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 cyclodextrin 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 oxidation processes as the most promising strategies because of their simplicity and efficiency.
Paracetamol adsorption in acidic, neutral and basic media on three activated carbons with different chemistry surfaces was studied. A granular activated carbon (GAC) was prepared from coconut shell; ...starting from this sample, an oxidized activated carbon (GACo) was obtained by treating the GAC with a boiling solution of 6 M nitric acid, so to generate a greater number of oxygenated surface groups. In addition, a reduced activated carbon (GACr) was obtained by heating the GAC at 1173 K, to remove the oxygenated surface groups. Paracetamol adsorption was higher for GACr due to the lower presence of oxygenated surface functional groups. Moreover, adsorption was highest at neutral pH. The magnitude of the interactions between paracetamol molecules and activated carbons was studied by measuring the immersion enthalpies of activated carbons in solution of paracetamol at different concentrations and pH values and by calculating the interaction enthalpy. The highest value was obtained for GACr in a paracetamol solution of 1000 mg L
at pH 7, confirming that paracetamol adsorption is favoured on basic activated carbons at pH values near to neutrality. Finally, the Gibbs energy changes confirmed the latter result, allowing explaining the different magnitudes of the interactions between paracetamol and activated carbons, as a function of solution pH.
Life expectancy (LE) and Health-adjusted life expectancy (HALE) are summary indicators that reflect a population's general life conditions and measure inequities in health outcomes. The objective of ...this study was to identify the differences in LE and HALE by sex, age group, and state in Mexico from 1990 to 2019. Also, to evaluate whether the changes in HALE are related to sociodemographic indicators and indicators of access to and quality of health services. A secondary analysis was performed based on the Global Burden of Disease, Injuries, and Risk Factors Study (GBD). Data were obtained for LE (by sex and state) and HALE (by sex, age group, and state) for the years 1990, 2010, and 2019. The correlations between HALE with the Socio-Demographic Index (SDI) and with the Healthcare Access and Quality (HAQ) Index were estimated for 1990 and 2019 (by total population and sex). LE and HALE had an absolute increase of 6.7% and 6.4% from 1990 to 2019, mainly among women, although they spent more years in poor health (11.8 years) than men. The patterns of LE and HALE were heterogeneous and divergent by state. In 2019, the difference in HALE (for both sex) between the states with the highest (Hidalgo) and the lowest (Chiapas) value was 4.6 years. Progress in LE and HALE has slowed in recent years; HALE has even had setbacks in some states. Gaps between men and women, as well as between states, are persistent. Public and population policymaking should seek to lengthen LE and focus on ensuring that such years are spent in good health and with good quality of life.
Objectives
To determine the prevalence of self‐reported abuse in elderly Mexican adults with long‐term disabilities and to identify associated risk factors.
Design
Secondary analysis of the ...Perception of Disability in Mexican Population 2010 survey.
Setting
Mexico.
Participants
Individuals aged 60 and older with long‐term disabilities without cognitive decline (N = 1,089).
Measurements
The elder abuse variable was constructed from the 21 questions included in the survey that assessed the presence of physical, psychological, sexual, and financial exploitation. Independent variables included demographic characteristics, self‐rated health, disability (number of functional domains or basic activities), multimorbidity, emotional symptoms, health resources used, and informal help.
Results
The prevalence of elder abuse was 32.1%. The most frequent type of abuse was psychological (28.1%). Nearly 58% of respondents reported one type of abuse, 34% reported two types, and 8% reported more than three types. The most common combination of two types of abuse was psychological with financial exploitation. Variables associated with the presence of psychological, physical, and sexual abuse (conflict abuse) were age 80 and older, 9 or more years of education, unemployment, negative self‐rated health, three or more disabilities, emotional symptoms, and history of hospitalization. Financial exploitation was associated with age 80 and older, being married or living with a partner, 9 or more years of education, unemployment, living in an urban area, negative self‐rated health, three or more disabilities, emotional symptoms, and history of hospitalization.
