Insights into the life-cycle of aerobic granular sludge in a continuous flow membrane bioreactor by tracing its heterogeneous properties at different stages.

This work gave insights into the life-cycle of aerobic granular sludge (AGS) by tracing its heterogeneity in the basic properties at different stages in a closed system (a continuous flow membrane bioreactor, MBR), including physical and chemical characteristics and microbial communities. The results indicate that the entire life-cycle consists of the following four stages, namely, the initial, growing, mature and cleaved stages, where multiple AGS properties synergistically affect the rheological properties of the AGS over its life-cycle. The storage modulus (G') of AGS reached its maximum value at the mature stage, whose value was significantly and positively correlated with the protein (PN) in extracellular polymeric substances (EPS) and granule size, specifically the peak area of granule size distribution, but this value was strongly and negatively correlated with the roughness. The AGS at the mature stage would be more vulnerable to be destroyed than that at other stages under the condition of higher shear strain, such as γ = 50%, which was associated with larger granule size and fewer polysaccharide (PS)-related functional groups (especially in the soluble microbial products (SMPs) in the outermost layer of AGS), and the decrease in PS was correlated with a higher relative abundance of Chloroflexi. Additionally, the value of shear strain that AGS was subjected to had a good linear correlation (R2=0.993) with the Young's modulus, which indicated the ability of AGS to resist deformation improved with increasing values of shear strain.

Spectral change of dissolved organic matter after extracted by solid-phase extraction and its feasibility in predicting the acute toxicity of polar organic pollutants in textile wastewater.

Spectroscopic parameters can be used as proxies to effectively trace the occurrence of organic trace contaminants, but their suitability for predicting the toxicity of discharged industrial wastewater with similar spectra is still unknown. In this study, the organic contaminants in treated textile wastewater were subdivided and extracted by four commonly-used solid-phase extraction (SPE) cartridges, and the resulting spectral change and toxicity of textile effluent were analyzed and compared. After SPE, the spectra of the percolates from the four cartridges showed obvious differences with respect to the substances causing the spectral changes and being more readily adsorbed by the WAX cartridges. Non-target screening results showed source differences in organic micropollutants, which were one of the main contributors leading to their spectral properties and spectral variations after SPE in the effluents. Two fluorescence parameters (C1 and humic-like) identified by the excitation emission matrix-parallel factor analysis (EEM-PARAFAC) were closely correlated to the toxicity endpoints for Scenedesmus obliquus (inhibition ratios of cell growth and Chlorophyll-a synthesis), which can be applied to quantitatively predict the change of toxicity effect caused by polar organic pollutants. The results would provide novel insights into the spectral feature analysis and toxicity prediction of the residual DOM in industrial wastewater.

Iron-rich digestate biochar toward sustainable peroxymonosulfate activation for efficient anaerobic digestate dewaterability.

In this study, a suite of Fe-rich biochars derived from Fenton-like treated digestate (Fe-BC) were fabricated under different pyrolysis temperatures (300, 500, and 800 °C), which were firstly utilized as peroxymonosulfate (PMS) activators for promoting digestate dewaterability with wide applicability. Results showed that compared to the Fe-BC300/Fe-BC500 + PMS treatments, Fe-BC800 + PMS process performed superior digestate dewaterability in which specific resistance to filtration reduction and water content reduction improved by > 12.5% and > 130%, respectively, under the optimal conditions. Mechanistic results demonstrated that in Fe-BC800 + PMS system, HO• and SO4•- oxidation played a pivotal role on promoted digestate dewaterability, while HO• and 1O2 oxidation was dominated in Fe-BC300/Fe-BC500 + PMS treatments. Fe-BC800 containing higher Fe and CO contents could efficiently interact with PMS to generate numerous HO• and SO4•- via iron cycle. These highly reactive oxygen species proficiently reduced the hydrophilic biopolymers, protein molecules, and amino acids in extracellular polymeric substances, leading to remarkable decrease in particle size, hydrophilicity, adhesion, network strength, and bound water of digestate. Consequently, the flowability and dewaterability of digestate could be significantly enhanced. The cost-benefit result indicated the Fe-BC + PMS treatment possessed desirable reusability, applicability, and economic viability. Collectively, the Fe-BC + PMS is a high-performance and eco-friendly technique for digestate dewatering, which opens a new horizon towards a closed-loop of digestate reutilization.

