Search

Floating phytoremediation offers a feasible, ecofriendly, and economically viable method for treating wastewater. The objective of this study is to assess the effectiveness of Eichhornia crassipes and Pistia stratiotes in treating domestic wastewater by varying loading strength and hydraulic retention time (HRT). The growth parameters of the plants were assessed and linked to the removal of contaminants. The wastewater phytoremediation by E. crassipes and P. stratiotes conducted for twenty-two days in a green house. Result showed that Eichhornia crassipes able to treat 50% strength of wastewater (50WH) efficiently with removal of ammonia, phosphate, and COD by 97.4%, 68.5%, and 54.0%, respectively, at the HRT of three days. The 50WH experimental units showed the lowest relative growth rate (RGR). The results proved the higher efficiency of E. crassipes in treating the domestic wastewater.

In this study, biosorption potential of nine epiphytic bacteria isolated from the rhizosphere of Lepironia articulata and Scirpus grossus were assessed. Identification of the isolated epiphytic rhizobacteria using 16S rRNA analysis showed species belonging to the four genera of Bacillus, Enterobacter, Aeromonas, and Chromobacterium. Batch biosorption studies were carried out to assess the capacity of the isolated bacteria to act as Pb and Cu biosorbents. Different initial concentrations of the two heavy metals (50, 100, 200, 300, and 400 ppm) were used to determine the ability of the biosorbent to reach a tolerance level and then calculate the percentage of biosorption with respect to 0.1 g dry weight. Initial concentration of Pb and Cu exposed showed that the isolated bacteria have high tolerance up to 400 ppm. Bacteria prefer Pb ions over Cu, which is indicated by higher removal of Pb in all tested reactors. Bacillus sp. (coded Sc1) showed the highest biosorption capacity with 100% Pb and 97% Cu removal.

The ability of mixed neem, cassava, and wild betel plant leaves to act as plant-based coagulants was tested in real aquaculture wastewater through the coagulation-flocculation process. The performance of plant-based coagulant (PBC) was compared with that of chemical coagulant (alum) to observe the removal efficiency of turbidity, TSS, color, and COD. Ratio, as a new approach, was used by selecting TSS as an indicator or index to substitute for the dosage term and calculated based on a simplified equation. The extracted medium for these coagulants was prepared by using water extraction. Initial characterizations showed that the PBC had some carbon and amine groups (as also confirmed by LC-MS) with an average zeta potential of –22.83 ± 0.62 mV. Results indicated both coagulants (plant-based and chemical coagulants) successfully removed the measured polluted parameters of turbidity (85.17 %), TSS (80.28 %), color (59.42 %), and COD (54.63 %) for PBC with dosage of 0.79 mg/L and coagulant mass of 3.94 mg, while alum gained a higher removal with turbidity (99.08 %), TSS (98.71 %), color (97.29 %), and COD (75.31 %) with dosage and coagulant mass of 698.4 mg/L and 349.2 mg, respectively. This signaled that alum still acted as the best coagulant, but PBC showed a promising opportunity as a potential substitute for chemical coagulant.

The present study investigated the utilization of blood clam shells as a potential substitute for conventional media, as well as the influence of the acclimation time on the efficacy of an intermittent slow sand filter (ISSF) in the treatment of real domestic wastewater. ISSF was operated with 16 h on and 8 h off, focusing on the parameters of turbidity, ammonia, and phosphate. Two media combinations (only blood clam shells [CC] and sand + blood clam shells [SC]) were operated under two different acclimatization periods (14 and 28 d). Results showed that SC medium exhibited significantly higher removal of turbidity (p 0.05) removal of ammonia (23.12 ± 20.2 % vs. 16.77 ± 16.8 %) and phosphate (18.03 ± 11.96 % vs 13.48 ± 12 %). Comparing the acclimatization periods, the 28 d of acclimatization period showed higher overall performances than the 14 d. Further optimizations need to be conducted to obtain an effluent value below the national permissible limit, since the ammonia and phosphate parameters are still slightly higher. SEM analysis confirmed the formation of biofilm on both mediums after 28 d of acclimatization; with further analysis of schmutzdecke formation need to be carried out to enrich the results.

Biocoagulants have gained attention as an alternative to chemical coagulants in water and wastewater treatment due to their ability to remove pollutant parameters such as turbidity, suspended solids, color, and organic compounds. Plant-based biocoagulants are currently the most promising due to their abundant availability and reliable performance. A proper preparation of plant-based biocoagulants is required to ensure the active compounds from the plants can be extracted. Plant raw materials are prepared into biocoagulants using drying and grinding, extraction, and purification. In mechanical preparation, drying and grinding exhibit great influence on the performance of plant-based biocoagulants due to the removal of moisture and higher contact with the carrier medium during dissolution. A smaller biocoagulant's size resulted in up to 78 % higher removal of turbidity. In chemical preparation, the oil needs to be removed before extracting the active ingredients to avoid low active compound extraction yields. The defatting of Moringa oleifera seeds showed an 18 % higher protein content. Salt and alcohol extractions were mentioned as superior extraction methods to obtain carbohydrate and protein from plant-based biocoagulants compared to water extraction, with up to a 5 % increment in turbidity removal. Preparation and pretreatment protocols have a great influence on the properties and performance of plant-based biocoagulants. Further extension of research on plant-based biocoagulants should address the problems in the initial characterization of plant material, standard pretreatment and preparation protocols, and real-scale application of plant-based biocoagulants.