Conclusion
The prevalence of abuse in elderly Mexican adults with long‐term disabilities is high. Associated factors were level of education, number of disabilities, and health status. Further studies should explore the applicability of these results to other populations.
In this research, a calorimetric evaluation of activated carbon-type adsorbent solids prepared by chemical activation of African palm shells with solutions of Fe(NO
3
)
3
and Cu (NO
3
)
2
salts with ...change in concentration was carried out. In the investigation, the immersion calorimetry in porous carbon-type solids in water, dichloromethane, and benzene was determined. The solids were characterized by the nitrogen adsorption technique at 77 K and the determination of functional groups by Boehm titrations. The calorimetric evaluation showed that the immersion of porous materials generated immersion enthalpy values between −10.8 and −131 J g
−1
. The immersion calorimetry of these materials in the immersion liquids varied with respect to the change of chemical agents and to the change of concentrations at which these materials were prepared, showing variations in textural and chemical characteristics of porous solids. The BET areas obtained are between 120 and 1360 m
2
g
−1
, and pore volumes are between 0.05 and 0.51 cm
3
g
−1
; these parameters increased proportionally to the increase in the values of immersion enthalpies. The adsorbent solids obtained are used in the adsorption of CO
2
, in this investigation, the calorimetric study was carried out in solvents with different polarities, in order to correlate these enthalpic properties of the activated carbons with the surface area and the adsorption, which presented values between 88 and 218 mg g
−1
.
Activated carbons from shell eucalyptus (Eucalyptus globulus) were prepared by chemical activation through impregnation with solutions of two activators: sulfuric acid and sodium hydroxide, the ...surface areas for activated carbons with base were 780 and 670 m2 g−1 and the solids activated with acid were 150 and 80 m2 g−1. These were applying in adsorption of priority pollutants: phenol, 4-nitrophenol, and 4-chlorophenol from aqueous solution. Activated carbon with the highest adsorption capacity has values of 2.12, 2.57, and 3.89 on phenol, 4-nitrophenol, and 4-chlorophenol, respectively, and was activated with base. In general, all carbons adsorption capacity was given in the following order: 4-chlorophenol > 4-nitrophenol > phenol. Adsorption isotherms of phenols on activated carbons were fitted to the Langmuir, Freundlich, and Dubinin-Radusckevisch-Kanager models, finding great association between them and experimental data. A thermodynamic study was performed, the exothermic nature and spontaneous nature of the adsorption process were confirmed, and the favorability of adsorption on activated carbons with NaOH was confirmed by energy relations and concluded that the adsorption process of phenolic compounds from the activated carbon obtained is physical. The pH of solutions and pH at point of zero charge of the solid play an important role in the adsorption process.
The adsorption of salicylic acid, acetaminophen, and methylparaben (pharmaceutical products derived from phenol) on carbons activated with different surface chemistries was carried out. We evaluated ...the effect of the physicochemical properties of the adsorbent and adsorbates on the adsorption capacity. A study of the adsorbate–adsorbent interactions via immersion calorimetry in the analytes solutions at different concentrations was included, in addition to the equilibrium data analysis. The results show that the pharmaceutical compounds (2.28–0.71 mmol g−1) have lower adsorption capacities in the activated carbon with the highest content of oxygenated groups (acids), while the activated carbons with amphoteric characteristics increase the capacities of adsorption (2.60–1.38 mmol g−1). This behavior may be associated with the increased affinity between the adsorbent and solvent due to the presence of polar groups, which was corroborated by the high immersion enthalpy value in water (ΔHimmH2O = −66.6 J g−1). The equilibrium data, adjusted to the Freundlich adsorption model, indicated that the heterogeneous adsorption processes involve immersion enthalpy values between −9.42 and −24.3 J g−1.
