Valorization of bio-alcohols into added value chemicals

The present research work focused on the valorisation and upgrading of bio-ethanol over heterogeneous catalysts in a lab-scale continuous gas-flow system. In the Unibo laboratories, catalytic tests have been carried out in the temperature range 300-600°C by feeding an ethanol/He mixture in the reactor. After choosing the reaction conditions, ion-exchanged hydroxyapatite with transition metals (i.e., Fe, Cu) and alkaline earth metal (i.e., Sr) have been synthesized and tested. The Sr-HAP catalyst led to the formation of a complex reaction mixture the composition of which need further optimization in order to fill the requisite to be used as fuel-blend. Then, some zirconium-oxide based catalysts have been prepared through two different methods, precipitation and hydrothermal, by varying some synthetic parameters (i.e., pH, the nature of the base) and by adding a transition metal as dopant agent (i.e., Ti and Y). The presence of a dopant into the zirconia structure favoured the stabilization of the tetragonal or cubic phase against the monoclinic one. Interestingly, 5%mol Ti-doped zirconia exhibited a different catalytic behaviour yielding diethyl ether as major product at 300°C, while all the others samples produced mainly ethylene. Then, the effect of acid-base properties of sepiolite, using alkali metals (i.e., Na, K, Cs) with different metal loading (i.e., 2, 4, 5, 7, 14 wt%) as promoters, and of the redox properties of sepiolite-supported CuO or NiO, on the catalytic conversion of ethanol into n-butanol has been investigated. Thermal treated sepiolite samples mainly acted as acid catalyst, yielding preferentially the dehydration products of ethanol (ethylene and diethyl ether). Best results in terms of activity (ethanol conversion, 59%) and n-butanol selectivity (30%) where obtained at 400ºC and a contact time, W/F, of 2 g/mL·s over the catalyst consisting of sepiolite calcined at 500ºC modified with 7 wt% of cesium.

Synergies among safety and security in the prevention of major accidents related to dangerous substances

Historical evidence shows that chemical, process, and Oil&Gas facilities where dangerous substances are stored or handled are target of deliberate malicious attacks (security attacks) aiming at interfering with normal operations. Physical attacks and cyber-attacks may generate events with consequences on people, property, and the surrounding environment that are comparable to those of major accidents caused by safety-related causes. The security aspects of these facilities are commonly addressed using Security Vulnerability/Risk Assessment (SVA/SRA) methodologies. Most of these methodologies are semi-quantitative and non-systematic approaches that strongly rely on expert judgment, leading to security assessments that are not reproducible. Moreover, they do not consider the synergies with the safety domain. The present 3-year research is aimed at filling the gap outlined by providing knowledge on security attacks, as well as rigorous and systematic methods supporting existing SVA/SRA studies suitable for the chemical, process, and Oil&Gas industry. The different nature of cyber and physical attacks resulted in the development of different methods for the two domains. The first part of the research was devoted to the development and statistical analysis of security databases that allowed to develop new knowledge and lessons learnt on security threats. Based on the obtained background, a Bow-Tie based procedure and two reverse-HazOp based methodologies were developed as hazard identification approaches for physical and cyber threats respectively. To support the quantitative estimation of the security risk, a quantitative procedure based on the Bayesian Network was developed allowing to calculate the probability of success of physical security attacks. All the developed methods have been applied to case studies addressing chemical, process and Oil&Gas facilities (offshore and onshore) proving the quality of the results that can be achieved in improving site security. Furthermore, the outcomes achieved allow to step forward in developing synergies and promoting integration among safety and security management.

Electrochemical oxidation of Kraft and Dealkaline lignin to produce value-added chemicals on Nickel electrocatalysts

One of the most important scientific and environmental issues is reducing global dependence on fossil sources and one of the solutions is to use biomass as feedstock. In particular, the use of lignocellulosic biomass to obtain molecules with considerable commercial importance is gaining more and more interest. Lignin, the most recalcitrant part of lignocellulosic biomass, is a valuable source of sustainable and renewable aromatic molecules, currently produced from petrochemical processes. Vanillin, one of the most important aromatic aldehydes on an industrial level, can be obtained through catalytic lignin oxidation. An alternative to the conventional catalytic oxidation process is the electro-catalytic process, which can be carried out at ambient temperature and pressure, using water as solvent, and it can be considered as a renewable energy storage. In this thesis, the electrocatalytic oxidation of Kraft and Dealkaline lignin in NaOH was investigated over Ni foam catalysts. The effect of the reaction parameters (i.e. time, applied potential, lignin concentration, NaOH concentration, and temperature) on the yields of vanillin and other valuable products was evaluated. After the screening of the reaction conditions, a systematic study of the contribution of the homogeneous reaction (lignin depolymerization due to the basic solvent) to the yield of the product was accomplished. Finally, considering the obtained results, an alternative reaction procedure was proposed.

