A high amount of nutrients can be found in urban wastewater (UW), which makes it difficult to treat. The purpose of this research was to evaluate the potential of the aquatic macrophytes Eichhornia crassipes, Pistia stratiotes, and Salvinia molesta in the treatment of UW. To evaluate the potential of each macrophyte, phytoremediation bioassays were established; the hydraulic retention time for each bioassay was 15 days. The physicochemical analysis of the water samples considered pH, turbidity, electrical conductivity (EC), total dissolved solids (TDS), dissolved oxygen (DO), chemical oxygen demand (COD), total carbon (TC), phosphates (PO₄³-P), nitrate (NO₃-N), and total nitrogen (TN). To evaluate the phytoremediation potential of each plant, the bioconcentration factors (BCFs) and translocation factors (TFs) for NO₃-N and PO₄³-P were evaluated. Likewise, the relative growth rates (RGRs) and total chlorophyll production of the macrophytes were measured. The results showed that the highest efficiency was achieved with the bioassays with E. crassipes, with removal values of 69.7%, 68.8%, 58.7%, 69.4%, 56.3%, and 40.9% for turbidity, COD, TOC, PO₄³-P, NO₃-N, and TN, respectively. The phytoremediation potential results showed that, for BCF, the highest value was 4.88 mg/g of PO₄³-P with E. crassipes, and for TF, it was 6.17 mg/g of PO₄³-P with S. molesta. The measurement of RGR and total chlorophyll for E. crassipes showed an increase of 0.00024 gg⁻¹d⁻¹ and an increase of 4.5%, respectively. On the other hand, the other macrophytes suffered decreases in chlorophyll content and RGR. Thus, E. crassipes is defined as the macrophyte with the greatest potential for the UW phytoremediation process.

A challenge for the oil refinement industry is the production of high-octane gasoline with a low benzene content. This work reports the calculation of the atmospheric benzene emissions generated from gasoline storage, transfer, and transport operations in Mexico, estimating 1.48 KBPD of environmental release. The aim was to estimate the minimum benzene emissions through operative improvements in refineries, initially by performing simulations of the Naphtha Catalytic Reforming (NCR) process using ASPEN HYSYS^® ver. 8.8 (34.0.08909) and then by optimizing the operative conditions to improve the reformate quality while reducing the benzene content. The operative ranges comprised hydrogen/hydrocarbon (H₂/HC) feedstock molar ratios from 2.0 to 6.0 and reaction temperatures from 450 to 525 °C, which were used as independent variables to assess the benzene content and the Research Octane Number (RON) of the produced gasoline. The Surface Response Method (SRM) and multi-objective optimization analysis were applied. The improved operative conditions were 491 °C and a H₂/HC ratio of 2.0, which allowed us to obtain a RON value of 89.87, an aromatics value of 37.39% (v/v), and a benzene value of 1.48% (v/v), with an estimated 16.44% drop in atmospheric benzene emissions, meaning a reduction in greenhouse gas emissions and climate change, thus favorably impacting public health by improving refinery operations. The simulation outcomes were compared with industrial-scale data and the experimental results, with significant similitudes being observed.

17β-estradiol (E2) is the natural estrogen with the most significant potential for endocrine disruption in the biota of aquatic ecosystems at trace concentrations. It is, therefore, essential to study treatments for water polluted with E2 that would guarantee its complete elimination and mineralization. Denitrification is a biological process shown to have the capacity to completely biodegrade drugs, such as ampicillin. This work is aimed to evaluate the biotransformation of 17β-estradiol by employing a denitrifying sludge. The assays performed were: (I) abiotic with 3.5 mg E2-C L⁻¹ and (II) denitrifying with 10 mg CH₃COO⁻-C L⁻¹ as the reference, 10 mg E2-C L⁻¹ as the sole electron donor, and a mixture of (mg L⁻¹) 10 E2-C with 10 CH₃COO⁻-C at C N⁻¹ of 1.1. The E2-C and NO₃⁻-N consumption efficiencies were greater than 99%, and HCO₃⁻-C and N₂ production yields were close to 1 in all assays. The denitrifying sludge could biodegrade up to 10 mg E2-C L⁻¹ as the sole electron donor and when mixed with 10 mg CH₃COO⁻-C L⁻¹. No intermediate metabolites were generated from the process.