In this study, the mechanisms of methylparaben adsorption onto activated carbon (AC) are elucidated starting from equilibrium and thermodynamic data. Adsorption tests are carried out on three ACs ...with different surface chemistry, in different pH and ionic strength aqueous solutions. Experimental results show that the methylparaben adsorption capacity is slightly affected by pH changes, while it is significantly reduced in the presence of high ionic strength. In particular, methylparaben adsorption is directly dependent on the micropore volume of the ACs and the π- stacking interactions, the latter representing the main interaction mechanism of methylparaben adsorption from liquid phase. The equilibrium adsorption data are complemented with novel calorimetric data that allow calculation of the enthalpy change associated with the interactions between solvent-adsorbent, adsorbent-adsorbate and the contribution of the ester functional group (in the methylparaben structure) to the adsorbate⁻adsorbent interactions, in different pH and ionic strength conditions. It was determined that the interaction enthalpy of methylparaben-AC in water increases (absolute value) slightly with the basicity of the activated carbons, due to the formation of interactions with π- electrons and basic functional groups of ACs. The contribution of the ester group to the adsorbate-adsorbent interactions occurs only in the presence of phenol groups on AC by the formation of Brønsted⁻Lowry acid⁻base interactions.
Caffeine and diclofenac are molecules with high human intake, and both belong to the 'emergent' class of contaminants. These compounds have been found at different concentrations in many sources of ...water worldwide and have several negative impacts on aquatic life systems; that is why the search for new alternatives for their removal from aqueous media is of transcendental importance. In this sense, adsorption processes are an option to attack this problem and for this reason, biochar could be a good alternative. In this regard, were prepared six different biochar from fique bagasse (FB), a useless agroindustry by-product from fique processing. The six biochar preparations were characterized through several physicochemical procedures, while for the adsorption processes, pH, adsorption time and concentration of caffeine and diclofenac were evaluated. Results showed that the biochar obtained by pyrolysis at 850 °C and residence time of 3 h, labeled as FB850-3, was the material with the highest adsorbent capacity with values of 40.2 mg g
and 5.40 mg g
for caffeine and diclofenac, respectively. It was also shown that the experimental data from FB850-3 fitted very well the Redlich-Peterson isotherm model and followed a pseudo-first and pseudo-second-order kinetic for caffeine and diclofenac, respectively.
Activated carbons were prepared from a lignocellulosic material, African palm shells (Elaeis guineensis), by chemical impregnation of the precursor with solutions of 1–7% w/v Cu(NO3)2 at five ...different concentrations. These were carbonized in a carbon dioxide atmosphere at 1073 K to obtain different carbons. Their textural properties were characterized by nitrogen and carbon dioxide adsorption isotherms in order to evaluate the pore-size distribution. The immersion enthalpies of the activated carbons in benzene, dichloromethane, and water were determined. The CO2 adsorption capacities of the materials at 273 K under low-pressure conditions were also determined. Chemical characterization was performed by mass spectrometry, Fourier transform infrared spectroscopy, and temperature-programmed reduction. With this method of preparation under the concentrations described, activated micro–mesoporous carbons were obtained, with the formation of highly mesoporous solids that favored the process of diffusion of molecules of CO2 into the material. Here, we show that activated carbons were obtained with different textural characteristics: surface Brunauer–Emmett–Teller areas varied between 473 and 1361 m2 g–1 and micropore volume between 0.18 and 0.51 cm3 g–1. The activated carbon with the highest values of textural parameters was ACCu5-1073. Micro–mesoporous solids were obtained with the methodology used. This is important as it may help the entry of CO2 molecules into the pores. The adsorption of CO2 in the materials prepared presented values between 103 and 217 mg CO2 g–1; the values of volume of narrow microporosity obtained were between 0.16 and 0.45 cm3 g–1. The solid with the greatest capacity for adsorption of CO2 and volume of narrow microporosity was ACCu3-1073. The use of these solids is of importance for future practical and industrial applications. The adsorption kinetic of CO2 in the activated carbons prepared with metallic salt of copper is in good accordance with the intraparticle diffusion model, for which diffusion is the rate-limiting step. The adsorption of CO2 in the prepared activated carbons is favorable from the energy and kinetic point of view, as these accompanied by the presence of wide micro–mesoporosity favor the entry of CO2 into the micropores.
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