Emulsified oil separation by bioadsorption: a sustainable proposal.

Oil emulsions are very stable, so both the treatment and the recovery of marine oil spills require expensive technologies, sometimes inefficient. Thus, studies of alternative methods for the treatment of oily effluents and phytoremediation are very important for sustainable development. The objective of this study was to use a chemically modified biomass of Salvinia sp. (SOH), for the removal of oil from oil-in-water emulsions. Initially, a chemical modification was carried out to remove interferences and to increase the adsorption capacity of the biomass. Physicochemical characterization tests were performed to understand the structure of the adsorbent produced as well as to verify changes going on the surface of the material. Adsorption tests were done, such as concentration variation, time, temperature and pH. The maximum adsorption capacity (qmax) of SOH was obtained in 15 min and was 574.86 mg g-1 in oil-in-salt water emulsion and 525.92 mg g-1, for oil-in-water emulsion. The isotherm model that best fitted was Freundlich model and for the kinetic model, the best fit was obtained with the intraparticle diffusion model. Thermodynamic studies indicate that SOH has physisorption, and the process is spontaneous and reversible.

Sex, Digital Devices, Social Media, and Social Isolation: A Study on Sexual Behavioral During COVID -19 Pandemic.

INTRODUCTION: Coronavirus (COVID-19) pandemic has caused social and economic damages. People have adapted to a new reality of physical distance. OBJECTIVE: The study aimed to assess the use of digital devices and social media, focusing on psychosocial and demographic factors of people´s sexual behavior during the pandemic. METHODS: A total of 1,357 Brazilian adults participated in a cross-sectional online survey. They were recruited through social media to obtain information regarding sexual behavior and the use of digital devices and social media. RESULTS: Digital devices and social media were used by 38.8% of the participants. Among the group that used technological devices, most claimed to have changed their sexual behavior, with 76.9% consuming more sexual content through movies or series. CONCLUSION: In a smaller group, technological resources appeared as an alternative for safer sex, reducing the risks of COVID-19 transmission.

Adsorption of indigo carmine on Pistia stratiotes dry biomass chemically modified.

Pistia stratiotes is a common aquatic plant of the northern region of the state of Rio de Janeiro, and its use as adsorbent material was studied in the present work. The preparation process included washing, drying, grinding, and acid activation. The sorption potential for removal of the indigo carmine dye from aqueous solutions was tested under various conditions, such as initial concentration, contact time, and temperature. The tests showed that the obtained biosorbent showed good performance for dye removal with a maximum capacity of 41.2 mg/g. The kinetic studies revealed that the pseudo-second-order equation provided the best fit of the experimental data. The Freundlich isotherm provided the best fit of the experimental sorption data for the system under study. The results obtained show that Pistia stratiotes has great potential to be used as biosorbent for the removal of dyes from aqueous solutions.