Studio di fattibilità per la valorizzazione di reflui liquidi in un impianto di produzione di fine chemicals

Il progetto di tesi è stato svolto all’interno della divisione logistica dello stabilimento BASF Italia s.p.a. situato a Pontecchio Marconi (BO). L’elaborato tratta lo studio di fattibilità per la valorizzazione di reflui liquidi in un impianto di produzione di fine chemicals volto principalmente al miglioramento della separazione tra liquidi immiscibili all’interno delle cisterne del parco reflui del sito. La prima fase dello studio si è concentrata nella valutazione dello stato dell’arte nell’attuale gestione dei reflui in sito, che ha visto la sua prosecuzione naturale nel campionamento degli stessi per la caratterizzazione chimico-fisica. A seguito dello screening tecnologico e in funzione dei risultati ottenuti dalle analisi, sono stati individuati i processi più idonei per la finalità descritta. Infine sono stati contattati alcuni fornitori per svolgere delle prove con impianti pilota con l’obiettivo di ricavare dei risultati rappresentativi di un processo industriale. Lo studio di fattibilità si è concluso con il confronto tra le soluzioni individuate, evidenziando i diversi aspetti di carattere tecnico-economico-ambientale e illustrando gli svantaggi e i vantaggi di ognuna delle tecnologie.

The Crosslinking Degree Controls The Mechanical, Rheological, And Swelling Properties Of Hyaluronic Acid Microparticles.

Viscosupplements, used for treating joint and cartilage diseases, restore the rheological properties of synovial fluid, regulate joint homeostasis and act as scaffolds for cell growth and tissue regeneration. Most viscosupplements are hydrogels composed of hyaluronic acid (HA) microparticles suspended in fluid HA. These microparticles are crosslinked with chemicals to assure their stability against enzyme degradation and to prolong the action of the viscosupplement. However, the crosslinking also modifies the mechanical, swelling and rheological properties of the HA microparticle hydrogels, with consequences on the effectiveness of the application. The aim of this study is to correlate the crosslinking degree (CD) with these properties to achieve modulation of HA/DVS microparticles through CD control. Because divinyl sulfone (DVS) is the usual crosslinker of HA in viscosupplements, we examined the effects of CD by preparing HA microparticles at 1:1, 2:1, 3:1, and 5:1 HA/DVS mass ratios. The CD was calculated from inductively coupled plasma spectrometry data. HA microparticles were previously sized to a mean diameter of 87.5 µm. Higher CD increased the viscoelasticity and the extrusion force and reduced the swelling of the HA microparticle hydrogels, which also showed Newtonian pseudoplastic behavior and were classified as covalent weak. The hydrogels were not cytotoxic to fibroblasts according to an MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2014.

Direct And Non-destructive Proof Of Authenticity For The 2nd Generation Of Brazilian Real Banknotes Via Easy Ambient Sonic Spray Ionization Mass Spectrometry.

Using a desorption/ionization technique, easy ambient sonic-spray ionization coupled to mass spectrometry (EASI-MS), documents related to the 2nd generation of Brazilian Real currency (R$) were screened in the positive ion mode for authenticity based on chemical profiles obtained directly from the banknote surface. Characteristic profiles were observed for authentic, seized suspect counterfeit and counterfeited homemade banknotes from inkjet and laserjet printers. The chemicals in the authentic banknotes' surface were detected via a few minor sets of ions, namely from the plasticizers bis(2-ethylhexyl)phthalate (DEHP) and dibutyl phthalate (DBP), most likely related to the official offset printing process, and other common quaternary ammonium cations, presenting a similar chemical profile to 1st-generation R$. The seized suspect counterfeit banknotes, however, displayed abundant diagnostic ions in the m/z 400-800 range due to the presence of oligomers. High-accuracy FT-ICR MS analysis enabled molecular formula assignment for each ion. The ions were separated by 44 m/z, which enabled their characterization as Surfynol® 4XX (S4XX, XX=40, 65, and 85), wherein increasing XX values indicate increasing amounts of ethoxylation on a backbone of 2,4,7,9-tetramethyl-5-decyne-4,7-diol (Surfynol® 104). Sodiated triethylene glycol monobutyl ether (TBG) of m/z 229 (C10H22O4Na) was also identified in the seized counterfeit banknotes via EASI(+) FT-ICR MS. Surfynol® and TBG are constituents of inks used for inkjet printing.

