança multicritério para sistemas de energia não convencional.

O desenvolvimento de gás de xisto em regiões ambientalmente sensíveis e institucionalmente fragmentadas opera como um sistema sociotécnico dominado por retroalimentação, no qual as dinâmicas de produção, ambientais e de governança coevoluem por meio de estruturas causais assimétricas e temporalmente diferenciadas. Este estudo adota uma perspectiva de engenharia de produção combinada com uma abordagem qualitativa de dinâmica de sistemas para examinar a Bacia do Paraná, com foco na arquitetura de retroalimentação subjacente que molda o comportamento do sistema, em vez de simulação preditiva. A análise identifica um mecanismo de produção reforçador impulsionado pela expansão dependente da perfuração e pelo declínio da produtividade dos poços, gerando um regime de crescimento estruturalmente restrito, caracterizado por requisitos contínuos de reinvestimento. Essa dinâmica reforçadora é progressivamente contrabalançada por uma hierarquia de retroalimentações balanceadoras: declínio da produtividade técnica, pressão ambiental cumulativa e respostas regulatórias endógenas. Os resultados mostram que o comportamento do sistema é fundamentalmente moldado por assimetrias temporais nos ciclos de retroalimentação. As dinâmicas de produção reforçadoras operam rapidamente, enquanto a acumulação ambiental e as respostas de governança são retardadas, produzindo uma janela estrutural na qual a expansão precede a ativação das restrições. As variáveis ambientais atuam como estoques cumulativos do sistema, conectando a atividade de produção à pressão regulatória, enquanto a governança emerge endogenamente por meio de respostas adaptativas, porém tardias, a sinais ambientais e sociopolíticos. A interação entre os subsistemas gera uma estrutura interdomínio fortemente acoplada, na qual a expansão da produção, a degradação ambiental e a adaptação regulatória remodelam continuamente as trajetórias do sistema. Esse acoplamento produz um comportamento não linear e dependente da trajetória, no qual os resultados de sustentabilidade emergem da dominância do feedback, em vez do planejamento de políticas exógenas. Ao formalizar essas interações por meio de uma estrutura de circuito causal, o estudo fornece uma interpretação estrutural da governança do gás de xisto como uma propriedade emergente da interação com sistemas de feedback. As descobertas destacam que as compensações de sustentabilidade não são incidentais, mas estruturalmente incorporadas na arquitetura do sistema, com implicações para a governança antecipatória e o planejamento da transição energética em regiões emergentes de gás de xisto.

In this study, the influence of chemical impregnation with an aqueous sodium hydroxide (NaOH) solution at 2 mol·L⁻¹, as well as process temperature, was systematically investigated at a pilot scale on the yield of pyrolysis products (bio-oil, gas, water, and biochar), as well as on the physi-cochemical properties (acid value, density, and kinematic viscosity) and chemical composition (hydrocarbons and oxygenated compounds) of the bio-oil obtained from açaí seeds (Euterpe oleracea Mart.). The pyrolysis reactions were carried out in a 143 L batch reactor at temperatures of 350 °C, 400 °C, and 450 °C under a pressure of 1.0 atmosphere. The NaOH impregnation played a crucial role in modifying the thermal degradation pathway of the biomass, promoting the formation of specific chemical structures and altering the product yields. NaOH acted as a catalyst, enhancing the deoxygenation of the biomass and stimulating the formation of hydrocarbons. As a result, the yields of bio-oil, water, biochar, and gas varied from 5.77 to 7.20% (by mass), 14.90 to 19.77% (by mass), 41 to 54% (by mass), and 25.33 to 32.03%, respectively, influenced by the increase in temperature. FT-IR analyses indicated the presence of characteristic chemical functions of hydrocarbons (alkanes, alkenes, and aromatics) and oxygenated compounds (phenols, cresols, ketones, esters, carboxylic acids, aldehydes, and furans), with an intensification of hydrocarbon signals at higher temperatures. GC-MS analysis confirmed hydrocarbons and oxygenated compounds as the main chemical classes in the bio-oil, showing a strong dependence on pyrolysis temperature. It was observed that the hydrocarbon concentration increased from 49.7% to 57.88% (area) with rising temperature, while the concentration of oxygenated compounds decreased from 13.88% to 6.69% (area), demonstrating that NaOH impregnation, combined with temperature elevation, favors the formation of hydrocarbons and the reduction of oxygenated compounds, thereby improving the quality of the produced bio-oil.

This study examines the chemical recycling of polymethylmethacrylate (PMMA) dental waste in semi-batch fixed-bed reactors via pyrolysis, aiming to convert this waste into the valuable monomer methyl methacrylate (MMA). First, the effect of temperature is analyzed in a laboratory-scale (30 g) semi-batch reactor at 350, 400 and 450 °C. In order to visualize the combined effect of temperature and increase in bed volume, experiments conducted at 350 °C in the laboratory (30 g) and on a pilot scale (20 kg) are compared. Experiments conducted at 475°C on technical and pilot scales are also compared to elucidate this behavior. A detailed process analysis is presented, considering different experiments conducted in a semi-batch technical-scale reactor. Experiments were conducted in a 2 L reactor at temperatures of 425 °C, 450 °C and 475 °C to understand the effects of heating rate and temperature on product yield and composition. The results show that at 425 °C, MMA was the primary liquid component, with minimal by-products, suggesting that lower temperatures enhance monomer recovery. Higher temperatures, however, increased gas yields and reduced MMA yield due to intensified thermal cracking. This study also highlights that char formation and non-condensable gases increase with the reactor scale, indicating that heat transfer limitations can influence MMA purity and yield. These findings emphasize that for effective MMA recovery, lower temperatures and controlled heating rates are optimal, especially in larger reactors where heat transfer issues are more prominent. This research study contributes to scaling up PMMA recycling processes, supporting industrial applications to achieve efficient monomer recovery from waste.

