Research progress on the generation of NDMA by typical PPCPs in disinfection treatment of water environment in China: A review.

The drugs and personal care products in water sources are potential threats to the ecological environment and drinking water quality. In recent years, the presence of PPCPs has been detected in multiple drinking water sources in China. PPCPs are usually stable and resistant to degradation in aquatic environments. During chlorination, chloramination, and ozonation disinfection processes, PPCPs can act as precursor substances to generate N-nitrosodimethylamine (NDMA) which is the most widely detected nitrosamine byproduct in drinking water. This review provides a comprehensive overview of the impact of PPCPs in China's water environment on the generation of NDMA during disinfection processes to better understand the correlation between PPCPs and NDMA generation. Chloramine is the most likely to form NDMA with different disinfection methods, so chloramine disinfection may be the main pathway for NDMA generation. Activated carbon adsorption and UV photolysis are widely used in the removal of NDMA and its precursor PPCPs, and biological treatment is found to be a low-cost and high removal rate method for controlling the generation of NDMA. However, there are still certain regional limitations in the investigation and research on PPCPs, and other nitrosamine by-products such as NMEA, NDEA and NDBA should also be studied to investigate the formation mechanism and removal methods.

Hydrodynamic behavior and start-up performance of a periodic anaerobic baffled reactor in an "every second" switching manner treating traditional Chinese medicine wastewater.

Most studies focus on the "clockwise sequential" switching manner for a four-compartment periodic anaerobic baffled reactor (PABR), while the exploration of the "every second" option on the feasibility for real industrial wastewater treatment is rarely reported. Hence, a PABR-treating traditional Chinese medicine wastewater was run continuously in "every second" switching manner with both switching period T and hydraulic residence time of 48 h. Satisfactory start-up performance was achieved during the operation of a climbing average organic load rate at approximately 1, 2, 4, and 6 kg chemical oxygen demand (COD) m-3 d-1 for 12, 24, 24, and 6 days, respectively. The average COD removal was 87.20% after the second lifting of OLR and 89.98% after the third one. Denaturing gradient gel electrophoresis and its cluster analysis showed that the microbial communities in each compartment adapted their structure in response to the periodically changing micro-ecology conditions. Moreover, the residence time distribution test with tap water in the clean PABR was carried out in experiments and computational fluid dynamics (CFD) simulation, both of which were in good agreement. The CFD model output visualized the flow velocity field and hydrodynamic-mass transport inside the PABR. Optimization of operation pattern in PABR including switching manner and frequency depended on both the type of waste being treated and the flexibility of biomass to periodically changing micro-ecology conditions.

Catalytic activity of H2O2 by goethite and lepidocrocite: Insight from 5-bromosalicylic acid removal mechanism and density functional theory calculation (ID:CHEM114760).

We have compared the elimination of 5-bromosalicylic acid (BSA) in the systems of goethite (α-FeOOH)/H2O2 and lepidocrocite (γ-FeOOH)/H2O2. The results demonstrated that BSA (10 mg L-1) could be successfully adsorbed on α- and γ-FeOOH (0.5 g L-1) and then effectively degraded after the addition of H2O2 (14.7 mM). BSA adsorption on both α- and γ-FeOOH followed pseudo-second order adsorption kinetic models, with γ-FeOOH having greater adsorption ability than α-FeOOH. In the α-FeOOH/H2O2 system, BSA degradation was well fitted with the pseudo-second order kinetics, whereas the oxidation in γ-FeOOH/H2O2 system had a two-stage pseudo-first order kinetics. Electron paramagnetic resonance (EPR) results for these two systems revealed the presence of •OH and •OOH, and further tests with radical captures demonstrated their dominance in degrading BSA. Based on the electronic structure analysis, electrons were more easily transferred from the H2O2 molecule to the Fe atoms of α-FeOOH, explaining the density functional theory (DFT) calculation results, which showed that α-FeOOH performed better in catalyzing the decomposition of H2O2. However, the free radicals are more likely to desorb from γ-FeOOH, which made the γ-FeOOH/H2O2 system more efficient in degrading BSA.

Activation of the combined hydrogen peroxide and peroxymonosulphate by lepidocrocite for chloramphenicol removal: kinetics and mechanisms.