Removal Of Glyphosate Herbicide From Water Using Biopolymer Membranes.

Enormous amounts of pesticides are manufactured and used worldwide, some of which reach soils and aquatic systems. Glyphosate is a non-selective herbicide that is effective against all types of weeds and has been used for many years. It can therefore be found as a contaminant in water, and procedures are required for its removal. This work investigates the use of biopolymeric membranes prepared with chitosan (CS), alginate (AG), and a chitosan/alginate combination (CS/AG) for the adsorption of glyphosate present in water samples. The adsorption of glyphosate by the different membranes was investigated using the pseudo-first order and pseudo-second order kinetic models, as well as the Langmuir and Freundlich isotherm models. The membranes were characterized regarding membrane solubility, swelling, mechanical, chemical and morphological properties. The results of kinetics experiments showed that adsorption equilibrium was reached within 4 h and that the CS membrane presented the best adsorption (10.88 mg of glyphosate/g of membrane), followed by the CS/AG bilayer (8.70 mg of glyphosate/g of membrane). The AG membrane did not show any adsorption capacity for this herbicide. The pseudo-second order model provided good fits to the glyphosate adsorption data on CS and CS/AG membranes, with high correlation coefficient values. Glyphosate adsorption by the membranes could be fitted by the Freundlich isotherm model. There was a high affinity between glyphosate and the CS membrane and moderate affinity in the case of the CS/AG membrane. Physico-chemical characterization of the membranes showed low values of solubility in water, indicating that the membranes are stable and not soluble in water. The SEM and AFM analysis showed evidence of the presence of glyphosate on CS membranes and on chitosan face on CS/AG membranes. The results showed that the glyphosate herbicide can be adsorbed by chitosan membranes and the proposed membrane-based methodology was successfully used to treat a water sample contaminated with glyphosate. Biopolymer membranes therefore potentially offer a versatile method to eliminate agricultural chemicals from water supplies.

Histopathological Alterations In The Prostates Of Mongolian Gerbils Exposed To A High-fat Diet And Di-n-butyl Phthalate Individually Or In Combination.

Both high-fat diet and exposure to endocrine-disrupting chemicals have been implicated in susceptibility to pathological prostate lesions, but the consequences of combining the two have not yet been examined. We evaluated the effects of gestational and postnatal exposure to a high-fat diet (20% fat) and low doses of di-n-butyl phthalate (DBP; 5mg/kg/day), individually or in combination, on the tissue response and incidence of pathological lesions in the ventral prostate of adult gerbils. Continuous intake of a high-fat diet caused dyslipidemia, hypertrophy, and promoted the development of inflammatory, premalignant and malignant prostate lesions, even in the absence of obesity. Life-time DBP exposure was obesogenic and dyslipidemic and increased the incidence of premalignant prostate lesions. Combined exposure to DBP and a high-fat diet also caused prostate hypertrophy, but the effects were less severe than those of individual treatments; combined exposure neither induced an inflammatory response nor altered serum lipid content.

Interferentes endócrinos no ambiente

Although the hypothesis that environmental chemicals may exhibit endocrine disrupting effects is not new, the issue has been a growing level of concern due to reports of increased incidences of endocrine-related disease in humans, including declining male fertility, and more significantly, to adverse physiological effects observed in wildlife where cause and effect relationships are more evident. The list of endocrine disrupting chemicals (EDCs) includes a range of anthropogenic compounds, phytoestrogens, naturally occurring sex steroids and synthetic estrogens. Within the aquatic environment, the presence of EDCs has concerned many scientists and water quality regulators. Discharge of effluents from treatment facilities is likely to be a significant source of input of contaminants to many systems, and the potential for concentration of hydrophilic compounds and transformation products within sludges has implications for their disposal. Then, understanding the processes and the fate of EDCs on the environment, as well as the mechanisms of endocrine disruption, may facilitate controlling or limiting exposure of both humans and the environment to these compounds.

Cutinases fúngicas: propriedades e aplicações industriais

Cutinases (EC 3.1.1.74) are also known as cutin hidrolases. These enzymes share catalytic properties of lipases and esterases, presenting a unique feature of being active regardless the presence of an oil-water interface, making them interesting as biocatalysts in several industrial processes involving hydrolysis, esterification and trans-esterification reactions. They are also active in different reaction media, allowing their applications in different areas such as food industry, cosmetics, fine chemicals, pesticide and insecticide degradation, treatment and laundry of fiber textiles and polymer chemistry. The present review describes the characteristics, potential applications and new perspectives for these enzymes.