Combined transcriptome and metabolome analyses reveal the mechanisms of ultrasonication improvement of brown rice germination.

This study investigated the effects of ultrasonication treatment on the germination rate of brown rice. Brown rice grains were subjected to ultrasound (40 kHz/30 min) and then incubated for 36 h at 37 °C to germinate the seeds. Ultrasonic treatment increased the germination rate of brown rice by up to ∼28 % at 30 h. Transcriptomic and metabolomic analyses were performed to explore the mechanisms underlying the effect of ultrasonic treatment on the brown rice germination rate. Comparing the treated and control check samples, 867 differentially expressed genes (DEGs) were identified, including 638 upregulated and 229 downregulated), as well as 498 differentially accumulated metabolites (DAMs), including 422 up accumulated and 76 down accumulated. Multi-omics analysis revealed that the germination rate of brown rice was promoted by increased concentrations of low-molecular metabolites (carbohydrates and carbohydrate conjugates, fatty acids, amino acids, peptides, and analogues), and transcription factors (ARR-B, NAC, bHLH and AP2/EREBP families) as well as increased carbon metabolism. These findings provide new insights into the mechanisms of action of ultrasound in improving the brown rice germination rate and candidate DEGs and DAMs responsible for germination have been identified.

Distribution characteristics of phosphorus-containing substances in a long running aerobic granular sludge-membrane bioreactor with no sludge discharge.

This work aimed at revealing the distribution characteristics of phosphorus (P) containing substances in an aerobic granular sludge-membrane bioreactor (AGS-MBR). During the long running period (180 days) with no sludge discharge, AGS was successfully cultivated on day 20, and the system performed well in removing organic pollutants and total nitrogen (TN). However, the removal of total P (TP) showed a fluctuant tendency, and P was found to distribute in all the phases of the system. In the intracellular phase, it occupied the largest ratio all through the period. In AGS, inorganic P (IP) was measured to be about 74.4-77.8% of TP, with non-apatite IP (NAIP) composing 57.5-69.6%, while in organic P (OP), the ratio of monoester and diester phosphate was in the range of 19-26.9% and 12-13.5%, respectively. The presence of highly releasable and bioavailable P (NAIP + OP) in AGS implied that it might be a potential P resource for utilization.

Towards deep purification of secondary textile effluent by using a dynamic membrane process: Pilot-scale verification.

The present investigation used regular powered activated carbon (PAC) as the dynamic membrane (DM) material and successfully built-up a pilot-scale DM system for deep purification of the secondary textile effluent, which aimed at verifying the technical and economic feasibility of the DM with real secondary textile effluent. The hydrodynamic experiments indicated that the filtration resistance gradually increased along with the operation of DM system, and among which, the PAC size was the most important influencing factor. More dosage and smaller sized PAC were beneficial to enhance the purification effect of micro-organic pollutants, but they simultaneously improved the operational costs, which implied that the adoption of DM materials should comprehensively consider the removal results and the type and dosage of DM materials for obtaining an optimal result, and the operational costs would be drastically reduced by regenerating the wasted PAC. More than 50% residual micro-organic pollutants were further removed by the system, and they were mainly some aliphatic and aromatic compounds, which were the main refractory organic pollutants in most textile effluents. It was also proved by the pilot-scale DM study that the removed residual pollutants from the secondary textile effluent were mainly aromatic protein II. Due to the contained complex functional groups in their molecular structure, soluble microbial metabolites were relatively easier to be removed by the DM layer.

Rapid granulation of aerobic granular sludge and maintaining its stability by combining the effects of multi-ionic matrix and bio-carrier in a continuous-flow membrane bioreactor.

The present investigation aimed at providing a novel approach to promote the rapid granulation and stability of aerobic granular sludge (AGS) in a continuous-flow membrane bioreactor (MBR). By operating two identical MBRs with or with no bio-carrier for 125 days, it was found that the combination of multi-ionic matrix and bio-carrier could promote the rapid formation and maintain the long-term stability of AGS. The primary AGS was first observed inside the reactor on day 14, and the mature AGS appeared soon and kept stable for more than 4 months (its average size still was about 800 µm on day 125). Suitable filling ratio of bio-carrier was beneficial to form a stable and regular circulating water flow inside, and adding divalent metal ions quickly reduced the negative charges of tiny sludge particles, which were two essential factors leading to the rapid granulation of AGS and maintaining its stability. The multi-ionic matrix not only enhanced the biological aggregation process, but also facilitated the expansion of the cultivated AGS into a new multi-habitat system of Mn-AGS, in which, complex microbial communities with rich bio-diversity robustly promoted the efficient removal of organic pollutants and nutrients.