The main compositions of pipe deposits from water distribution networks are potential iron resources, which can be used as catalysts to activate the combined hydrogen peroxide (HP) and peroxymonosulphate (PMS) system to produce reactive oxidative species (ROSs) to degrade pollutants. As a result, the degradation efficiency of chloramphenicol (CAP) in the HP/PMS dual-oxidant system could reach as high as 75.21% within 100 min with hydroxylamine (HA) assistance, and the dual-oxidant method had a wide pH applied range. To explore the mechanism of the dual-oxidant system in detail, several main affecting factors were investigated. In addition, the hydroxyl radical(•OH) was identified as the predominant radicals by Electron paramagnetic resonance (EPR) and the Radical scavenger test (RST). According to the competition kinetics experiment, the reaction rate of CAP with •OH was 1.933(± 0.052) × 1010 M-1s-1 in the HP/PMS dual-oxidant system, which was higher than the HP single oxidant system (6.10(± 0.036) × 109 M-1s-1). And the role of HA was explored , including reduction and competition. Six degradation products were detected by the liquid chromatography-mass spectrometry (LC-MS) and their toxicity was analyzed by the ecological structure-activity relationship (ECOSAR) predictive model. These findings further provide a theoretical basis for the practical application of pipe deposits and advance the development of in-situ removal of pollutants in water distribution networks in the future promisingly.

Tailoring S-vacancy concentration changes the type of the defect and photocatalytic activity in ZFS.

Defect engineering is crucial in the development of semiconductor catalyst activity. However, the influence of defect/vacancy density and states on catalysis remains vague. Thus, the optimized sulfur vacancy (SV) state is achieved among Fe-ZnS models (ZFS) via a chemical etching strategy for photocatalytic degradation (PD). As the SV concentration (ρSV) increases, the predominant state of vacancies changes from isolated defects－a state to a combination of a state and vacancy clusters－e state, as verified by positron annihilation and X-ray absorption fine structure spectra. However, the two types of defect states activated the intrinsic activity of the crystal via radically different mechanisms and exerted different degrees of influence on PD activity, as revealed by first-principles calculations and quantitative structure-activity relationship. Our results suggest that the SV activity is strongly influenced by its concentration in the ZFS crystal, while the vacancy concentration is not a control parameter for the PD activity, but a defect form. The underlying essence of atomic defects behavior affecting crystal catalytic activity at the atomic level is also revealed in this paper. Uncovering these structural relationships provide a theoretical basis for designing effective catalysts.

Simultaneous removal of NOX and SO2 from flue gas in an integrated FGD-CABR system by sulfur cycling-mediated Fe(II)EDTA regeneration.

Chemical absorption-biological reduction (CABR) process is an attractive method for NOX removal and Fe(II)EDTA regeneration is important to sustain high NOX removal. In this study a sustainable and eco-friendly sulfur cycling-mediated Fe(II)EDTA regeneration method was incorporated in the integrated biological flue gas desulfurization (FGD)-CABR system. Here, we investigated the NOX and SO2 removal efficiency of the system under three different flue gas flows (100 mL/min, 500 mL/min, and 1000 mL/min) and evaluated the feasibility of chemical Fe(III)EDTA reduction by sulfide in series of batch tests. Our results showed that complete SO2 removal was achieved at all the tested scenarios with sulfide, thiosulfate and S0 accumulation in the solution. Meanwhile, the total removal efficiency of NOX achieved ∼100% in the system, of which 3.2%-23.3% was removed in spray scrubber and 76.7%-96.5% in EGSB reactor along with no N2O emission. The optimal pH and S2-/Fe(III)EDTA for Fe(II)EDTA regeneration and S0 recovery was 8.0 and 1:2. The microbial community analysis results showed that the cooperation of heterotrophic denitrifier (Saprospiraceae_uncultured and Dechloromonas) and iron-reducing bacteria (Klebsiella and Petrimonas) in EGSB reactor and sulfide-oxidizing, nitrate-reducing bacteria (Azoarcus and Pseudarcobacter) in spray scrubber contributed to the efficient removal of NOX in flue gas.

Fate of household and personal care chemicals in typical urban wastewater treatment plants indicate different seasonal patterns and removal mechanisms.

