Treatment of polluted river water using potential bioflocculant produced by Klebsiella pneumonia UKD24.

Chemically enhanced primary treatment (CEPT) is a rapid wastewater treatment process involving treating wastewater with two chemical-aided processes, coagulation, and flocculation. In the present study, a natural extracellular polymeric substance flocculant (EPSBF) produced by Klebsiella pneumonia UKD24, a bacterium isolated from the sewage treatment plant, and a synthetic polyacrylamide anionic polymer flocculant (PAM) were evaluated to treat polluted river water. The synthetic PAM showed immediate turbidity reduction after agitation, while the EPSBF expressed a rapid decrease in optical density. After 20 min of the settling period, the EPSBF showed reduced rates of turbidity, optical density, and chemical oxygen demand at 74.14 ± 5.2%, 89.37 ± 0.76%, and 87.21 ± 0.73%, respectively, while PAM showed 67.08 ± 4%, 85.68 ± 2%, and 86.57 ± 2%, respectively. EPSBF treatment significantly improved the water quality parameters in terms of total dissolved solids, total suspended solids, conductivity, and oxidation-reduction potential than PAM treatment. However, the EPSBF has shown a more water-holding capacity and relatively weak flock formation, producing more sludge volume than PAM. Furthermore, though the sludge produced by the EPSBF treatment had a higher moisture content, it showed shorter capillary suction time (CST). In contrast, sludge formed in PAM treatment had lower moisture content, but it exhibited prolonged CST value indicating that PAM treatment sludge showed slow dewaterability.

Production of bioflocculant from Klebsiella pneumoniae: evaluation of fish waste extract as substrate and flocculation performance.

The bioflocculant producing bacterial strain - UKD24 was isolated from the domestic sewage treatment plant. The isolated strain was identified as Klebsiella pneumoniae by using 16S rRNA gene sequencing. The K. pneumoniae UKD24 showed remarkable flocculation rates when grown with the carbon sources namely glucose, sucrose and lactose, and many commercial nitrogen sources. Furthermore, the fish waste extract (FE) was used to enhance the productivity of the bioflocculant as a nitrogen supplement and it showed a significant level of flocculation rate similar to the commercial nitrogen sources. The Box-Behnken experiments were designed to predict the optimal conditions for bioflocculant production and it suggested that glucose - 3.247 g L-1, FE - 0.5 g L-1 and inoculum size - 1% are the suitable levels for bioflocculant production. The FTIR analysis of the bioflocculant showed the functional groups related to the polysaccharides and the EEM analysis showed the fluorescence components related to the proteins and humic acids. The biochemical composition of the bioflocculant was identified as polysaccharides (24.36 ± 1.5%) and protein (12.15 ± 0.2%). The tested optimum conditions of the bioflocculant to induce flocculation were tested in the kaolin wastewater and it showed that the optimum dosage of the flocculant was 5 mg L-1 and the pH range was broad as 5-10. The cation dependency tests revealed that the monovalent and divalent cations are highly suitable for flocculation while the trivalent cations showed moderate flocculation. The Cr(VI) removal efficiency of the bioflocculant showed that ∼35% of heavy metal is trapped into flocks during the flocculation.

Food waste valorization: Energy production using novel integrated systems.

Management of food waste (FW) is a global challenge due to increasing population and economic activities. Presently, landfill and incineration are the keyways of FW management, while economical and environmental sustainability have been an issue. Therefore, the biological processes have been investigated for resource and energy recovery from FW. However, these biological approaches have certain drawbacks and cannot be a complete solution for FW management. Therefore, this review aims to offer a detailed and complete analysis of current available technologies to achieve environmental and economical sustainability. In this context, zero solid waste discharge for resource and energy recovery has been put into view. Corresponding to which several innovative technologies using integrated biological methods for resource and energy recovery from FW have been elucidated.

Current challenges for shaping the sustainable and mold-free hygienic indoor environment in humid regions.