Insights into the fouling layer of flat-sheet membrane and its development in an integrated oxidation ditch-membrane bioreactor.

This work revealed the characteristics of fouling layer on the flat-sheet membranes and its development in an integrated oxidation-ditch membrane bioreactor. During the operation period (130 days), the reactor performed very well in removing pollutants. As the operation proceeded, membrane fouling occurred on the flat-sheet membranes and trans-membrane pressure showed a cyclical variation. The experimental results showed that the process of membrane fouling appeared successively in two different structures: biofilm (BF) and sludge fouling (SF). The substances causing membrane fouling were mainly organic foulants and a small amount of inorganic metal compounds, especially the protein-like and fulvic acid-like substances in loosely bound extracellular polymeric substances (LB-EPS). The analysis of microbial communities revealed that SF and BF had very different microbial properties. Although most membrane foulants could be removed by physical and chemical cleaning methods, the protein-like and fulvic acid-like substances in BF were contribute much to causing irreversible membrane fouling.

Dewaterability improvement and environmental risk mitigation of waste activated sludge using peroxymonosulfate activated by zero-valent metals: Fe0 vs. Al0.

The stabilization and dewaterability of waste activated sludge (WAS) are essential factors for downstream disposal or reuse. Herein, two types of zero-valent metals, zero-valent iron (Fe0) and zero-valent aluminum (Al0), were compared for their ability to activate peroxymonosulfate (PMS) during the WAS conditioning process, with the effects of PMS activation by these two metals on WAS dewaterability and the potential environmental risks evaluated. Results showed that compared to Al0/PMS treatment, Fe0/PMS treatment achieved superior WAS dewaterability and reduced operational costs. Using PMS combined with Fe0 and Al0 treatments under optimal conditions, the water content (Wc) of dewatered sludge decreased to 55.7 ± 2.7 wt% and 59.4 ± 1.3 wt%, respectively. Meanwhile, application of the Fe0/PMS treatment system reduced the total annual cost by approximately 33.1%, compared to the Al0/PMS treatment. Analysis of the dewatering mechanism demonstrated that in the Fe0/PMS treatment, Fe3+/Fe2+ flocculation played an important role in the enhancement of WAS dewatering, while sulfate radical (SO4•-) oxidation was the dominant factor for WAS dewaterability improvement in Al0/PMS treatment. The greater enhancement of WAS dewaterability by Fe0/PMS treatment, was mainly attributed to more efficient reduction of hydrophilic extracellular polymeric substances (EPS) and an increase in surface charge neutralization. Environmental risk evaluation results indicated that Fe0/PMS and Al0/PMS treatments both effectively alleviated the environmental risks of heavy metals and faecal coliforms in dewatered sludge. Overall, this study proposes a novel perspective for the selection of an optimal PMS activator in sludge treatment.

Tracing the occurrence of organophosphate ester along the river flow path and textile wastewater treatment processes by using dissolved organic matters as an indicator.

Organophosphate esters (OPEs) are frequently detected in wastewater and receiving river, but their occurrence is hard to be quickly and effectively responded. In this study, the relevant OPEs and dissolved organic matters (DOMs) data were obtained from two textile wastewater treatment plants (WWTPs) with different processes and a 15 km stretch of river receiving the treated textile wastewater. UV-Vis absorption and fluorescence spectroscopy combined with peak-picking and fluorescence regional integration (FRI) methods were used to characterize DOM components in these samples. The results showed that OPEs concentrations were not always consistent with that of DOM, but were related to their physico-chemical properties and sources. Correlation and regression analysis indicated that the FRI pattern could be considered for tracing the occurrence of organophosphate diesters derived from multiple pollutants in river water, and reflected the emerging of moderate or high removal organophosphate triesters in WWTPs. Difference in the sources and DOM compositions was the main contributor to the correlation difference of OPEs and DOM in the two types of processes. The treatment technique also played important roles in the co-occurrence of OPEs and DOM in different WWTPs. This study would be beneficial to develop in-situ monitoring for the dynamic change of emerging contaminants along with a river flow path and from WWTPs, respectively.