Phytoremediation is one of the green technologies that is friendly to nature, utilizes fewer chemicals, and exhibits good performance. In this study, phytoremediation was used to treat diesel-contaminated sand using a local aquatic plant species, Scirpus mucronatus, by analyzing the amount of total petroleum hydrocarbons (TPHs). Optimization of diesel removal was performed according to Response Surface Methodology (RSM) using Box-Behnken Design (BBD) under pilot-scale conditions. The quadratic model showed the best fit to describe the obtained data. Actual vs. predicted values from BBD showed a total of 9.1 % error for the concentration of TPH in sand and 0 % error for the concentration of TPH in plants. Maximum TPH removal of 42.3 ± 2.1 % was obtained under optimized conditions at a diesel initial concentration of 50 mg/kg, an aeration rate of 0.48 L/min, and a retention time of 72 days. The addition of two species of rhizobacteria (Bacillus subtilis and Bacillus licheniformis) at optimum conditions increased the TPH removal to 51.9 ± 2.6 %. The obtained model and optimum condition can be adopted to treat diesel-contaminated sand within the same TPH range (50–3000 mg/kg) in sand.

Floating aquatic macrophytes have a high level of proficiency in the removal of various contaminants, particularly nutrients, from wastewater. Due to their rapid growth rates, it is imperative to ensure the safe removal of the final biomass from the system. The ultimate macrophyte biomass is composed of lignocellulose and has enhanced nutritional and energy properties. Consequently, it can serve as a viable source material for applications such as the production of bioenergy, fertilizer and animal feed. However, its use remains limited, and in-depth studies are scarce. Here, we provide a comprehensive analysis of floating aquatic macrophytes and their efficacy in the elimination of heavy metals, nutrients and organic pollutants from various types of wastewater. This study offers a wide-ranging scrutiny of the potential use of plant biomasses as feedstock for bioenergy generation, focusing on both biochemical and thermochemical conversion processes. In addition, we provide information regarding the conversion of biomass into animal feed, focusing on ruminants, fish and poultry, the manufacture of fertilizers and the use of treated water. Overall, we offer a clear idea of the technoeconomic benefits of using macrophytes for the treatment of wastewater and the challenges that need to be rectified to make this cradle-to-cradle concept more efficient.

The batik industry has been one of the main family businesses in most of the east-coast region of the Malaysian peninsula for many years. However, appropriate water treatment is still a major challenge for this industry. Stringent laws introduced by the Malaysian authorities and the intention to protect the environment are factors that drive researchers to search for suitable, appropriate, affordable and efficient treatment of batik wastewater. Treatment research on batik wastewater is still lacking and coagulation-flocculation treatment using alum was introduced and chosen as a stepping stone toward the selection of green coagulants. This study aimed to determine the best conditions for alum flocculation-coagulation using a standard jar test method. Four main factors were investigated: alum dosage (0.1–3.5 g/L), pH (4–11), settling time (0.5–24 h) and rapid mixing rate (100–300 rpm). Results obtained were further analysed statistically using SPSS software prior to determining the significant effect of variable changes. From this study, the best conditions for batik wastewater treatment using the flocculation-coagulation process were found to be at alum dosage of 1.5 g/L, pH 8, 4 h settling time and a rapid mixing rate of 100 rpm. Chemical oxygen demand (COD), turbidity, colour and total suspended solids (TSS) were removed by 70.7, 92.2, 88.4 and 100%, respectively, under these conditions. This study showed that batik wastewater can be treated by the coagulation-flocculation process using chemical means of alum. This indicates the need for forthcoming developments in natural-based-coagulant-flocculants toward the sustainability of the batik industry.

Urban industrialization has caused a ubiquity of microplastics in the environment. A large percentage of plastic waste originated from Southeast Asian countries. Microplastics arising from the primary sources of personal care items and industrial uses and the fragmentation of larger plastics have recently garnered attention due to their ubiquity. Due to the rising level of plastic waste in the environment, the bioaccumulation and biomagnification of plastics threaten aquatic and human life. Wastewater treatment plant (WWTP) effluents are one of the major sources of these plastic fragments. WWTPs in Southeast Asia contribute largely to microplastic pollution in the marine environment, and thus, further technological improvements are required to ensure the complete and efficient removal of microplastics. Coagulation is a significant process in removing microplastics, and natural coagulants are far superior to their chemical equivalents due to their non-toxicity and cost-effectiveness. A focused literature search was conducted on journal repository platforms, mainly ScienceDirect and Elsevier, and on scientific databases such as Google Scholar using the keywords Wastewater Treatment Plant, Coagulation, Microplastics, Marine Environment and Southeast Asia. The contents and results of numerous papers and research articles were reviewed, and the relevant papers were selected. The relevant findings and research data are summarized in this paper. The paper reviews (1) natural coagulants for microplastic removal and their effectiveness in removing microplastics and (2) the potential use of natural coagulants in Southeast Asian wastewater treatment plants as the abundance of natural materials readily available in the region makes it a feasible option for microplastic removal.