Soils are the largest terrestrial carbon (C) reservoirs and play a key role in regulating the global C cycle and supporting essential ecosystem services. Soil C sequestration is a viable strategy to reduce atmospheric CO₂ concentrations and mitigate climate change. This study quantified soil C fractions and litter C stocks across five vegetation types in El Chico National Park, Hidalgo, Mexico (2015.55 ha): pine–oak, oyamel–oak, cedar, oyamel–Tlaxcal, and oyamel forests, all occurring under comparable climatic and edaphic conditions. Soil organic matter (SOM) was quantified as the organic fraction originating from decomposed plant and animal residues. No statistically significant differences (p > 0.05) were found among vegetation types for organic matter, total C, oxidizable C, or recalcitrant (non-oxidizable) C, indicating relative homogeneity across strata. Significant differences (p < 0.05) were detected in organo-mineral C (Cp) and poorly oxidizable C (Cdox), with oyamel–Tlaxcal and oyamel forests showing the highest values, respectively, suggesting enhanced potential for C stabilization and turnover. Oyamel forests stored 32.94% of total soil organic C and contributed disproportionately to park-wide C stocks given their dominance (85.6% of the total area). Leaf litter contained on average 6.60 Mg C ha⁻¹, representing 13,302.63 Mg C and 48,836.8 Mg CO₂ across the park. When integrated with soil C to 60 cm depth, total C and CO₂ stocks reached 643,474.26 Mg and 2,361,566.66 Mg, respectively. These findings highlight the critical role of oyamel forests as the main carbon sink in the park and reinforce the importance of conserving these ecosystems as a nature-based solution for climate change mitigation.

17β-estradiol (E2), ampicilina (AMP), así como los colorantes sintéticos Rojo 40 y Amarillo 5, se han incluido en el grupo de contaminantes emergentes (CEs). Estos generan diferentes problemas ambientales como disrupción endocrina en biota acuática a concentraciones traza. Debido a su compleja estructura son difíciles de degradar por tratamientos convencionales. Los procesos de oxidación avanzada (POA) tipo Fenton han mostrado resultados prometedores en la oxidación de compuestos orgánicos en tiempos cortos de reacción. En este trabajo se evaluó un proceso foto-Fenton con luz solar para la eliminación de E2, AMP, colorantes Rojo 40 y Amarillo 5 en agua con H2O2 como agente oxidante y FeSO4·7H2O como catalizador. Se obtuvieron eficiencias de oxidación de E2, AMP, Rojo 40 y Amarillo 5 superiores al 90 % y la degradación siguió un modelo de reacción de primer orden. Por ello, los procesos de oxidación foto-Fenton resultan eficientes en la oxidación de E2 y AMP, así como la decoloración de rojo 40 y amarillo 5.

Acetaminophen, more commonly known as paracetamol (APAP), is one of the most widely used analgesics and antipyretic drugs worldwide. Its presence in the environment poses a risk to the organisms it comes into contact with, which is why it has been classified as an emerging contaminant. Given its adverse effects and continuous discharge into water bodies, it is necessary to study efficient, environmentally sustainable processes for its complete removal. Denitrification is a biological process that has been studied for the biodegradation of recalcitrant compounds and certain pharmaceuticals such as 17β-estradiol and ampicillin, transforming them into harmless products such as N₂ and HCO₃⁻. In the present study, the biodegradation of 6 mg L⁻¹ of APAP-C was evaluated through a denitrifying process. Batch experiments were conducted, achieving acetaminophen (APAP) removal efficiencies (E_APAP-C) of 83.3 ± 0.86% and nitrate removal efficiencies (E_N-NO3⁻) of 100%. The substrates were predominantly converted into HCO₃⁻ and N₂, with yields greater than 0.9, while intermediates such as NO₂⁻ were observed only transiently during the reaction. At the end of the experimental period, no secondary metabolites were detected, indicating that intermediates did not accumulate to quantifiable levels.