High-level waste activated sludge dewaterability using Fenton-like process based on pretreated zero valent scrap iron as an in-situ cycle iron donator.

A novel, recyclable, and rapid pre-ultrasound-thermal-acid-washed zero valent scrap iron/hydrogen peroxide (UTA-ZVSI/H2O2) method has been developed to effectively enhance waste activated sludge (WAS) dewaterability. The effects of UTA ultrasound densities, UTA temperature, newly generated iron solution, H2O2 concentrations, and WAS conditioning time on the WAS dewaterability were investigated using a bench-scale system. Results indicated that the UTA-ZVSI/H2O2 treatment significantly improved the WAS dewaterability. The water content of the dewatered cake decreased to 44.15 ± 0.98 wt% during optimal operational conditions, which was significantly lower than that achieved using Fenton-based processes. Based on this outcome, a three-step treatment mechanism involving UTA-ZVSI/H2O2 has been developed, including iron flocculation, hydroxyl radical oxidation, and skeleton building. The dewatering efficiencies of three types of representative WAS were consistently effective in the UTA-ZVSI/H2O2 reactor for up to 15 cycles. Efficiencies levels were significantly higher than those achieved with Fenton-based processes. Economic analysis illustrated that the developed UTA-ZVSI/H2O2 system was the most cost-effective among other WAS dewatering treatments. In addition, the treatment system significantly alleviated toxicity of heavy metals and phytotoxicity in the dewatered sludge. This supported subsequent agricultural use. In summary, this study provided a comprehensive and useful basis for improving WAS dewatering and subsequent disposal.

Mechanism of zero valent iron and anaerobic mesophilic digestion combined with hydrogen peroxide pretreatment to enhance sludge dewaterability: Relationship between soluble EPS and rheological behavior.

This study proposed a novel two-step conditioning strategy to enhance activated sludge (AS) dewatering performance. The method involved a zero valent iron (ZVI), anaerobic mesophilic digestion (AMD) process, and hydrogen peroxide (H2O2) oxidation. Response surface methodology (RSM) was applied to achieve optimum dewatering conditions. After the combined conditioning, dewatering was significantly better in the treated sludge compared to the raw AS. The specific resistance of filtration (SRF) of the treated sludge decreased to 2.48 × 1011 m/kg; this SRF level was 93.60% lower compared to the raw AS. The bound water content (BWC) decreased to 1.19 g/g dry solid (DS); this BWC level was 15.2% lower compared to the raw AS. The water content of the treated sludge cake decreased to 44.18 ± 0.46%. An economic analysis shows that ZVI-AMD-H2O2 can be used in real-world settings. Investigations of the underlying mechanisms showed that small block structures were formed after conditioning; viscosity and the colloidal forces of the sludge decreased; and organic matter and BWC were released from inner extracellular polymeric substances (EPS) layers to form soluble (SB)-EPS. This study illuminated the relationship between SB-EPS and the rheological behavior of AS. There is a high correlation coefficient between rheological parameter τy and N-containing substances in SB-EPS (R = -0.993, p < 0.05). The ZVI-AMD-H2O2 process effectively changed the EPS content, especially protein materials. This led to a decrease in AS viscosity and an increase in sludge dewaterability.

Occurrence, ecotoxicological risks of sulfonamides and their acetylated metabolites in the typical wastewater treatment plants and receiving rivers at the Pearl River Delta.

Sulfonamides (SAs) were frequently detected in various environmental water bodies because of their incomplete removal during wastewater treatment process, and this may lead to a negative effect on aquatic ecosystems. This study investigated six SAs and three of their acetylated metabolites in the influents, effluents, and the receiving river waters from four typical wastewater treatment plants (WWTPs) at the Pearl River Delta in Guangdong province, China. The results indicated that sulfadiazine, sulfapyridine and sulfamethoxazole had the highest detection frequency. Moreover, sulfadiazine and sulfamethoxazole had its maximum concentrations (216 ng/L and 200 ng/L, respectively) in the influent during dry season. To evaluate the compound degradability, the removal efficiency of each individual sulfonamide was calculated, and a modified method to assess it was recommended considering the widespread inter-conversion between SAs and their metabolites. Finally, regarding the effluent and river water, potential environmental risk based on the Hazard quotients (HQs) was estimated towards three diverse non-targeted organisms. Sulfamethoxazole was assessed with the highest HQ (>3.6), being the sole sulfonamide that would pose a risk to algae in the effluents and river waters. Thus, SAs emission needs to be further reduced from WWTPs into the environment.