Unless better measures are put in place to address the environmental and social impacts emanating from the huge waste generated from sea food processing industries; ‘tragedy of the commons’ is inevitable. Needless to re-emphasise the enormous contributions of aquaculture as the perfect substitute to capture fisheries which has been proven unsustainable. Be that as it may, the huge amount of bio-waste produced could be transformed into useful products such as chitin and chitosan with far reaching applications. Chitin and chitosan have been consistently processed from many sources following the traditional chemical sequence of Demineralization (DM), Deproteinization (DP), Decolouration (DC) and Deacetylation (DA). In this study, this method was re-ordered, resulting to 4 sequences of chemical processes. HCl, NaOH, ethanol (97%) and NaOH (50%) were used for DM, DP, DC and DA respectively. The results of this study showed that better chitin (23.99 ± 0.61%) and chitosan (15.17 ± 1.69%) yields were obtained from sequence four (SQ4) following the order of DC-DM-DP-DA. In addition, physicochemical properties such as DDA (80.67 ± 2.52%) and solubility (66.43 ± 2.61%) were significantly higher (p ≤ 0.05) in SQ4 thereby making the obtained product suitable for use as coagulant and flocculant in wastewater treatment. Results of FTIR, XRD and SEM of the study proved that the resultant product exhibited the characteristic nature of chitosan with porous and fibril nature. In the analysis of the physical properties of chitosan obtained from bio-waste of Macrobrachium rosenbergii, the high Carr's index (CI) and low bulk as well as tapped densities were an indication that the chitosan produced in this study had poor flowability and compressibility, thereby making it unfit for application in pharmaceutical industries.

The negative impacts of aquaculture wastewater can best be curtailed by sustainable treatment before discharge. As far as environmental safety is concerned, there is no safer place where floc recovered from the treatment of aquaculture wastewater can be disposed. Therefore, it has become imperative to find a more sustainable way of recycling the floc in a manner that ensures environmental protection and other economic benefits. In the present study, chitosan from Macrobrachium rosenbergii was used in the recovery of floc from shrimp aquaculture wastewater. Optimization of dosage, pH and settling time were performed using RSM where percentage turbidity and TSS removal were tested. Recovered floc was analyzed for plant nutrients and further applied as organic fertilizer for growth enhancement of Water spinach, Ipomea aquatica. Results showed that chitosan removed 92.45% turbidity at 12.5 mg/L dosage and 6.88 pH after 30min. Settling time. Similarly, 69.49% TSS removal was achieved with dosage of 8.75 mg/L at 5.67 pH and 5min. Settling time. The plant nutrient analysis of floc revealed the presence of N, P, K, Ca, Mg Zn, Cu, Mn, Fe, Ni, Se Co Pb, Cr, Al, and As. Furthermore, this study showed that plant treated with floc outperformed other treatments in terms of root volume and length, plant height, leaf count, fresh and dry mass. It was concluded that the nutrients were readily available for the absorption and growth of plants. In addition, the higher growth performance of plants treated with floc was attributed to the higher N level (6.04%) in the floc as compared to other treatments.

A pressing concern of issues such as climate change has drawn main attention in the world. The burning of fossil fuels by human due to increasing energy demand in various sectors is one of the main factors that influence the climate change. This has resulted in the introduction of many renewable energy sources as alternatives to fossil fuels. Biogas is one type of renewable energy that has numerous advantages. The present review covers the recent challenges of biogas production and its conversion to electrical energy. This includes the substrates used, the operating parameters, and the pre-treatment used, which can be implemented to maximise the biogas yield. The challenges and potential of the generation of electricity from biogas were also discussed in this review. The results obtained in this review emphasise that biogas is a good renewable energy, as it solves multiple problems and at the same brings benefits to human beings in many ways.

Bisphenol A (BPA) is widely used in everyday life and can be found everywhere, including in the ecosystem and manufactured goods. BPA not only has a negative impact in low doses, but it also has biological and pathophysiological implications for obesity and hormonal effects. The objectives of this paper were to review the BPA removal technology and the factors that influence the BPA removal based on biological methods. BPA elimination from water is crucial for environmental protection, in terms of biological treatment. In addition, the future prospect of biological removal of BPA indicates that effective microorganism cultures could disturb the pathogen growth and increase composition rate of BPA. The biological technology by the implementation of microorganisms for the removal of BPA through break down of organic contaminants is straightforward, money saving, and widely acknowledged by the public.

Phytoremediation is an eco-friendly biotechnology with low costs. The removal of copper (Cu) from polluted water by the two floating plant species Azolla filiculoides and Lemna minor was observed and recorded. Plants were exposed to different Cu (II) concentration (0.25–1.00 mg/L) and sampling time (Days 0, 1, 2, 5 and 7). Both plants can remove Cu at 1.00 mg Cu/L water, with the highest removal rates of 100% for A. filiculoides and 74% for L. minor on the fifth day of exposure. At the end of the exposure period (Day 7), the growth of A. filiculoides exposed to 1.00 mg Cu/L was inhibited by Cu, but the structure of the inner cells of A. filiculoides was well organized as compared to the initial treatment period. Regarding L. minor, Cu at 1.00 mg/L negatively impacted both the growth and morphology (shrinking of its inner structure) of this plant. This is due to the higher accumulation of Cu in L. minor (2.86 mg/g) than in A. filiculoides (1.49 mg/g). Additionally, the rate of Cu removal per dry mass of plant fitted a pseudo-second order model for both plants, whereas the adsorption equilibrium data fitted the Freundlich isotherm, indicating that Cu adsorption occurs in multiple layers. Based on the results, both species can be applied in the phytoremediation of Cu-polluted water.

Influenza virus is a life-threatening pathogen that infects millions of people every year, with annual mortality in the hundreds of thousands. The scenario for controlling infection has worsened with increasing numbers of vaccine hesitancy cases reported worldwide due to objections on safety, religious and other grounds. Uses of haram (impermissible) and mashbooh (doubtful) ingredients in vaccine production has raised doubts among Muslim consumers and consequently stimulated serious vaccine hesitancy. To address this major problem, we have reviewed and recommended some alternatives appropriate for manufacturing cell-based influenza vaccine which comply with Islamic laws and consumers’ needs. Intensive assessments of current influenza vaccine production in both scientific and Islamic views have led to the identification of four main ingredients deemed impermissible in novel sharia-compliant (approved by Islamic laws) vaccine manufacturing. Only some of these impermissible components could be replaced with halal (permissible) alternatives, while others remain impermissible due to unavailability and unsuitability.