Studies on the presence and fate of household and personal care chemicals (HPCCs) in wastewater treatment plants (WWTPs) are important due to their increasing consumption worldwide. The seasonal patterns and removal mechanisms of HPCCs are not well understood for WWTPs that apply different treatment technologies. To answer these questions, the sewage and sludge samples were taken from 10 typical WWTPs in Northeast China. Levels of UV filters in the influents in the warm season were significantly greater than that of the cold season (p < 0.05). Significant seasonal differences were found for the removals of many HPCCs. Results revealed that the highest removal efficiencies were found for linear alkylbenzene sulphonates with values ranging from 97.2% to 99.7%, and the values were 50.0%-99.9% for other HPCCs. The SimpleTreat model demonstrated that the studied WWTPs were operating with high efficiency at the time of sampling. The sorption of HPCCs to sludge can be strongly associated with their physicochemical parameters. Mass balance calculation suggested that sorption was the dominant mechanism for the removal of antimicrobials, while degradation and/or biotransformation were the other mechanisms for removing the most HPCCs in the WWTPs. This study real the factors influencing the seasonal patterns and removal mechanisms which imply the need for further studies to fully understands the plant and human health implications as sludge could be used in the municipal land application of biosolids.

Activating the Basal Plane of 2H-MoS2 by Doping Phosphor for Enhancement in the Photocatalytic Degradation of Organic Contaminants.

The 2H phases of MoS2 (2H-MoS2) monolayers present a wealth of new opportunities in photocatalysis owing to their photoinduced catalyzing ability and excellent charge carrier mobility. However, the complete release of their catalytic activities is restricted by their inert basal planes. Although the inert base planes of 2H-MoS2 are known to be activated by atomic doping, the operational principle of the exotic atoms remains vague. In this study, the unutilized inert base sites of MoS2 were activated via an oxygen-aided P-substituted method (denoted as POMS). Molecular structural tests and analyses of POMS indicated that the inert MoS2 substrate is activated when the inerratic crystal phases transform to amorphous phases in the P-doping process. The fully activated inert base planes provide sufficient reaction sites for photo-oxidized water contaminants. The designed POMS presented superior activity in organic degradation and completely removed sulfamethoxazole within 20 min. Uncovering these operational principles provides a theoretical basis for designing effective catalysts.

Adsorption and catalytic performance of pipe growth rings from water distribution networks using 5-BSA as the target pollutant.

In this study, we investigated the use of pipe growth rings from water distribution networks as a catalyst in heterogeneous Fenton-like oxidation processes. The major constituents of real pipe growth rings (α- and γ-FeOOH) were prepared and considered as a simulated growth ring (SGR). Its performance in removing 5-bromosalicylic acid (5-BSA), a novel phenolic halogenated disinfection byproduct, was examined. SGR exhibited strong catalytic ability and a certain degree of adsorption capacity. Under acidic conditions, the adsorption and oxidation efficiencies were 32.65% and 87.67%, respectively. Furthermore, 72.19% of 5-BSA could be oxidized even at pH0 of 7. Kinetic characterizations at various temperatures revealed that both the adsorption and catalytic oxidation processes followed pseudo-second-order kinetic models and were surface-controlled with high activation energies (31.26 and 23.58 kJ mol-1, respectively). Ecotoxicity analyses of the transformation products (TPs) showed that the SGR/H2O2 system could effectively reduce the toxicity of 5-BSA. Moreover, the number of iron ions leaching from SGR was below 0.1 mg L-1 in all experiments. The results of this study support further investigation of using real pipe growth rings in off-line water treatment, as well water network contamination remediation.

Assessing the distributions and fate of household and personal care chemicals (HPCCs) in the Songhua Catchment, Northeast China.

Many household and personal care chemicals (HPCCs) are of environmental concern due to their potential toxicity to humans and wildlife. However, few studies investigate the spatiotemporal variations and fate of HPCCs in large-scale river systems. Here, river water and sediment samples from the Songhua River in Northeast China were analyzed for seven classes of HPCCs. Correlation analysis suggested similar sources and environmental behavior for compounds from the same HPCC classes. In the river water, the concentrations of most HPCCs in the cold season were significantly higher than that of the warm season (p < 0.01). Significantly higher levels of target compounds were found in the downstream water samples of a city, suggesting the influence of human activities on the distributions of HPCCs. The concentrations and distributions of most HPCCs were controlled by primary emission sources. The derived dissolved concentrations of HPCCs suggested that small amounts of caffeine and parabens were partitioned onto particles, while large amounts of many other HPCCs were bound to the particle phase. Water-sediment distribution coefficients (log Kd) ranged from 1.59 for caffeine to 3.95 for benzalkonium chloride-C14. This work presents new insights into the environmental behavior of HPCCs and the factors affecting their fate in river systems.