Promoting the granulation process of aerobic granular sludge in an integrated moving bed biofilm-membrane bioreactor under a continuous-flowing mode.

This investigation demonstrated that aerobic granular sludge (AGS) could be cultivated rapidly in a single continuous-flowing membrane bioreactor (MBR) by introducing freely moved bio-carriers with a filling ratio of 10%. By operating the bioreactor for 28 days, AGS was successfully cultivated and kept stable for >2 months with a compact structure and clear shape, in which, extracellular polymeric substances played a key role in maintaining the stability of granular sludge structure. The microbial composition between AGS and attached biofilm was quite different, which indicated that the introduced bio-carriers improved the biodiversity within the bioreactor. Additionally, an explicit internal circulation was formed by the introduced bio-carriers, which was the main reason leading to the rapid formation of AGS. This is an interesting discovery and a novel approach to promote the rapid granulation of biomass in an MBR. Moreover, combining the biodegradation of AGS and filtration of membrane module, the bio-reactor achieved an excellent performance in removing CODCr (>90%) and TN (>85%) during the whole process.

Build-up of a continuous flow pre-coated dynamic membrane filter to treat diluted textile wastewater and identify its dynamic membrane fouling.

This research built up a continuous dynamic flow filter membrane to treat diluted textile wastewater and basically investigated dynamic membrane fouling mechanism. By pre-depositing particles activated carbon (PAC) on membrane support material (MSM), a thin layer was formed on its surface, which showed excellent results in removing organic pollutants from diluted textile wastewater. Experimental data were regressed by the Langmuir, Freundlich, Temkin, Dubinin-Radushkevich (D-R) and Sips isotherm models. The three two-parameter isotherms (Temkin, D-R and Freundlich) were the models that best fitted, with respectively 0.977, 0.975 and 0.973 regression coefficients. D-R model has registered the maximum calculated adsorption capacity Qmd, cal. = 45.499 mg/g and the mean energy which was required to adsorb 1 mol of MB dye by the DM layer E = 4.249 kJ/mol; indicating the energy distribution onto heterogeneous surface of a physical adsorption process. Furthermore, kinetic models results showed that MB adsorption onto PAC at different initial concentrations follows the pseudo-second order. The obtained results also indicated that a flexible DM layer with different thickness can be formed from different amount of PAC pre-deposited on MSMs, which demonstrated that it was convenient to adjust the required DM thickness to filtrate a known initial concentration for >99% organic pollutants removal efficiency rate. However, DM fouling occurred on small pores MSMs; which resulted in an increase of the filtration pressure what have affected the filtration performance. PAC and MSMs surface morphology and texture structure, before and after filtration, were visualized respectively by Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infra-Red and Attenuated Total Reflectance (FTIR/ATR). From these experimental results, a sustainable flux (>6.85 × 10-5 m/s) was established to discriminate no fouling from fouling conditions based on flux and TMP trends variance.

Analysis of the relationship of extracellular polymeric substances to the dewaterability and rheological properties of sludge treated by acidification and anaerobic mesophilic digestion.

The initial pH value of sludge affects sludge anaerobic digestion and dewatering performance. In order to determine the suitable pH value and decrease the sludge digestion time, in this study, the effect and the mechanism of combined acidification and anaerobic mesophilic digestion (acid-AMD) on sludge dewaterability were investigated. The changes and relationships among the extracellular polymeric substances (EPS), physicochemical properties, and rheological behavior of the treated sludge were analyzed. The results indicated that the combined acid-AMD treatment improved sludge dewaterability approximately 36.08% and 30.28% compared to the acid conditioning and AMD treatment, respectively. The factors improving sludge dewaterability include a lower sludge pH value and appropriate duration of AMD, changes in particle size, surface properties and distribution of the EPS fractions. The acid-AMD treatment hydrolyzed the EPS, loosening the sludge structure. These changes reflected in the rheological properties of the sludge. After the treatment, the network strength and colloid force of the sludge weakened. The linear viscoelastic region contracted, and the sludge system became sensitive to shear. These results demonstrated that rheological analysis can help explain the sludge dewatering mechanism. The acid-AMD treatment effectively changed the distribution of EPS that play a vital role in sludge dewaterability.