The use of microalgae for CO2 sequestration helps in mitigating global warming. This paper reviews the application of microalgae for CO2 sequestration with emphasis on performance evaluation, lifecycle, economic assessment, as well as environmental impact. The CO2 sequestration mechanism is done during photosynthesis, via bioconcentration. Performance evaluation revealed that the efficiency of capture and sequestration of CO2 by microalgae ranges between 40% and 93.7%. However, the macro performance of microalgae in carbon emission reduction has not yet been fully understood, and therefore requires more studies. Also, the cost-effectiveness of the CO2 sequestration by microalgae cultivation still needs more research based on recent economic realities. It is recommended that design and operation be focused on cost-effectiveness so the technology can compete favourably with existing technologies. Overall, it can be surmised that the application of microalgae for CO2 sequestration is an effective technique for carbon capture, but still has interesting areas for development for greater global environmental impact.

The study aims to select suitable ornamental plant species that can survive relatively with high concentrations of acetaminophen and methylparaben in constructed wetlands. Alternanthera spp, Asparagus aethiopicus and Chlorophytum comosum are examined to withstand three initial concentrations, 20, 100 and 200 mg/L of acetaminophen and methylparaben. A total of 21 plastic pails with each 3 L capacity consisting of nine pails are used for each pharmaceutical and personal care products (PPCPs) compounds (acetaminophen and methylparaben) for three ornamental plants (Alternanthera spp, Asparagus aethiopicus and Chlorophytum comosum), with three pails as plant controls. The results reveales that both Alternanthera spp and Chlorophytum comosum exhibite a good tolerance for acetaminophen with a reduction in the total chlorophyll content of about 4.4–12.3% and 3.9–31.9% for Alternanthera spp and Chlorophytum comosum, respectively. Moreover, it is evident that high concentrations (100 and 200 mg/L) of methylparaben adversely affects the chlorophyll content of the three involved plant species. These results indicate that ornamental plants play an important role in the phytoremediation of PPCPs and can be considered as an esthetic treatment for hospital wastewater.

Seashells waste is abundant in coastal area, especially in the locations where fisheries are a major occupation. This abundant resource of seashells opens a new opportunity further utilization. Seashells waste is a source of CaCO3, which may be converted into CaO via the calcination process. This study analyzed the characteristics of the CaO produced via calcination process at different temperature and calcination time. The calcination process was carried out at a temperature of 800oC, 900oC, and 1000oC with variation of 2, 3, and 4 hours in time. The Fourier transform infrared spectroscopy (FTIR) result showed that the spectrum of 2513 cm-1 as an indication of the C-H group containing CaO appearing after calcination. The FTIR results suggest that the calcination time did not gave major alteration to the functional groups. The results of X-ray diffraction (XRD) analysis showed that CaO laid at the angle of 58.1o and 64.6o. Scanning Electron Microscopy - Energy Dispersive X-Ray Spectroscopy (SEM-EDS) results showed that the most significant compositional outcome after the calcination process was Ca and O at all temperatures and calcination times. All calcined seashells showed rough surface and irregular shape particles. The result of a Thermogravimetric analysis (TGA) suggested that the highest mass alteration occurred at a temperature of 800°C with 78 mins of calcination time.

Bioaugmentation, the addition of cultured microorganisms to enhance the currently existing microbial community, is an option to remediate contaminated areas. Several studies reported the success of the bioaugmentation method in treating heavy metal contaminated soil, but concerns related to the applicability of this method in real-scale application were raised. A comprehensive analysis of the mechanisms of heavy metal treatment by microbes (especially bacteria) and the concerns related to the possible application in the real scale were juxtaposed to show the weakness of the claim. This review proposes the use of bioaugmentation-assisted phytoremediation in treating heavy metal contaminated soil. The performance of bioaugmentation-assisted phytoremediation in treating heavy metal contaminated soil as well as the mechanisms of removal and interactions between plants and microbes are also discussed in detail. Bioaugmentation-assisted phytoremediation shows greater efficiencies and performs complete metal removal from soil compared with only bioaugmentation. Research related to selection of hyperaccumulator species, potential microbial species, analysis of interaction mechanisms, and potential usage of treating plant biomass after treatment are suggested as future research directions to enhance this currently proposed topic.