This study aims to assess the by-products generated through the thermal and catalytic pyrolysis of the organic matter and paper fractions of municipal solid waste (MSW) in different socioeconomic regions, through the yields of reaction products (bio-oil, biochar, H₂O, and gas), acid value and chemical composition of bio-oils, and characterization of biochar, on a laboratory scale. The organic matter and paper segregated from the gravimetric composition of the total waste sample were subjected to drying, crushing, and sieving pre-treatment. The experiments were carried out at 450 °C and 1.0 atmosphere, and at 400 °C and 475 °C and 1.0 atmosphere, using a basic catalyst, Ca(OH)₂, at 10.0% by mass, in discontinuous mode. The bio-oil was characterized by acidity value and the chemical functions present in the bio-oil identified by FT-IR, NMR, and composition by GC-MS. The biochar was characterized by SEM/EDS and XRD. The bio-oil yield increased with the addition of the catalyst and the pyrolysis temperature. For catalytic pyrolysis, bio-char and gas yields increased slightly with the Ca(OH)₂ content, while bio-oil and H₂O phases remained constant. The GC-MS of the liquid reaction products identified the presence of hydrocarbons and oxygenates, as well as nitrogen-containing compounds, including amides and amines. The acidity of the bio-oil decreased with the addition of the basic catalyst in the process. The concentration of hydrocarbons in the bio-oil appeared with the addition of the catalyst in the catalytic pyrolysis process as the catalytic deoxygenation of fatty acid molecules occurred, through decarboxylation/decarbonylation, producing aliphatic and aromatic hydrocarbons, introducing the basic catalyst into the thermal process.

Waste animal fat (WAF) can be converted to distillate fractions similar to petroleum solvents and used as solvents via pyrolysis and fractional distillation. Pyrolysis oil from triglyceride materials presents adequate viscosity and volatility, compared to petroleum fuels, but shows acid values between 60–140 mg KOH/g, impeding its direct use as biofuels without considerable purification of its distillates. Fractional distillation can be applied for the purification of bio-oil, but only a few studies accurately describe the process. The purpose of this study was to evaluate the effect of temperature in the conversion of waste animal fat into fuel-like fractions by pyrolysis and fractional distillation in a semi-batch stirred bed reactor (2 L) according to reaction time. Waste animal fat was extracted (rendering) from disposed meat cuts obtained from butcher shops and pyrolyzed in a stainless-steel stirred bed reactor operating in semi-batch mode at 400–500 °C. The obtained liquid fraction was separated according to reaction time. The pyrolysis bio-oil at 400 °C was separated into four distinct fractions (gasoline, kerosene, diesel, and heavy phase) by fractional distillation with reflux. The bio-oil and distillate fractions were analyzed by density, kinematic viscosity, acid value, and chemical composition by gas chromatography coupled to mass spectra (GC-MS). The results show that, for semi-batch reactors with no inert gas flow, higher temperature is associated with low residence time, reducing the conversion of fatty acids to hydrocarbons. The distillate fractions were tested in a common application not sensible to the fatty acid concentration as a diluent in the preparation of diluted asphalt cutback for the priming of base pavements in road construction. Kerosene and diesel fractions can be successfully applied in the preparation of asphalt cutbacks, even with a high acid value.

This study explored the adsorption of carboxylic acids, especially free fatty acids (FFAs), present in biofuel (distilled fractions of bio-oil such as gasoline-like hydrocarbons, kerosene-like hydrocarbons, and diesel-like hydrocarbons) using red-mud-based adsorbents. The red mud was thermally activated at 40 °C and 600 °C and chemically activated with 0.25M, 1M, and 2M HCl. Analytical techniques were used to characterize the adsorbents’ properties. At the same time, the study examined factors like feed type, adsorbents, FFA contents, adsorbent percentage, activation temperature, acid solution concentration, and contact time to assess adsorption efficiency. The characterization results indicated that chemical activation with 0.25M HCl significantly increased the surface area to 84.3290 m²/g, surpassing that of the thermally activated samples (35.2450 m²/g at 400 °C). Adsorption experiments demonstrated that all chemically activated samples, with 5% adsorbent, adsorbed over 2000 mg of FFAs per gram of adsorbent, with CARM-1M HCl achieving 100% removal of acids from gasoline-like hydrocarbons. Kinetic modeling showed that the pseudo-second-order model best represented the adsorption data, as evidenced by high R² values and close agreement between the experimental and calculated q_e values. Therefore, adsorption with chemically activated red mud efficiently deacidifies biofuels, providing a cost-effective and promising approach for their upgrading.