A tubular electrode assembly reactor for enhanced electrochemical wastewater treatment with a Magnéli-phase titanium suboxide (M-TiSO) anode and in situ utilization.

The electrochemical oxidation technology has been widely used for the waste water treatment and water reuse because of its easy-to-operate nature, an effective removal of pollutants and non-secondary pollution. However, the price of electrode materials, the limitation of mass transfer and the associated effects on contaminant degradation hamper its application. Within this context, an in situ utilization tubular electrode assembly reactor (TEAR) was proposed, in which a stainless steel pipe (SSP) was used as the cathode, and a tubular Magnéli-phase titanium suboxide (M-TiSO) anode was posited in the center of that pipe. Besides the cathode and anode, an integral electrochemical system to treat water pollutants was constituted with a spiral static mixer made from three-dimensional (3D) printing. A spiral static mixer was pushed into the interspace of electrodes to minimize the adverse effect caused by inhomogeneous distribution of pollutants. Here, the effects of current density and resident time on the removal of methylene blue (MB) and total organic carbon (TOC) were investigated, the corresponding hydrodynamics was studied using computational fluid dynamics (CFD), and the long-term stability of removing MB by the reactor was discussed. The results indicated that the MB and TOC removal rate was enhanced at specific current density with a static mixer and the velocity distribution tended to be more homogeneous. Moreover, the anode surface shear force and heat transfer were increased by improving the fluid state. This study proposed an in situ utilization concept and provided a potential value for feasible and efficient water treatment.

Effects of bacterial community composition and structure in drinking water distribution systems on biofilm formation and chlorine resistance.

Community-intrinsic properties affect the composition and function of a microbial community. Understanding the microbial community-intrinsic properties in drinking water distribution systems (DWDS) could help to select disinfection strategies and aid in the prevention of waterborne infectious diseases. In this study, we investigated the formation of multi-species biofilms in six groups, each consisting of four or five mixed bacterial strains isolated from a simulated DWDS, at different incubation times (24, 48, and 72 h). We then evaluated the chlorine resistance of the 72-h multi-species biofilms in the presence of 0.3, 0.6, 1, 2, 4, and 10 mg/L residual chlorine. Microbacterium laevaniformans inhibited the formation of multi-species biofilms, Sphingomonas sp., Acinetobacter sp. and A. deluvii had the effect of promoting their growth, and B. cereus has little effect on the growth of multi-species biofilms. However, these inhibition and promotion effects were weak and inadequate to completely control the growth of multi-species biofilms. All multi-species produced strong biofilms after 72 h incubation, which could be due to microbial community-intrinsic properties. Community-intrinsic properties could maintain high EPS production and cell-to-cell connections in multi-species biofilms, and could affect the formation of multi-species biofilms. The chlorine resistance of multi-species biofilms was significantly improved by B. cereus, but significantly reduced by M. laevaniformans. These results indicated that the microbial community-intrinsic properties were influenced by the environment. At a relatively low disinfectant concentration (<2 mg/L residual chlorine), the community-intrinsic properties were maintained; however, when the disinfectant concentration was increased to 2-4 mg/L residual chlorine, the community-intrinsic properties weakened, and significantly affected the resistance of the microbial communities to the disinfectant. With further increases in concentration, to >4 mg/L residual chlorine, no significant difference was observed in the disinfectant resistance of the microbial community.

Significant acceleration of Fe2+/ peroxydisulfate oxidation towards sulfisoxazole by addition of MoS2.

Activation of peroxydisulfate (PDS) by Fe2+ has been considered as an effective activation method to generate reactive oxygen species (ROS). However, the process is limited for the low production yield of ROS owing to the inefficient Fe3+/Fe2+ cycle. Herein, we demonstrated that Fe2+/PDS system in the presence of molybdenum sulfide (MoS2) was significantly efficient for the degradation of sulfisoxazole (SIX). As a co-catalyst in the Fe2+/PDS system, MoS2 could greatly enhance the Fe3+/Fe2+ cycle by the exposed Mo4+ active sites, which could also improve the PDS decomposition efficiency. As a result, the degradation efficiency of SIX in the MoS2/Fe2+/PDS system could reach to as high as 97.1% within 40 min, which was in distinct comparison with the 45.5% achieved by Fe2+/PDS system without MoS2. Besides, effects of various reaction conditions on SIX degradation were also evaluated during the experiments, including the dosages of MoS2, Fe2+, PDS and initial solution pH and the coexisting inorganic anions. In addition, both of sulfate radicals and hydroxyl radicals were identified as the dominant active species for SIX degradation by the radical scavenging experiments and verified by electron paramagnetic resonance (EPR). This study provides a promising idea for the degradation of organic contaminants in water treatment based on Fe2+/PDS process.