Abstract Leachate is produced from sanitary landfills containing various pollutants, including heavy metals. This study aimed to determine the resistance of bacteria isolated from non-active sanitary landfill leachate to various heavy metals and the effect of salinity levels on the removal of Hg by the isolated bacterium. Four dominant bacteria from approximately 33 × 1017 colony-forming units per mL identified as Vibrio damsela, Pseudomonas aeruginosa, Pseudomonas stutzeri, and Pseudomonas fluorescens were isolated from non-active sanitary landfill leachate. Heavy metal resistance test was conducted for Hg, Cd, Pb, Mg, Zn, Fe, Mn, and Cu (0–20 mg L− 1). The removal of the most toxic heavy metals by the most resistant bacteria was also determined at different salinity levels, i.e., fresh water (0‰), marginal water (10‰), brackish water (20‰), and saline water (30‰). Results showed that the growth of these bacteria is promoted by Fe, Mn, and Cu, but inhibited by Hg, Cd, Pb, Mg, and Zn. The minimum inhibitory concentration (MIC) of all the bacteria in Fe, Mn, and Cu was > 20 mg L− 1. The MIC of V. damsela was 5 mg L− 1 for Hg and > 20 mg L− 1 for Cd, Pb, Mg, and Zn. For P. aeruginosa, MIC was > 20 mg L− 1 for Cd, Pb, Mg, and Zn and 10 mg L− 1 for Hg. Meanwhile, the MIC of P. stutzeri was > 20 mg L− 1 for Pb, Mg, and Zn and 5 mg L− 1 for Hg and Cd. The MIC of P. fluorescens for Hg, Pb, Mg, and Zn was 5, 5, 15, and 20 mg L− 1, respectively, and that for Cd was > 20 mg L− 1. From the MIC results, Hg is the most toxic heavy metal. In marginal water (10‰), P. aeruginosa FZ-2 removed up to 99.7% Hg compared with that in fresh water (0‰), where it removed only 54% for 72 h. Hence, P. aeruginosa FZ-2 is the most resistant to heavy metals, and saline condition exerts a positive effect on bacteria in removing Hg.

Improperly treated heavy metal wastewater discharged into water sources could cause a serious issue for the environment. The aim of this study was to bioaccumulate iron (Fe) using native bacteria isolated from the laboratory drainage water containing a high concentration of iron. The experiment was conducted in 250 mL conical flasks containing 150 mL Fe solution in concentrations of 25, 100, and 250 mg/L, respectively. Approximately 10% of bacteria inoculum was cultivated in each Fe concentration for 24 and 48 hours. The results showed that Pseudomonas hibiscicola was identified as an effective iron-accumulating species of bacteria. The species could remove Fe up to 82% (25 mg/L), 77.8% (100 mg/L) and 32% (250 mg/L). This promising result indicates that the native bacteria isolated from the environment pose a great potential for the remediation of wastewater containing iron.

The major sources of waste from aquaculture operations emanates from fish or shellfish processing and wastewater generation. A simple technique called coagulation/flocculation utilizes biowaste from aquaculture to produce chitosan coagulant for wastewater treatment. A chemical method was applied in the present study for chitin and chitosan extraction from carapace of Macrobrachium rosenbergii and subsequent application for removal of turbidity and salinity from shrimp aquaculture wastewater. Box-Behnken in RSM was used to determine the optimum operating conditions of chitosan dosage, pH, and settling time, after which quadratic models were developed and validated. Results show that 80 g of raw powder carapace yielded chitin and chitosan of 23.79% and 20.21%, respectively. The low moisture (0.38%) and ash (12.58%) content were an indication of good quality chitosan, while other properties such as water-binding capacity (WBC), fat-binding capacity (FBC), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscope (SEM) confirmed the structure and the α-group, as well as the rough morphology of chitosan. In addition, the high solubility (71.23%) and DDA (85.20%) suggested good coagulant potentials. It was recorded in this study that 87.67% turbidity was successfully removed at 20 mg/L of chitosan dosage and 6.25 pH after 30 min settling time, while 21.43% salinity was removed at 5 mg/L of chitosan dosage, 7.5 pH, and 30 min settling time. Therefore, the process conditions adopted in this study yielded chitosan of good quality, suitable as biopolymer coagulant for aquaculture wastewater treatment.

Dyes are considered to be hazardous, have low biodegradability and can affect human health as well as the aquatic life cycle. This research investigated methylene blue (MB) removal using an activated carbon matrix of Scirpus grouss (waste that was initially used for phytoremediation of soil). The experiment was conducted in a flask containing 0.5 g AC-SC with MB concentrations of 5 and 15 mg/L. The adsorption was monitored for 120 sec. The results showed complete removal of MB within a contact time of 30 sec using 6-AC. Surface morphology analysis showed that at 6-AC the structure was more porous. The ultimate potential of activated carbon prepared from the phytoremediation plant waste would be the best alternative for water and wastewater treatment, while it provides the alternative of phytoremediation waste management process.

Since the implementation of the International Maritime Organization 2004 regulation, most ships have been equipped with on-dock ballast water treatment. While this method is effective in solving the invasive alien species problem, concerns are raised due to the potential release of disinfection by-products (DBPs) as the result of the chemical treatment. This review paper aims to summarize the history of ballast water management (BWM) and the currently used on-dock technology. Chlorination, oxidation, and ozonation are highlighted as the most currently applied methods to treat ballast water on-dock. This paper then focuses on the potential release of toxic DBPs as the result of the selected corresponding treatment methods. Tri-halo methane, haloacetic acid, and several acetic acid-related compounds are emphasized as toxic DBPs with concentrations reaching more than 10 μg/L. The potential toxicities of DBPs, including acute toxicity, carcinogenicity, genotoxicity, and mutagenicity, to aquatic organisms, are then discussed in detail. Future research directions related to the advanced treatment of DBPs before final discharge and analysis of DBPs in coastal sediments, which are barely studied at present, are suggested to enhance the current knowledge on the fate and the ecological impact of BWM.

