Nanoparticles are materials with special properties that can be applied in different fields, such as medicine, engineering, food industry and cosmetics. The contributions regarding the synthesis of different types of nanoparticles have allowed researchers to determine a special group of nanoparticles with key characteristics for several applications. Magnetite nanoparticles (Fe3O4) have attracted a significant amount of attention due to their ability to improve the properties of polymeric materials. For this reason, the development of novel/emerging large scale processes for the synthesis of nanomaterials is a great and important challenge. In this work, an environmental assessment of the large scale production of magnetite via coprecipitation was carried out with the aim to evaluate its potential impact on the environment at a processing capacity of 806.87 t/year of magnetite nanoparticles. The assessment was performed using a computer-aided tool based on the Waste Reduction Algorithm (WAR). This method allows us to quantify the impacts generated and classify them into eight different categories. The process does not generate any negative impacts that could harm the environment. This assessment allowed us to identify the applicability of the large scale production of magnetite nanoparticles from an environmental viewpoint.

Recently, exergy analysis has attracted great attention of the scientific community as an attractive tool for evaluating energetic efficiency of any process. In this work, the simulation of the amine treatment unit in a Latin-American refinery was performed in order to apply the exergy analysis tool to identify alternatives of improvement. The industrial amine treatment unit was simulated using Aspen plus software, which provided extended energy and mass balances. To calculate irreversibilities of the process and global exergy efficiencies per stages, the general methodological procedure of exergy analysis was used. To this end, physical and chemical exergies were found for compounds involved within the process. The values estimated for total irreversibilities, exergy of utilities, and exergy of wastes in the treatment of the sulfur-rich amine allowed us to analyze the stages that require reductions in waste generation and utility consumption. For a processing capacity of 72.08 t/h of rich amine, results revealed that the overall exergy efficiency was 83.81% and the total irreversibility was 1.69 × 105 MJ/h, where 23.6% corresponds to the total exergy by residues (3.98 × 104 MJ/h). The novel strategy to use exergy analysis for process optimization proved to be useful to detect critical stages and prioritize actions to improve.

In this study, the inherent safety analysis of large-scale production of chitosan microbeads modified with TiO2 nanoparticles was developed using the Inherent Safety Index (ISI) methodology. This topology was structured based on two main stages: (i) Green-based synthesis of TiO2 nanoparticles based on lemongrass oil extraction and titanium isopropoxide (TTIP) hydrolysis, and (ii) Chitosan gelation and modification with nanoparticles. Stage (i) is divided into two subprocesses for accomplishing TiO2 synthesis, lemongrass oil extraction and TiO2 production. The plant was designed to produce 2033 t/year of chitosan microbeads, taking crude chitosan, lemongrass, and TTIP as the primary raw materials. The process was evaluated through the ISI methodology to identify improvement opportunity areas based on a diagnosis of process risks. This work used industrial-scale process inventory data of the analyzed production process from mass and energy balances and the process operating conditions. The ISI method comprises the Chemical Inherent Safety Index (CSI) and Process Inherent Safety Index (PSI) to assess a whole chemical process from a holistic perspective, and for this process, it reflected a global score of 28. Specifically, CSI and PSI delivered scores of 16 and 12, respectively. The analysis showed that the most significant risks are related to TTIP handling and its physical-chemical properties due to its toxicity and flammability. Insights about this process′s safety performance were obtained, indicating higher risks than those from recommended standards.

A importância de melhorar os processos de transformação industrial para processos mais eficientes é parte dos desafios atuais. Específicamente, o desenvolvimento de processos mais eficientes na produção de biocombustíveis, onde os processos de reação e separação podem ser intensificados, é de grande interesse para reduzir o consumo de energia associado ao processo. No caso do Biodiesel, o processo é definido por uma reação química e pelos componentes associados ao processo, onde o estudo termoquímico busca desenvolver cálculos para o entendimento subsequente do processo de reação e purificação. Assim, a análise da mistura dos componentes usando o simulador de processo Aspen Plus V9® descreve o estudo termoquímico. O método termodinâmico UNIFAC-DMD foi utilizado para estimar os parâmetros binários de equilíbrio dos reagentes usando o simulador. Os aspectos analisados apresentam o comportamento dos componentes em diferentes condições de temperatura, o comportamento azeotrópico e as condições termoquímicas determinadas

Naphtha is an important distillation product of crude oil, and is used as a raw material for first-generation products such as ethylene, propylene, gasoline, xylene (BTX), and others. However, due to the different sources of crude oil, differences in naphtha composition impact the quality of conversion processes. Parameters such as pressure, charge flow, and temperature need to be adjusted for conversion efficiency. This work aims to compare naphtha samples from different origins, through the analysis of distillation curve (ASTM D86), density (ASTM D4052), total sulfur (ASTM D4294), and n-paraffins, iso-paraffins, olefins, naphthene, and aromatics (PIONA, ASTM D5134). Among these parameters evaluated in naphtha, the ones that showed the greatest correlation with the type of oil and its origin was the amount of total sulfur, number of aromatics, and paraffins. The three imported evaluated naphtha presented values greater than 200 mg/kg of total sulfur, aromatics above 9%w, and paraffins (P + I) below 76%w, while the national naphtha presented sulfur contents of at most 141 mg/kg, aromatics below 7%w, and paraffins (P + I) above 78%w. Finally, the study of this type of hydrocarbon enables the understanding of the needs of Latin American refineries and the world in relation to its treatment. National petrochemical companies have more difficulty in processing this product, causing an increase in naphtha importation by 108.51% from 2020/2021 in Brazil. Given this scenario, the Brazilian government should invest more in its petrochemical plants to reduce these imports, which, in the long term, would have a positive impact on the quality and value of naphtha byproducts.