Polymers and Plastics, Fuel Technology, Colloid and Surface Chemistry, Waste Management and Disposal
128
Scopus Publications
Scopus Publications
Evaluation of the Influence of Antifoam Formulations on Asphaltene Aggregates Using AFM and SEM-EDS Mariana Teixeira Mendes, Andressa Oliveira dos Santos, Rafael Farias Perez, Osvaldo Karnitz Junior, Claudia Regina Elias Mansur Journal of Applied Polymer Science, 2026 Asphaltenes, naturally occurring surfactants in crude oil play a pivotal role in stabilizing oily foams during primary oil processing. Accordingly, understanding how antifoam formulations influence asphaltene aggregation is essential. This study investigates the effect of polydimethylsiloxane (PDMS) with varying molar masses on asphaltene organization using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). SEM provided morphological characterization of the asphaltene aggregates, showing that PDMS with different molar masses alters both the size and structure of these clusters. AFM offered complementary nanoscale insights, revealing how PDMS impacts the interfacial behavior of asphaltenes. The findings demonstrate that PDMS molar mass significantly affects the dispersion and aggregation of asphaltenes, highlighting its potential for enhancing additive performance in petroleum processing. Overall, this study advances the understanding of PDMS–asphaltene interactions and supports the development of more effective solutions for oil and gas separation in primary processing in the oil industry.
Performance of Carboxymethyl Starch and Chitosan as Green Scale Inhibitors for Calcite and Gypsum Precipitation Hugo N. S. Barros, Kaio A. B. Pereira, Matheus V. Oliveira, Luiz Antônio B. Rocha, Luiz C. M. Palermo, et al. Chemistryselect, 2025 Scale formation represents a significant problem in oil industry and results in a cost increase to maintain operations. The main reasons for this include the reduction in the fluid flow, the obstruction of pipelines, as well as accidents in more severe cases. However, many commercial chemistry inhibitors of inorganic scale are phosphate‐base, which has high toxicity to the environment. Therefore, biopolymers‐based scale inhibitors are alternatives and have been gaining ground in these applications, as they are abundant, low cost and environmentally friendly. In this study, the products derived from chitosan and starch were carboxymethylated, characterized, and evaluated for their inhibition of calcium sulphate precipitation by static efficiency tests and calcium carbonate by dynamic efficiency tests. The products were characterized by FTIR, H‐NMR, and TGA, whereas the crystals were analyzed using optical and scanning electron microscopy. The performance tests for the additives were conducted under simulated reservoir conditions, with temperatures of 70 and 80 °C and brine models. The standard calcium compatibility test was performed at 70 °C. The results showed that the chemical modification was successful and that the products demonstrated excellent compatibility with calcium standards. The performance tests showed high static efficiency, up to 95% for calcium sulphate, and the additives were approved in the dynamic protocol, CMCh and CMSt, with MIC values around 20–40 ppm and 10 ppm, respectively. The micrographs revealed morphological modifications that corroborated the performance results.
Application of Cassia Gum in Enhanced Oil Recovery Raíssa Takenaka Rodrigues Carvalho, Neimar Paulo de Freitas, Agatha Densy dos Santos Francisco, Luiz Carlos Palermo, Claudia Regina Elias Mansur ACS Polymers Au, 2025
Nanosystems with potential application as carriers for skin depigmenting actives Natalia Ruben Castro, Cristal Dos Santos C Pinto, Elisabete P Dos Santos, Claudia Regina E Mansur Nanotechnology, 2024 Hyperpigmentation is a skin disorder characterized by excessive production of melanin in the skin and includes dyschromias such as post-inflammatory hyperchromias, lentigens, melasma and chloasma. Topical products containing depigmenting agents offer a less aggressive treatment option for hyperpigmentation compared to methods like chemical peels and laser sessions. However, some of these agents can cause side effects such as redness and skin irritation. Encapsulating these actives in nanosystems shows promise in mitigating these effects and improving product safety and efficacy. In addition, nanocarriers have the ability to penetrate the skin, potentially allowing for targeted delivery of actives to the affected areas. The most commonly investigated nanosystems are nanoemulsions, vesicular nanosystems and nanoparticles, in which different materials can be used to generate different compositions in order to improve the properties of these nanocarriers. Nanocarriers have already been widely explored, but it is necessary to understand the evolution of these technologies when applied to the treatment of skin hyperchromias. Therefore, this literature review aims to present the state of the art over the last 15 years on the use of nanosystems as a potential strategy for encapsulating depigmenting actives for potential application in cosmetic products for skin hyperchromia. By providing a comprehensive overview of the latest research findings and technological advances, this article can contribute to improving the care and quality of life of people affected by this skin condition.
Production and Evaluation of Hydroxypropyl Starch as a Viscosifying Agent for Enhanced Oil Recovery Kelly Lúcia Nazareth Pinho de Aguiar, Karen de Sá Gomes, Matheus Ferreira da Silva Licht, Luiz Carlos Magalhães Palermo, Claudia Regina Elias Mansur Chemistryselect, 2024 In this study, starch was obtained from rice wastes and the maximum extraction yield was 90.95 %. Chemical modification reactions were carried out by hydroxypropylation to obtain a modified starch extract, named 005A, soluble in synthetic injection brine. Extract 005A had a modified starch concentration of 1.24 %, with a pseudoplastic rheological profile and viscosities of 325.54 cP and 121.03 cP at temperatures of 25 and 60 °C, respectively. The application of extract 005A was evaluated by injectivity/filterability tests, which indicated a good filtration rate and viscosity loss of 3.81 % when passing the fluid through the filtering membrane. Stability tests indicated that the 005A extract had a viscosity loss of 21.35 %, at the temperature of 60 °C, after 60 days. The application of this extract enabled additional mineral oil recovery of 12.19 % in simulated core flooding tests. Therefore, the extract of hydroxypropyl starch is a promising viscosifying agent for Enhanced Oil Recovery (EOR) fluids.
Microemulsified systems based on passion fruit oil as potential green corrosion inhibitors for carbon steel P110 in saline medium saturated with CO2 21st International Corrosion Congress Icc Intercorr Wco 2021, 2021
Nanosystems in photoprotection Cristal dos Santos Cerqueira Coutinho, Elisabete P. dos Santos, Claudia R. E. Mansur Journal of Nanoscience and Nanotechnology, 2015
Efficiency analysis of nanoemulsions systems containing silicone polyether as demulsifying and antifoaming agents for petroleum Nanoscale Science and Engineering Forum 2013 Core Programming Area at the 2013 Aiche Annual Meeting Global Challenges for Engineering A Sustainable Future, 2014
Development and evaluation of nanostructured formulations containing 8-methoxalen Pharmaceutical Discovery Development and Manufacturing Forum 2013 Core Programming Area at the 2013 Aiche Annual Meeting Global Challenges for Engineering A Sustainable Future, 2013
Removal of oil from oily waters by chitosan microspheres: Batch studies Environmental Division 2013 Core Programming Area at the 2013 Aiche Annual Meeting Global Challenges for Engineering A Sustainable Future, 2013
A study of asphaltene-resin interactions Luiz C. C. Marques, Juliana O. Pereira, André D. Bueno, Valdo S. Marques, Elizabete F. Lucas, et al. Journal of the Brazilian Chemical Society, 2012