Modification of graphite felt doped with nitrogen and boron for enhanced removal of dimethyl phthalate in peroxi-coagulation system and mechanisms.

To enhance the generation of hydrogen peroxide (H2O2), a modified graphite felt cathode doped with nitrogen and boron was developed and used in peroxi-coagulation system to degrade dimethyl phthalate (DMP). After a simple modification method, the yield of H2O2 on cathode increased from 9.39 to 152.8 mg/L, with current efficiency increased from 1.61 to 70.3%. Complete degradation of DMP and 80% removal of TOC were achieved within 2 h at the optimal condition with pH of 5, cathodic potential of - 0.69 V (vs. SCE), oxygen aeration, and electrode gap of 1 cm. Possible mechanism with synergistic effect of electro-Fenton and electrocoagulation process in the peroxi-coagulation system was revealed via quenching experiments. The prospect of this system in the effluent of landfill leachate and domestic sewage was studied, achieving 50% and 61% of DMP removal in 2 h. This efficient system with simple modified cathode had promising prospects in practical applications.

Analysis of Environmental Activities for Developing Public Health Investments and Policies: A Comparative Study with Structure Equation and Interval Type 2 Fuzzy Hybrid Models.

The design of elements which exert pivotal effects on leisurely physical activity (LPA) in open space is an important part of urban development. However, little research has been done about the influence and discrepancies of those elements in different types of open space. To research these issues and to guide the design of urban open space, a survey from 8 open spaces (2 curtilage, 2 neighborhood squares (NS), 2 parks, and 2 campus) is conducted and a questionnaire is administered. Simultaneous analysis of several groups (SASG) of Structure equation model (SEM) is used, and the effects and discrepancies are acquired. In addition to this situation, interval type 2 (IT2) fuzzy hybrid decision making model is proposed in the second analysis. In this framework, IT2 fuzzy decision-making trial, evaluation laboratory (DEMATEL), and IT2 fuzzy technique for order preference by similarity to ideal solution (TOPSIS) methods are used. The results show that the influence relationships between elements and LPA did exist in four groups. Another important conclusion is that there were discrepancies of influence among different space groups. Physical environment (PE) has the greatest influence on LPA in the curtilage, whereas facilities exert the most effect in NS group. Additionally, amenities only have significant impact in parks and facilities only exercise remarkable influence on duration on campus. In addition to them, it is also identified that key design elements are presented for different types of space and that design strategy is provided through 4 specific examples.

Degradation of chloramphenicol by α-FeOOH-activated two different double-oxidant systems with hydroxylamine assistance.

The pipe deposits from water distribution network are iron-wastes, which could be used as a catalyst of advanced oxidation processes (AOPs). This paper prepared one main composition (α-FeOOH) of pipe deposits and compared the difference of chloramphenicol (CAP) degradation by α-FeOOH-activated hydrogen peroxide/persulfate and α-FeOOH-activated hydrogen peroxide/peroxymonosulfate with hydroxylamine assistance. Several key affecting factors were investigated. The results revealed that the double-oxidant system has a synergy effect in CAP degradation process. The hydroxyl radicals were identified as the predominant radicals in two different degradation processes via electron paramagnetic resonance (EPR) technique. The possible degradation pathways and products were confirmed by liquid chromatography-mass spectrometry (LC-MS). This study provided a theoretic research for pollutant removal by taking full advantage of pipe deposits and advance the development of water quality security in water distribution network in future.

Bioelectrochemical system for the enhancement of methane production by anaerobic digestion of alkaline pretreated sludge.

