The rise of emerging contaminants in waters challenges the scientific community and water treatment stakeholders to design remediation techniques that are simple, practical, inexpensive, effective, and environmentally friendly. Emerging contaminants include antibiotics, hormones, illicit drugs, endocrine disruptors, cosmetics, personal care products, pesticides, surfactants, industrial products, microplastics, nanoparticles, and nanomaterials. Removing those contaminants is not easy because classical wastewater treatment systems are not designed to handle emerging contaminants, and contaminants often occur as traces in complex organo-mineral mixtures. Here, we review advanced treatments for the removal of emerging contaminants in wastewater, with focus on adsorption-oriented processes using non-conventional adsorbents such as cyclo-dextrin polymers, metal-organic frameworks, molecularly imprinted polymers, chitosan, and nanocellulose. We describe biological-based technologies for the degradation and removal of emerging contaminants. Then, we present advanced oxida-tion processes as the most promising strategies because of their simplicity and efficiency.

Water contamination by emerging contaminants is increasing in the context of rising urbanization, industrialization, and agriculture production. Emerging contaminants refers to contaminants for which there is currently no regulation requiring monitoring or public reporting of their presence in our water supply or wastewaters. There are many emerging contaminants such as pesticides, pharmaceuticals, drugs, cosmetics, personal care products, surfactants, cleaning products, industrial for-mulations and chemicals, food additives, food packaging, metalloids, rare earth elements, nanomaterials, microplastics, and pathogens. The main sources of emerging contaminants are domestic discharges, hospital effluents, industrial wastewaters, runoff from agriculture, livestock and aquaculture, and landfill leachates. In particular, effluents from municipal wastewater treatment plants are major contributors to the presence of emerging contaminants in waters. Although many chemicals have been recently regulated as priority hazardous substances, conventional plants for wastewater and drinking water treat-ment were not designed to remove most emerging contaminants. Here, we review key examples of contamination in China, Portugal, Mexico, Colombia, and Brazil. Examples include persistent organic pollutants such as polychlorinated biphenyls, dibenzofurans, and polybrominated diphenyl ethers, in lake and ocean ecosystems in China; emerging contaminants such as alkylphenols, natural and synthetic estrogens, antibiotics, and antidepressants in Portuguese rivers; and pharmaceuticals, hormones, cosmetics, personal care products, and pesticides in Mexican, Brazilian, and Colombian waters. All continents are affected by these contaminants. Wastewater treatment plants should therefore be upgraded, e.g., by addition of tertiary treatment systems, to limit environmental pollution.

Currently, there is a great pollution of water by the dyes; due to this, several studies have been carried out to remove these compounds. However, the total elimination of these pollutants from the aquatic effluents has represented a great challenge for the scientific community, for which it is necessary to carry out investigations that allow the purification of water. In this work, we studied the bioadsorption of methylene blue on the surface of the biomass obtained from the algae D. antarctica. This material was characterized by SEM and FTIR. To the data obtained in the biosorption experiments, different models of biosorption and kinetics were applied, finding that the best fit to the obtained data is given by applying the pseudo-second-order models and the Toth model, respectively. It was also determined that the maximum adsorption capacity of MB on the surface of the biomass is 702.9 mg/g, which shows that this material has great properties as a bioadsorbent.

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The influence of particle size (0.3 and 5.0 mm) and heating rate (5, 10, and 20 °C min –1 ) on the kinetic parameters of pyrolysis of waste tire was studied by thermogravimetric analysis and mathematical modeling. Kinetic parameters were determined using the Friedman model, the Coats–Redfern model, and the ASTM E1641 standard based on Arrhenius linearization. In the Friedman model, the activation energy was between 40 and 117 kJ mol –1 for a particle size of 0.3 mm and between 23 and 119 kJ mol –1 for a particle size of 5.0 mm. In the Coats–Redfern model, the activation energy is in a range of 46 to 87 kJ mol –1 for a particle size of 0.3 mm and in a range of 43 to 124 kJ mol –1 for a particle size of 5.0 mm. Finally, in the ASTM E1641 standard, the activation energy calculated was between 56 and 60 kJ mol –1 for both particle sizes. This study was performed to obtain kinetic parameters from different mathematical methods, examining how the particle size and heating rate influence them.

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This work shows the results obtained to determine the noise in the baseline of a specially designed Tian Calvet-Type adsorption microcalorimeter. The results show that noise levels vary from 0.5 to 10 lV, which were evaluated varying the electrical work and the micro calorimeter surrounding temperature. Relationships can be seen between the variables employed in the observation of stability, temperature, potency levels and generated noise.