Indoor mold grows ubiquitously in humid areas and can affect occupants' health. To prevent indoor mold contamination, one of the key measures suggested by the World Health Organisation and United States Environmental Protection Agency is to maintain an indoor relative humidity (RH) level below 75% or at 30-60%, respectively. However, in tropical and subtropical areas, maintaining these suggested RH levels is equivalent to operating a 24-h air-conditioner (AC) or dehumidifier, which is energy-consuming. As a large part of building expense, the operation time of ACs has been regularly proposed to be cut down because of the requirement of building sustainability. This leads to a trade-off between sustainable building performance and indoor mold hygiene. To balance this trade-off, more sustainable alternatives, such as those that target physical environments (e.g. nutrient and temperature level) or apply new surface coating technologies to inhibit mold growth, have been launched. Despite these initiatives, indoor mold contamination remains an unresolved issue, mainly because these alternative measures only exhibit limited effectiveness or require extra effort. This review aims to summarize the currently adopted mold control measures and discuss their limitations as well as the direction for the future development of sustainable mold control strategies. SIGNIFICANCE AND IMPACT OF THE STUDY: People spend most of their time indoors and hence the presence of indoor mold contamination can compromise the occupants' health. With the wake of climate change which is expected to see an increase in RH and temperature, tropical and subtropical areas are even more prone to mold contamination than they used to be. This study may help facilitate the development of sustainable and effective mold control strategies in the indoor environment.

Control of lactic acid production during hydrolysis and acidogenesis of food waste.

Lactate accumulation occurs frequently during the hydrolysis and acidogenesis of food waste and produces an unfavorable substrate for anaerobic digestion. The objective of the present study was to reduce lactic acid production during the hydrolysis and acidogenesis of food waste in leachate bed reactor for establishment of the two-phase anaerobic digestion system. The results showed that the hydrolysis and acidogenesis of food waste in batch feeding mode underwent two consecutive stages, namely lactic acid fermentation and mixed acid fermentation. In the lactic acid fermentation stage, lactate constituted 74.4-96.8% of the total organic acids in the leachate. However in semi-continuous mode the content of lactate in the leachate could be reduced less than 0-2% for leach bed reactors operated at feeding loads of 50-150g/d although lactate accumulation occurred at a feeding load of 200g/d. Furthermore the organic acid shifted to acetate and butyrate, providing ideal substrates for anaerobic digestion.

Influence of fermented tannery solid waste on morphological, biochemical, yield and nutritional responses of tomato plants.

The non-tanned proteinaceous tannery solid waste animal fleshing (ANFL), containing high nutritive value, was hydrolyzed using bacteria Selenomonas ruminantium HM000123 through submerged (SmF) and solid-state (SSF) fermentation processes. In addition, the effects of ANFL fermentative hydrolysate on growth, yield and biochemical properties of tomato plants were investigated. The treatments included T1 (SmF-ANFL), T2 (SSF-ANFL), T3 (recommended dose of NPK fertilizers) and a control without any amendment. Hydrolysates of both SmF-ANFL and SSF-ANFL treatments increased the biomass and yield as evidenced by plant height, stem girth, number of leaves and fruit yield when compared with both NPK and control plants. In this 90-day study, significant (p ≤ 0.05) changes were observed in SSF-ANFL treated plants compared to the other treatments. Protein profile analyzed through SDS-PAGE indicates the expression of a high molecular weight protein (205 kDa) and other proteins in the leaves of the SSF-ANFL treated plants. Overall results revealed that SSF-ANFL can be successfully utilized as a fertilizer particularly for cultivating tomato plants.

Nutrient and enzymatic changes of hydrolysed tannery solid waste treated with epigeic earthworm Eudrilus eugeniae and phytotoxicity assessment on selected commercial crops.

Animal fleshing (ANFL) is the predominant proteinaceous solid waste generated during processing of leather and it is confronting disposal problems. The aim of this study was to assess the potential of epigeic earthworm Eudrilus eugeniae to utilize and transform the fermented ANFL in the solid state (SSF) and submerged state (SmF) into a value added product along a low residence period (25 days). A total of six treatment units containing different waste mixture compositions were established. Fifty healthy and non-clitellated earthworms were introduced in three different treatment containers: control, SSF, and SmF (+worm). Another set of treatment mixtures (control, SSF, SmF) was established without earthworms (-worm) to compare the results. The products were characterized for physico-chemical, enzymatic analysis and seedling growth parameters to compare the differences in the process with and without earthworms. The changes observed in the analytical parameters were in the following order: SSF > SmF > control mixtures (p < 0.05). The vermicompost showed a significant reduction in heavy metals, total organic carbon and an increase in total Kjeldhal nitrogen as compared to the product untreated by earthworms. The maximum enzymatic activities were observed after 21 days of vermicomposting. The relative seed germination of vermicompost extracts were in the order of tomato (Lycopersicon esculentum) > green gram (Vigna radiata) > cucumber (Cucumis sativus) > bottle gourd (Lagenaria siceraria (Mol.) Standl.) and showed no phytotoxicity effects. The results indicated that the combination of both ANFL hydrolysis through fermentation and vermicomposting is a good alternative to the management of this kind of waste.