Residual micro organic pollutants and their biotoxicity of the effluent from the typical textile wastewater treatment plants at Pearl River Delta.

This work investigated the biotoxicity and the residual dissolved organic matter (DOM) of the effluents from nine typical full-scale textile plants located at Pearl River Delta (PRD) in Guangdong province, China. The fluorescence regional integration (FRI) analysis showed that the tryptophan-like (II), soluble microbial product-like (IV) and fulvic acid-like substances (III) were the dominant compounds in the DOM. The acute toxicity test showed toxic effects still remained in most textile effluents, which might attribute to the undegraded dyes or aromatic compounds. Combining with the results from multiple methods, it indicated that the selected nine textile wastewater treatment plants (tWWTPs) all contained some residual micro organic pollutants in their effluents, and the residual benzene-derived products or aromatic amines were probably the toxicity-causing substances. Both ozonization and membrane filtration were capable of further decreasing the content of residual DOM, but by comprehensively considering the effects of removing DOM and biotoxicity, membrane filtration was better than ozonization.

Flot2 targeted by miR-449 acts as a prognostic biomarker in glioma.

Flotillin-2 (FLOT2) was reported as oncogene and involves in the pathogenic process of several cancers, yet the precise mechanism of FLOT2 in glioma is still limited. In this study, we demonstrated that FLOT2 expression levels were greatly upregulated in glioma tissues and cell lines, and the FLOT2 expression in glioma tissue was markedly associated with tumour stage and size. Overexpression of FLOT2 was correlated with poor prognosis of glioma patients. The functional assay revealed that silenced FLOT2 repressed the viability, migration, and invasion of glioma cells. And then, we detected the relationship between miR-449 and FLOT2. Luciferase reporter assay and Western blot results showed that miR-449 directly binding the 3'UTR sequence of FLOT2 and regulated FLOT2 expression in glioma cells. Finally, we detected the expression levels of miR-449 in glioma tissue and cell lines and found that miR-449 was significantly downregulated in glioma tissues and cell lines. In conclusion, we demonstrated that overexpression FLOT2 was associated with poor prognosis of glioma patients and involved in the progression of glioma, identifying a novel prognostic biomarker and therapeutic target for glioma progression.

Rapid reformation of larger aerobic granular sludge in an internal-circulation membrane bioreactor after long-term operation: Effect of short-time aeration.

The investigation aimed at revealing the influence of an external disturbance on the rapid reformation of larger aerobic granular sludge (AGS) in an internal-circulation membrane bioreactor (IC-MBR) after long-term operation. The used IC-MBR was continuously operated well for more than one year, in which, the biomass was still in the state of AGS with a balanced average size at around 200 µm and an even size distribution. By providing short-time aeration to the biomass within this bioreactor, the characteristics of biomass were totally changed in a very short time, including the surface hydrophilicity, physic-chemical properties, and the structure of microbial community, which created suitable conditions for the growth of filamentous bacteria (Saccharibacteria). Such a variation was very beneficial to the reformation of larger AGS, which resulted in the average size of AGS increased to nearly 400 µm with a compact structure and clear edge in no more than one month.

Heterogeneity of the diverse aerobic sludge granules self-cultivated in a membrane bioreactor with enhanced internal circulation.

The present work revealed the heterogeneity of the sludge granules formed in a membrane bioreactor with enhanced internal circulation, and also contributed to better understanding of their forming mechanisms. By continuously carrying out an experiment lasting for more than 3 months with the floc sludge from a local municipal wastewater treatment plant as inoculation sludge, diverse aerobic sludge granules were found to be successfully self-cultivated within the reactor. The results of scanning electron microscopy, fluorescence microscope and high-throughput sequencing measurement indicated that the obtained diverse granules exhibited quite obvious heterogeneity in their basic physico-chemical and microbial properties, and filamentous bacteria actually acted as a main skeleton to keep the self-cultivated sludge granules stable in both their structure and morphology. Furthermore, stable and high COD and TN removal achieved, over 85% and 60%, respectively, which confirmed its usefulness in wastewater treatment.