An increasing interest is devoted to combined microbial electrolysis cell-anaerobic digestion (MEC-AD) system which could convert waste activated sludge into biogas. In this study series tests were initially conducted to study the effect of alkaline pretreatment on AD system and the results showed that alkaline pretreatment could promote the dissolution of organic matters in the sludge and thus improve the methane production. Then, the methane production in combined MEC-AD system fed with alkaline-pretreated sludge was investigated. The results indicated that the methane productions increased by 37% and 42% when applied voltage was 0.5 V and 0.8 V. The microbial electrochemical system strongly promoted the growth of Euryarchaeota (Methanosaeta and Methanobacterium). Meanwhile, the abundance of Paraclostridium increased from 17.9% to 38.5% when applied voltage was 0.8 V, suggesting an enhanced fermentation and acetogenesis process. The results of energy balance estimation indicated that MEC-AD system at 0.5 V could achieve higher net energy output.

Startup and stable operation of advanced continuous flow reactor and the changes of microbial communities in aerobic granular sludge.

In this study, the granular sludge was operated under low aeration condition in sequencing batch reactor (SBR) and advanced continuous flow reactor (ACFR), respectively. Through increasing the sludge retention time (SRT) from 22 days to 33 days, the ACFR was successful startup in 30 days and achieved long term stable operation. Under SBR operation condition, the aerobic granular sludge (AGS) showed good nitrogen (60%), phosphorus (96%) and COD removal performance. During stable operation of continuous-flow, the nitrogen removal efficiency was increasing to 70%, however, the phosphorus removal efficiency could only be restored to 65%. Meanwhile, the sludge discharge volume from ACFR was about half of that in SBR. Results of high-throughput pyrosequencing illustrated that methanogenic archaea (MA), ammonia oxidizing archaea (AOA), denitrifying bacteria (DNB), denitrifying polyphosphate-accumulating organisms (DPAOs) played an important role in the removal of nutrients in ACFR. This study could have positive effect on the practical application of AGS continuous flow process for simultaneous biological nutrient removal (SBNR).

Biofilm formation potential and chlorine resistance of typical bacteria isolated from drinking water distribution systems.

Biofilms are the main carrier of microbial communities throughout drinking water distribution systems (DWDSs), and strongly affect the safety of drinking water. Understanding biofilm formation potential and chlorine resistance is necessary for exploring future disinfection strategies and preventing water-borne diseases. This study investigated biofilm formation of five bacterial strains isolated from a simulated DWDS at different incubation times (24 h, 48 h, and 72 h), then evaluated chlorine resistance of 72 h incubated biofilms under chlorine concentrations of 0.3, 0.6, 1, 2, 4, and 10 mg L-1. All five bacterial strains had biofilm formation potential when incubated for 72 h. The biofilm formation potential of Acinetobacter sp. was stronger than that of Bacillus cereus, Microbacterium sp. and Sphingomonas sp. were moderate, and that of Acidovorax sp. was weak. In contrast, the order of chlorine resistance was Bacillus sp. > Sphingomonas sp. > Microbacterium sp. > Acidovorax sp. > Acinetobacter sp. Thus, the chlorine resistance of a single-species biofilm has little relation with the biofilm formation potential. The biofilm biomass is not a major factor affecting chlorine resistance. Moreover, the chlorine resistance of a single-species biofilm is highly related to the physiological state of bacterial cells, such as their ability to form spores or secrete extracellular polymeric substances, which could reduce the sensitivity of the single-species biofilm to a disinfectant or otherwise protect the biofilm.

Adsorption process of tetrachloroethylene (PCE) on network growth ring.

This study was undergone to investigate the adsorption characteristics of tetrachloroethylene (PCE) on water supply network growth ring. According to the chemical composition of real network growth ring, iron oxide mixture containing synthesized goethite and lepidocrocite was applied as simulated growth ring. The results demonstrate that competition could take place only between PCE and the co-present organic non-ionic compound, while inorganic salt had no discernible effect on PCE adsorption. A maximum adsorption capacity of 33.118 mg g-1 at equilibrium was achieved. By the non-linear regression method, the equilibrium adsorption data fitted well with the Freundlich isotherm model (R2 = 0.994), and the kinetic data obeyed pseudo-first order model (R2 = 0.985). Thermodynamic tests indicate the spontaneous and exothermic nature of adsorption process. In addition, no significant variation between the FTIR spectra of the iron oxide mixture before and after adsorption was observed, which verifies that hydrogen bonds between PCE and mineral mixture could be neglected. An overview of the experimental results leads to the conclusion that the adsorption of PCE onto the simulate growth ring was driven by dispersion and hydrophobic interactions. As a case study, this work will provide some information about water supply securit protection.