Heterogeneous photocatalytic degradation of phenanthrene in surfactant solution containing TiO2 particles.

Photocatalytic degradation of phenanthrene (PHE) over TiO(2) in aqueous solution containing nonionic surfactant micelles was investigated. All photocatalytic experiments were conducted using a 253.7 nm mercury monochromatic ultraviolet lamp in a photocatalytic reactor. The surfactant micelles could provide a nonaqueous "cage" to result in a higher degradation rate of PHE than in an aqueous solution, but the higher Triton X-100 concentration (more than 2 g/L) lowered the degradation ratio of PHE because the additional surfactant micelles hindered the movement of micelles containing PHE so as to reduce their adsorption onto titania. Pseudo-second-order kinetics was observed for the photocatalytic degradation of PHE. Alkaline solution environment was beneficial to the photocatalytic degradation of PHE. PHE degradation could mainly be attributed to the formation of hydroxyl radicals as evident from the comparison of degradation efficiencies when O(2), H(2)O(2) and tert-butyl alcohol (TBA) were applied as oxidants or hydroxyl radical scavenger. Based on the GC/MS analysis of the intermediates, the possible pathways of the photocatalytic degradation of PHE were proposed.

Clinical results of early active mobilisation after flexor tendon repair.

Between 2005 and 2006, ten patients with flexor digitorum profundus zone II injuries were included. The mean age was 41 (19-84) years. One thumb, two index, four middle, one ring and two little fingers were injured. Repair method comprised four-strand core suture and 6-0 circumferential sutures. Post-operative rehabilitation included immediate active extension, progressive passive full flexion and active hold in dorsal block splint. Follow-up was four (three to seven) months. Grip strength, pinch strength, ROM was 90% (70%-90%), 90% (60%-110%) and 90% (80%-100%) of normal digit, respectively. Mayo wrist scores were five excellent, two good and three fair. All patients were satisfied. Compared with another group of ten patients with the same suture method and Kleinert splintage, grip strength, pinch strength and ROM were 50%, 40% and 40% of normal side, respectively. All differences between these two groups were statistically significant (p < 0.01) by paired samples T-test. There was no re-rupture.

Effects of pig manure compost and nonionic-surfactant Tween 80 on phenanthrene and pyrene removal from soil vegetated with Agropyron elongatum.

This paper evaluates the effects of pig manure compost (PMC) and Tween 80 on the removal of phenanthrene (PHE) and pyrene (PYR) from soil cultivated with Agropyron elongatum. Soils spiked with about 300 mg kg(-1) of PHE and PYR were individually amended with 0%, 2.5%, 5% and 7.5% (dry wt) of PMC or 0, 20 and 100 mg kg(-1) of Tween 80. Unplanted and sterile microcosms were prepared as the controls. PAH concentration, total organic matter (TOM), dissolved organic carbon (DOC), total heterotrophic and PAH degrading microbial populations in soil were quantified before and after 60d period. The results indicated that A. elongatum could significantly enhance PYR removal (from 46% to 61%) but had less impact on PHE removal (from 96% to 97%). Plant uptake of the PAHs was insignificant. Biodegradation was the key mechanism of PAH removals (<3% losses in the sterile control). Increase in PMC or Tween 80 levels increased the removal of PYR but not of PHE. Maximal PYR removal of 79% and 92% were observed in vegetated soil receiving 100 mg kg(-1) Tween 80 and 7.5% PMC, respectively. Enhanced PYR removal in soil receiving PMC could be explained by the elevated levels of DOC, TOM and microbial populations as suggested by Pearson correlation test. While the positive effect of Tween 80 on PYR removal could probably due to its capacities to enhance PYR bioavailability in soil. This paper suggests that the addition of either PMC or nonionic-surfactant Tween 80 could facilitate phytoremediation of PAH contaminated soil.