Water pollution is one of the global challenges that the society must address in the 21st century aiming to improve the water quality, reduce human pollutants and ecosystem health impacts. In phytotoxicity test, the plant of Iresine herbstii was exposed to remove nickel from simulated wastewater using two different ratios (mass of plant to the mass of nickel) (,Rp/Ni) for 21 days with sub-surface batch system. During the exposure period, the removal of Ni concentrations (2, 5 and 10 mg/L) for two mass ratio (2,800 and 34,000) were (83.6%, 77.2%, 78.0%) and (86.8%, 97% and 95.6%), respectively. final result of the rate was found that the highest removal occurred, 97%, at a mass ratio of 34,000 and a nickel concentration of 5 mg/L. Metal accumulation mechanism of plants were examined using bioconcentration factor (BCF) and translocation factor (TF) of metals which indicated that I. herbstii is suitable for phytostabilization of Ni (BCF>1 and TF

The reed bed system is one types of phytoremediation technology for removing pollutants from the environment. This technology provides an environmentally friendly approach to treating contamination with competitive cost, compared to the physico-chemical treatment. The design of reed bed system is highly important in order to achieve the highest pollutant removal efficiency. The design of reed bed system affects the natural oxygen transfer from the environment. The reed bed system was proven to have a good efficiency in removing Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), Total Dissolve Solid (TDS), Total Nitrogen (TN) and a number of bacteria. In addition to the oxygen transfer from the environment, the interaction among pollutant-plants-medium-microbes also plays a vital role in the removal of pollutant using the reed bed system. It was suggested that the future related research should accommodate the importance of several environmental conditions to the interaction between pollutant, plants, medium and microbes as well as the impact of those interactions on the pollutant removal efficiency.

This present research work was conducted to determine the phytotoxic effects on tropical native plants, Ludwigia octovalvis, in order to assess its application for phytoremediation of crude oil sludge in contaminated sand. For this purpose of study, L. octavalvis plants were planted in containers containing different proportion of spiked real crude oil sludge in sand (10%, 50%, and 100% (v/v)). Degradation of crude oil sludge by L. octovalvis was measured in terms of total petroleum hydrocarbons (TPH) and was compared with TPH degradation inside control crates without plants. The findings indicated that the average TPH removal after a prolonged 42-day exposure period was high. The degrees of TPH degradation were 67.0, 42.4 and 46.2% in sand spiked with real crude oil sludge at 10, 50 and 100% respectively, whereas the degradation was only 34.7, 29.1 and 20.5% for the unplanted containers at the same respective proportions of crude oil sludge in sand. These findings give evidence that L. octovalvis has the capability to degrade hydrocarbons in crude oil sludge.

Biosorption is fast, effective and low cost process. It takes place in a wide range of temperature and it can be used for almost all types of heavy metals. The aim of this study was to investigate the ability of locally collected green macro algae to remove copper, chromium and cadmium from synthetic wastewater. The fresh algae were converted into dry powder as biosorbent. In the investigations, 1 g of macro algae powder was exposed to synthetic waste water contaminated with 10 mg/L concentration of copper, chromium and cadmium in separate exposure for 2 hours. The best removal efficiency for copper, chromium and cadmium were 70%, 80% and 85%, respectively, from the initial concentration of 10 mg/L. While macro algae are abundantly available in marshlands of south Iraq, it can be preferably utilized as biosorbent to remove heavy metals from the industrial wastewater.

The present study focused on phytoremediation efficiency of water hyacinth for batik effluent treatment. Three operating factors were investigated such as retention times (0 to 28 days), batik effluent strength (20, 30 and 60%), and number of water hyacinth clumps (8, 10 and 12 clumps). The water hyacinth efficiencies was monitored through the measurement of dry weight, color, chemical oxygen demand (COD), total suspended solid (TSS), and pH. The highest efficiency of color and COD in the batik effluent treatment were achieved at day 7 with 83% (61 mg/L) and 89% (147 ADMI) removals, respectively. Both wastewater parameters were removed to below the Standard A for COD and Standard B for color. Meanwhile for TSS, the removal decreased as increased the batik effluent strength where the highest removal (92%) was achieved at day 28 with 8 number of plant clumps. The pH was observed in range of 6 to 7. The results indicated that water hyacinth would be the best option for the low cost batik effluent treatment.

Phytoremediation is one of the methods to remove various types of pollutants from water and soil using plants. Salvinia molesta, an aquatic plant, is chosen in this study to determine its ability to degrade diesel as the pollutant in synthetic wastewater with different diesel concentrations (0, 8,700, 17,400, and 26,100 mg/L) for 14 days. Total petroleum hydrocarbon (TPH) has been used as an indicator to represent diesel concentration variation in wastewater. Degradation of TPH was 85.1% for diesel concentration of 8,700 mg/L, compared with only 53.9% in the corresponding control without plant. While, acute toxicity on S. molesta exposed in diesel concentrations of 17,400 and 26,100 mg/L was observed and eventually had caused the plants to die after 14 days of exposure. Additionally, throughout the phytotoxicity test, the biomass of S. molesta was found to fluctuate confirming inhibition on plant to survive with diesel contaminated water compared with the corresponding control without contaminant. Based on the results obtained it is suggested to decrease diesel concentration less than 8,700 mg/L in future study due to insolubility of diesel in water and the toxicity to the aquatic plants

This study investigated the effect of co-culturing microalgae with a floc-forming bacterium. Of the six microalgae isolated from a biofloc sample, only Thalassiosira weissflogii, Chlamydomonas sp. and Chlorella vulgaris were propagated successfully in Conway medium. Hence, these species were selected for the experiment comparing microalgae axenic culture and co-culture with the floc-forming bacterium, Bacillus infantis. Results obtained showed that the co-culture had higher microalgae biomass compared to the axenic culture. A similar trend was also observed concerning the lipid content of the microalgae-bacterium co-cultures. The cell number of B. infantis co-cultured with T. weissflogii increased during the exponential stage until the sixth day, but the other microalgae species experienced a significant early reduction in cell density of the bacteria at the exponential stage. This study represents the first attempt at co-culturing microalgae with B. infantis, a floc-forming bacterium, and observed increased biomass growth and lipid accumulation compared to the axenic culture.

