Performance, kinetic, and biodegradation pathway evaluation of anaerobic fixed film fixed bed reactor in removing phthalic acid esters from wastewater

Emerging and hazardous environmental pollutants like phthalic acid esters (PAEs) are one of the recent concerns worldwide. PAEs are considered to have diverse endocrine disrupting effects on human health. Industrial wastewater has been reported as an important environment with high concentrations of PAEs. In the present study, four short-chain PAEs including diallyl phthalate (DAP), diethyl phthalate (DEP), dimethyl phthalate (DMP), and phthalic acid (PA) were selected as a substrate for anaerobic fixed film fixed bed reactor (AnFFFBR). The process performances of AnFFFBR, and also its kinetic behavior, were evaluated to find the best eco-friendly phthalate from the biodegradability point of view. According to the results and kinetic coefficients, removing and mineralizing of DMP occurred at a higher rate than other phthalates. In optimum conditions 92.5, 84.41, and 80.39% of DMP, COD, and TOC were removed. DAP was found as the most bio-refractory phthalate. The second-order (Grau) model was selected as the best model for describing phthalates removal

Enhanced sono-photocatalysis of tetracycline antibiotic using TiO2 decorated on magnetic activated carbon (MAC@T) coupled with US and UV: A new hybrid system

A combined system including sonocatalysis and photocatalysis was applied for catalytic degradation of tetracycline (TC) antibiotic using TiO2 decorated on magnetic activated carbon (MAC@T) in coupling with ultraviolet (UV) and ultrasound (US) irradiations. MAC was fabricated via magnetization of AC using Fe3O4 nanoparticles. FESEM, EDS, TEM, BET, XRD, PL, VSM and UV�visible DRS techniques were used to characterize the catalyst features. The performance of MAC@T/UV/US system was examined under impact of different input variable such as catalyst loading, solution pH, initial TC concentration, US power, scavenging agents, chemical oxidants and co-exiting anions. The degradation rate was enhanced substantially when MAC@T coupled with US and UV irradiations. At optimal conditions, over 93 TC and 50 TOC were removed under 180 min reaction. Whereas, the complete removal of TC was obtained after 60 min treatment, when MAC@T/UV/US coupled with oxidants. Decreasing sequence of the inhibitory effect of anions was chloride > bicarbonate > phosphate > nitrate > sulfate. Both Fe leaching and loss of the decontamination were slight with reused times, indicating MAC@T has a high stability and reusability. According to trapping tests, holes, radOH and 1O2 were contributed in the degradation process. In conclusion, integration of MAC@T composite and US/UV for enhancing catalytic degradation efficiency can be introduced as a successful and promising technique, owing to excellent catalytic activity, easy recovery, good adsorption capacity and high durability and recycling potential. © 2019 Elsevier B.V

Co-implanting of TiO2 and liquid-phase-delaminated g-C3N4 on multi-functional graphene nanobridges for enhancing photocatalytic degradation of acetaminophen

Herein, an efficient all-solid-state Z-type photocatalyst, TiO2/graphene/g-C3N4 (TGCN), was fabricated, characterized and utilized toward acetaminophen (ACM) degradation under a simulated solar light (SSL). The acid-treatment-assisted exfoliation process was used to break Van-der-Waals bonds between the bulk g-C3N4 layers and yield of ultrathin g-C3N4 nanosheets was fully explained. Also, the importance of using HCl and water in the process was examined. Structural, morphological and surface features of samples were thoroughly determined using XRD, Raman, TGA, FTIR, EDX, DRS, TEM, HRTEM, FESEM, BET, PL, EIS and photocurrent analyses. By considering different locations of graphene nanosheets in the TGCN, different charge transfer mechanisms were purposed and investigated employing Coulomb's law and trapping experiments. Constructing the efficient Z-type photocatalyst by introduction of graphene as shuttle electron mediator to TiO2 and g-C3N4 nanocomposite significantly enhanced the degradation performance and photo-activity. The adsorption edge of the TGCN nanocomposite was extended to the visible·light region by g-C3N4 nanosheets benefiting a more favorable band gap position. The characterization results clarified that graphene facilitates photo-induced electron transportation and separation as well as improving the specific surface area and promoting the ACM adsorption capacity. Then, the most possible indirect Z-type charge separation mechanism for TGCN/SSL system was successfully confirmed by findings. Benefiting from the excellent synergetic effect of the catalyst individual systems, the ACM (50 mg/L) could reach up to complete degradation under SSL irradiation with the 0.6 g/L of TGCN (60:10:30) at pH = 9.0 within 120 min reaction. In the end, a tentative pathway for ACM decomposition was suggested. © 2021 Elsevier B.V

Exposure to atrazine by drinking water and the increased risk of neonatal complications in consequence: a meta-analysis

This meta-analysis evaluates the association between atrazine (ATR) exposure and small for gestational age (SGA), preterm birth (PTB), and low birth weight (LBW). A comprehensive search was done on academic databases (e.g. PubMed, Scopus, Embase, and Google Scholar) to achieve all pertinent studies up to May 2023. A pooled odd ratio (OR) and corresponding 95 confidence interval (CI) were applied to evaluate this correlation. As a result, five eligible studies met the inclusion criteria and were included in our study, and the result of the present meta-analysis showed that ATR exposure increased the risk of SGA (OR = 1.11; 95 CI = 1.03-1.20 for highest versus lowest category of ATR), PTB (OR = 1.16; 95 CI = 1.03-1.30), and LBW (OR = 1.26; 95 CI = 1.10-1.44). This meta-analysis suggests that ATR in drinking water may be a risk factor for SGA, PTB, and LBW