Phytochelatin systhesis and cadmium uptake of Brassica napus.

Soil contamination with cadmium (Cd) poses risk to human health. Metal hyperaccumulator plants play an important role in phytoextraction of heavy metals from such contaminated sites. Accumulation of Cd and its influence on the induction of phytochelatins in Brassica napus was investigated. Brassica napus plants were grown in nutrient culture with 1 and 5 microM Cd for 10 days. The biomass negatively correlates with Cd concentration in the nutrient solution and the reduction in dry weight was significantly higher for the root than the shoot. Cadmium accumulation positively correlates with the Cd concentration in the nutrient solution and the Cd accumulation in root is significantly higher than the shoot. High-performance liquid chromatography (HPLC) analysis revealed the induction of PC2, PC3 and PC4 in response to Cd in B. napus and their concentrations vary with the Cd level in the external solution. In 1 microM Cd treated plants; PC2 was the dominant thiol fraction in the root, followed by PC3 and PC4, whereas in the shoot, PC3 is the dominant species followed by PC4 and PC2. In 5 microM Cd treated plants, the concentration of both PC3 and PC4 are higher than that of PC2 in the roots. In the shoot, the concentration of PC3 and PC4 was higher than the PC2 irrespective of the quantity of Cd uptake, implying that the detoxification of Cd involves higher molecular weight thiol complexes in the shoot. Considering the high aboveground biomass and Cd accumulation in the shoot, B. napus can be a potential candidate for the phytoextraction of Cd.

Optimization of Fe2 +/solids content ratio for a novel sludge heavy metal bioleaching process.

A novel bioleaching process, preincubation bioleaching (PB) has been recently developed in our laboratory for decontamination of heavy-metal-laden sewage sludge by removing the toxic low molecular weight organic acids using an isolated degradative yeast species. The objective of the present study was to optimize Fe2+ /solids content ratio required for removing heavy metals from sewage sludge by using this novel process at high solids content. Results from the present study showed that regardless of the Fe2+ /solids content ratio iron oxidation and sludge acidification could be achieved within 2 days confirming the effectiveness of PB in reducing the inhibitory organic acids. When PB was conducted at an elevated solids content of 3%, Fe2 +/solids content ratio could be reduced to 0.75:1, 1:1 and 1.25:1 for solubilization of Zn, Cu and Cr respectively. Under this optimized bioleaching conditions, the following solubilization efficiencies were obtained after 8 days of bioleaching: 100% Zn, 96% Cu, 60% Cr with no reduction in nutrient contents. Hence, bioleaching at elevated solids contents represents a more economical way for decontamination of heavy-metal-laden sewage sludge while preserving its fertility values.

Co-cropping for phyto-separation of zinc and potassium from sewage sludge.

The use of sewage sludge as a fertilizer and soil amendment has resulted in high concentrations of heavy metals in the soil limiting its use. The present study was carried out to find the possibility of phyto-separating toxic and beneficial elements from the sludge using suitable plants. Of the five plants tested the hyperaccumulator Sedum alfredii H achieved the greatest removal of Zn, while shoots of Alocasia marorrhiza accumulated high content of K. Co-cropping these two plants on the sludge verified the previous observations on A. marorrhiza and the shoots of this plant could accumulate more than 120 g K kg(-1) dry matter in the median growth stage. Zn hyperaccumulated in Sedum's shoots to an extent more than 10 g kg(-1) dry matter; K concentrated five to ten times in the Alocasia's shoots which could be used as a good organic-K-fertilizer. Hence, the two elements were simultaneously phytoseparated and could be recycled. Furthermore, cultivation of plants in the sludge resulted in significant decreases in total Zn but kept the favorable agronomic characteristics of the sludge material, such as pH, organic matter content, and NPK concentrations and ameliorated its biological stability. These results suggest that simultaneous phyto-separation of toxic and beneficial elements from sewage sludge are possible by co-cropping using specific plants without the input of any chemicals.

Effect of synthetic surfactants on the solubilization and distribution of PAHs in water/soil-water systems.