The coffee processing industry produces toxic and low biodegradable effluent, which can pollute water bodies. A pre-treatment study on coffee effluent using a dual-media biofilm reactor (DM-BR) containing sand and Hexafilter (HEX) was conducted alongside a control biofilm reactor (C-BR) containing sand media. The novelty of this study lies in the use of dual media in biofilm reactor (DM-BR) for real coffee effluent treatment, where these processes were used individually in previous studies. The performance of DM-BR and C-BR in treating coffee effluent were investigated at different hydraulic retention times (HRTs), 24, 48 and 72 h, and the degrading bacteria were identified. Both biofilm reactors were inoculated with a recycled paper mill-activated sludge and acclimatised for 97 days. The DM-BR displayed the highest removal of chemical oxygen demand (COD) and NH4+-N at 47% and 38%, respectively, within 48 h of HRT, whereas colour and tannin–lignin reached maximum average removal of 21% and 29%, respectively, at 24 h of HRT. The combination of sand and HEX media in a system showed COD and NH4+-N removal improvement at 48 h of HRT and encouraged a variety of bacterial species growth. Bacterial characterisation analysis revealed Proteobacteria to be dominant.

This research analyses the performance of bacteria-assisted phytoremediation of aluminium (Al)-contaminated soil using native Indonesian plants namely, Scirpus grossus and Thypa angustifolia. A range finding test (RFT) was carried out for 14 days to obtain the tolerable Al concentration for both plants. A total of 2% and 5% (v/v) of Vibrio alginolyticus were bioaugmented during the 28-day phytoremediation test to enhance the overall Al removal. Result of the RFT showed that both plants can tolerate up to 500 mg/kg Al concentration. The addition of V. alginolyticus to the reactors resulted in a significant increment of Al removal from the contaminated soil (p < 0.05). Such addition of V. alginolyticus increased the Al removal by up to 14.0% compared with that without-bacteria addition. The highest Al removal was obtained for S. grossus with 5% V. alginolyticus with an efficiency of 35.1% from 500 mg/kg initial concertation. T. angustifolia with 500 mg/kg initial concentration showed the highest removal of 26.2% by the addition of 5% V. alginolyticus. The increase of Al removal by the bioaugmentation of V. alginolyticus was due to the interaction in the plant's rhizosphere. Exudates of both plants provided a good environment for bacteria to live in the root area. Meanwhile, the bacteria increased the bioavailability of Al to be further extracted by plants. Certain mechanisms, such as rhizostabilisation, phytostimulation and phytoextraction, were considered to be the main processes that occurred during the treatment. S. grossus and T. angustifolia displayed promising ability to act as Al hyperaccumulators with bioaccumulation factor values up to 5.308 and 3.068, respectively. Development of the design of the ex-situ soil phytoremediation reactors is suggested as a future research direction because it can significantly enhance the current obtained finding.

In a slow sand filter, a biological layer consisting of alluvial mud and various types of microorganisms grows and attaches to the sand media and forms a matrix called schmutzdecke. Changes to several factors, including the quality of raw water, filtration speed, and the addition of media, affect the performance of the slow sand filter unit in producing treated water. Geotextiles can be equipped to improve the performance of a slow sand filter in removing pollutants. The selection of several factors that affect slow sand filter performance can be used as a starting point for the engineering system to determine the best pattern of performance behavior. This approach was carried out by looking at the dynamic behavior patterns of slow sand filter system performance in treating raw water. This research has not yet been conducted extensively. The dynamic behavior pattern approach to the performance of the slow sand filter unit was used to obtain the behavior model for the schmutzdecke layer on the filter. The system dynamic approach focused on treatment scenarios that can determine the behavior of the slow sand filter system. Several factors were assessed, including temperature, turbidity, nutrient concentration, algal concentration, bacteria and dissolved oxygen. Model simulation results show that the comparison of C: N: P values affected the performance of the schmutzdecke layer in removing total coli. The slow sand filter unit was capable of producing treated water with a total amount of coli equal to 0 on the C: N: P values of 85: 5.59: 1.25, respectively, and a 9 cm geotextile thickness.

A pot experiment was conducted to measure the phyto-tolerance and accumulation of heavy metals in petroleum oily sludge POS by Cajanus cajan (pigeon pea) on soils treated with five different concentrations (1%, 2%, 3%, 4%, and 5% w/w) of the POS. The response of the plant to oily sludge varied significantly from the untreated control and among the various treatments. The growth of C. cajan was slightly (but not significantly) influenced by the oily sludge in soil; growth of C. cajan at relatively lower concentrations of POS (1 to 3%) was greater than in the treatments with relatively higher concentrations POS (4 to 5%). A significant interaction was observed in the relative growth rates (RGRs) of C. cajan, which significantly increased in the treatments with relatively low POS (1 to 3%) and decrease significantly at higher POS concentrations. The heavy metal content of the plant roots as the POS concentrations were increase show that the concentration of all heavy metals in the roots increased accordingly. Cu showed the highest accumulation with an increase from 1.9 to 6.8 mg/kg followed by Pb, Zn, Ni, Mn, and Cr, which was the least-accumulated. Heavy metal analysis in C. cajan tissues indicated a considerable accumulation of the metals Pb, Zn, Ni, Mn, Cu, and Cr in the root and stem of the plant, with negligible metal concentrations detected in the plant leaves, suggesting a low translocation factor but indicating that C. cajan is resistant to heavy metals. As the search for more eco-friendly and sustainable remediating green plant continues, C. cajan shows great potential for reclaiming POS-contaminated soil due to the above properties including resistance to toxic heavy metals from oily sludge. These findings will provide solutions to polluted soils and their subsequent re-vegetation.