Definição de shelf life para produtos químicos: a importância de um guia de estabilidade específico para o segmento

The chemical industries worldwide are passing through a very particular moment of re-adaptation due to the implementation of an European regulation called, Registration, Evaluation, Authorization and Restriction of Chemicals (REACH). In Brazil, the Brazilian Chemical Industry needs urgently a specific guide of chemical products stability. The main purpose of this work is to present a proposal of a guide of stability for chemical products based on the reference guides of the International Conference on Harmonization (ICH). Thus, this work proposes an innovation in terms of methodology which will be useful for shelf life definition purpose for chemical industry products.

Harmonização e classificação toxicológica de agrotóxicos em 1992 no Brasil e a necessidade de prever os impactos da futura implantação do GHS

Em 1992, o Brasil modificou seus critérios de classificação toxicológica de agrotóxicos adequando-os à recomendação de classificação de periculosidade da Organização Mundial da Saúde (OMS). Em 2002, o Sistema Globalmente Harmonizado de Classificação e Rotulagem de Produtos Químicos (GHS) foi adotado pela Organização das Nações Unidas. Em decorrência, a OMS está adequando ao GHS sua recomendação de classificação de agrotóxicos, o que também deverá ser feito pelo Brasil. Considerou-se oportuno estimar o impacto da alteração de critérios, ocorrida em 1992, na reclassificação toxicológica dos produtos comerciais que se encontravam registrados na ocasião. Encontrou-se que 58,6% do total dos agrotóxicos então registrados (74,9% das formulações líquidas e 31,0% das sólidas) podem ter sofrido reclassificação para classes toxicológicas consideradas de me-nor periculosidade, sofrendo mudanças na comunicação de riscos expressa na rotulagem. Isto pode ter ocasionado conseqüências negativas devido a confusões de interpretação pelos agricultores. Nos países que já dispõem de sistemas de classificação de periculosidade de agrotóxicos, como o Brasil, recomenda-se estimar, antes da implantação, os impactos das mudanças que poderão decorrer da adoção do GHS.

Hábitos relacionados ao descarte pós-consumo de aparelhos e baterias de telefones celulares em uma comunidade acadêmica

Cada vez mais a sociedade contemporânea incorpora em seu cotidiano equipamentos elétricos e eletrônicos, muitos deles contendo substâncias perigosas, que representam ameaças ao meio ambiente e riscos à saúde humana. Este artigo apresenta os resultados de uma pesquisa exploratória com o objetivo de relacionar comportamento de descarte pós-consumo de aparelhos e baterias de celulares, em um grupo de consumidores de telefonia móvel, que tem proximidade em seu cotidiano de trabalho e de estudo com informações sobre saúde pública e ambiental. Os resultados da pesquisa indicam que informação pode aproximar as pessoas do problema, porém não levam por si só à produção de alterações significativas sobre o que e como fazer com o descarte pós-consumo. Os participantes do estudo possibilitaram identificar, que além da informação e acesso a coletores específicos, outros aspectos e critérios pessoais ou coletivos interferem no procedimento de descarte: percepção sobre risco, valor econômico disponibilizado na compra do aparelho e vínculos afetivos, entre outros. Esses fatores podem produzir diferentes respostas dos usuários sobre como lidar com as inovações tecnológicas de uso pessoal.

Harmonização e classificação de periculosidade de agrotóxicos: impactos na classificação toxicológica, Brasil, 1992

Em 1992 o Brasil modificou seus critérios de classificação toxicológica de agrotóxicos adequando-os à recomendação de classificação de periculosidade da Organização Mundial da Saúde (OMS). Em 2002, o Sistema Globalmente Harmonizado de Classificação e Rotulagem de Produtos Químicos (GHS) foi adotado pela Organização das Nações Unidas. Em decorrência, a OMS está adequando ao GHS sua recomendação de classificação de agrotóxicos, o que também deverá ser feito pelo Brasil. Considerou-se oportuno estimar o impacto da alteração de critérios, ocorrida em 1992, na reclassificação toxicológica dos produtos comerciais que se encontravam registrados na ocasião. Encontrou-se que 58,6% do total dos agrotóxicos então registrados (74,9% das formulações líquidas e 31,0% das sólidas) podem ter sofrido reclassificação para Classes Toxicológicas consideradas de menor periculosidade, sofrendo mudanças na comunicação de riscos expressa na rotulagem. Isto pode ter ocasionado conseqüências negativas devido à confusões de interpretação pelos agricultores. Nos países que já dispõem de sistemas de classificação de periculosidade de agrotóxicos, como o Brasil, recomenda-se estimar, antes da implantação, os impactos das mudanças que poderão decorrer da adoção do GHS