In this study, the capability of Vetiver zizaniodes in removing the pharmaceutical-based product, naproxen from wastewater was evaluated. The plant was exposed to naproxen at concentrations ranging from 50, 100, 300 and 500 mgL-1 for duration up to 56 days. Several wastewater parameters including pH, dissolved oxygen (DO, mgL-1) and oxygen-reduction potential (ORP, mV) were recorded during the experimental runs where pH and ORP exhibited significant different (p < 0.05). At the end of the exposure, 81.5%, 64.5% and 60.9% of naproxen were removed at 100, 300 and 500 mgL-1 concentration, respectively. The interaction between time, system and concentration showed significant naproxen removal (p < 0.05) from water and soil. Phytostimulation and phytostabilization played a major role for naproxen removal when there was an activity of the bacteria presence in the soil around the roots of the plants. Hence, V. zizaniodes is a potential plant in remediating pharmaceuticalcontaminated water and could act as a phytoremediator plant.

This study focused on the total petroleum hydrocarbon (TPH) degradation in phytoremediation of spiked diesel in sand. The diesel was added to the sand that was planted with terrestrial plants. Four selected terrestrial plants used were Paspalum vaginatum Sw, Paspalums crobiculatum L. varbispicatum Hack, Eragrotis atrovirens (Desf.) Trin. ex Steud and Cayratia trifolia (L.) Domin since all the plants could survive at a hydrocarbon petroleum contaminated site in Malaysia. The samplings were carried out on Day 0, 7, 14, 28, 42 and 72. The analysis of the TPH was conducted by extracting the spiked sand using ultrasonic extraction. The determination of the TPH concentration in the sand was performed using GC-FID. The degradation of TPH depends on the plant species and time of exposure. The highest percentage degradation by P. vaginatum, P. scrobiculatum, E. atrovirens and C. trifolia were 91.9, 74.0, 68.9 and 62.9%, respectively. In conclusion, the ability to degrade TPH by plants were P. vaginatum > P. scrobiculatum > E. atrovirens> C. trifolia.

Carbon from jatropha seed hull (JC) was prepared to study the adsorption of cadmium ions (Cd2+) from aqueous solutions under various experimental conditions. Batch equilibrium methods have been used to study the influences of the initial metal ion concentration (0.5–50 ppm), dosage (0.2–1 g), contact time (0–300 min), pH (2–7), and temperature (26–60 °C) on adsorption behavior. It has been found that the amount of cadmium adsorbed increases with the initial metal ion concentration, temperature, pH, contact time, and amount of adsorbent. A kinetic study proved that the mechanism of Cd2+ adsorption on JC followed a three steps process, confirmed by an intraparticle diffusion model: rapid adsorption of metal ions, a transition phase, and nearly flat plateau section. The experimental results also showed that the Cd2+ adsorption process followed pseudo-second-order kinetics. The Langmuir and Freundlich adsorption isotherm models were used to describe the experimental data, with the former exhibiting a better correlation coefficient than the latter (R2 = 0.999). The monolayer adsorption capacity of JC has been compared with the capacities of the other reported agriculturally-based adsorbents. It has been clearly demonstrated that this agricultural waste generated by the biofuel industry can be considered a potential low-cost adsorbent for the removal of Cd2+ from industrial effluents.

Heavy metals are among the most important sorts of contaminant in the environment. Several methods already used to clean up the environment from these kinds of contaminants, but most of them are costly and difficult to get optimum results. Currently, phytoremediation is an effective and affordable technological solution used to extract or remove inactive metals and metal pollutants from contaminated soil and water. This technology is environmental friendly and potentially cost effective. This paper aims to compile some information about heavy metals of arsenic, lead, and mercury (As, Pb, and Hg) sources, effects and their treatment. It also reviews deeply about phytoremediation technology, including the heavy metal uptake mechanisms and several research studies associated about the topics. Additionally, it describes several sources and the effects of As, Pb, and Hg on the environment, the advantages of this kind of technology for reducing them, and also heavy metal uptake mechanisms in phytoremediation technology as well as the factors affecting the uptake mechanisms. Some recommended plants which are commonly used in phytoremediation and their capability to reduce the contaminant are also reported.

This study was undertaken to identify the relevant bending points in ORP, pH, and DO profiles in ammonia removal through online monitoring. A novelty BAF system as newl application for drinking water treatment that equipped with ORP, pH, DO NH4 + and NO3 − sensors was used. Two types of polluted drinking water strength (low and high strength) with various NH4 + concentrations and aeration flow were treated at a fixed-time reaction of 24 h. Experiments were conducted at four track studies (TS) of TS1 (NH4 += 50 mg/L, aeration = 0.3 L/min), TS2 (NH4 + = 100 mg/L, aeration = 2.0 L/min), TS3 (NH4 += 100 mg/L, no aeration) and TS4 (NH4 += 10 mg/L, aeration = 0.1 L/min). The results showed that the removal of NH4 + was more than 95% for TS1, TS2, and TS4. From the online monitoring performances, DO elbow and ammonia valley appeared in ORP and pH profiles, respectively. Similarly, new positive plateaus were observed in DO, indicating that the nitrifiers stopped to consume the DO after NH4 + was completely removed. Hence, based on the bending points, the aeration system is possible to be automatically stopped just after DO elbow and ammonia valley appears in order to save the energy consumption and to shorten the time demands for the drinking water treatment process.