The present study examined the effects of four surfactants, including three non-ionic surfactants (Tween 80, Triton X-100 and Brij 35) and an anionic surfactant SDS on the solubilization and distribution of phenanthrene (Phe) and pyrene (Pyr) in soil-water systems. All four surfactants could enhance the solubilization of Phe and Pyr in aqueous phase linearly when surfactant concentrations exceeded their respective critical micelle concentrations (CMC). Molar solubilization ratio (MSR) which indicated surfactant's solubilization capacity for Phe and Pyr, was highest for Tween 80 for both PAHs, and SDS had the lowest among the four surfactants, while Triton X-100 and Brij 35 had about the same MSR for both PAHs. Moreover, all the surfactants could provide a strong micelle partitioning phase for the more hydrophobic Pyr than Phe as revealed by their high micelle--aqueous phase partition coefficient, K(mc). Batch desorption studies also demonstrated that Tween 80 had the best capacity for the desorption of both Phe and Pyr in the soil-water systems, and followed by Triton X-100 and Brij 35, while SDS seems to have no positive effect on the desorption of PAHs probably due to its relatively high CMC value. Therefore, from the application standpoint, the results obtained in this study suggest that Tween 80 would be the most suitable candidate among the four surfactants in improving solubilization and desorption of PAHs in soil-water system, which are believed to be the prerequisites for successful bioremediation technology for PAH contaminated soil.

Growth of Agropyron elongatum in a simulated nickel contaminated soil with lime stabilization.

A greenhouse study was performed to evaluate the feasibility of using Agropyron elongatum and lime treatment for remediation of a simulated nickel (Ni) contaminated acidic soil. The acid soil was spiked with four levels of Ni, i.e., 0, 15, 50, and 100 mg Ni kg(-1) soil and the soil pH at each Ni level was adjusted to 4, 6 and 8 by liming with CaO. Addition of lime raised the soil pH and resulted in a decrease in concentrations of DTPA-extractable and water-soluble Ni in the soil, with a maximum reduction of 64 and 28 mg kg(-1), respectively at the highest level of Ni treatment as compared to the control without Ni treatment. In general, excessive Ni content in soil, especially at pH 4 inhibited the growth of Agropyron. Liming improved the growth condition and the highest dry weight yield of 12 g pot(-1) was obtained in soil spiked with 15 mg Ni kg(-1) at pH 6; and at the highest level of Ni, the dry weight yield increased from 0.48 to 5.96 g pot(-1) when the pH was increased from 4 to 6. However a further increase in pH to 8 did not improve plant yield because of the unavailability of nutrients at such a high pH. Nickel contents in plant were positively correlated to soil Ni contents at each respective pH level. Most of the Ni taken up by Agropyron was retained in the roots and the highest Ni uptake by plant was 3.9 mg pot(-1) in soil spiked with 100 mg Ni kg(-1) at pH 5.9, which was about 2.6% of total Ni added to the soil. This implies that Agropyron is not a hyperaccumulating species but is highly tolerant. Lime amendment together with the tolerant characteristic of Agropyron could provide a possible means to remediate Ni contaminated soils through phytostabilization.

[Adsorption of dissolved organic matter in soil and dissolved organic matter effect on the copper precipitation in high pH range].

Batch experiments were performed to study the dissolved organic matter (DOM) derived from green manure and pig manure sorption in acidic and calcareous soils and the effect of DOM derived from green manure and pig manure compost on the precipitation of copper at different pH in solution. The results showed that there was a significant net release of dissolved organic carbon (DOC) in soil (33.58 mg x L(-1) for calcareous soil and 17.17 mg x L(-1) for acidic soil) when a DOC-free solution was added. As the amount of added DOC increased, the release of DOC from soils decreased. This indicates that parts of the added DOC were sorbed by thesoil material and this effect was influenced by DOM's properties and soil properties. In this experiment the initial mass (IM) isotherm was used to describe the DOM sorption in soil which has been shown to be a useful tool for describing the sorption of DOC insoils because it takes into consideration the release of indigenous DOM from soil. As compared to green manure DOM, pig manure DOM had high m and Kd values, which indicated that it had a higher affinity with soil. As compared to that of green manure DOM, the m and Kd values are 0.4241, 2.946 in acidic soil and 0.2846, 1.58 in calcareous soil, respectively. What's more, the results also indicated that the acidic soil with higher Fe-oxide and Al-oxide content exhibited much higher DOC adsorption ability than calcareous soil rich in 2:1 minerals. In this experiment, green manure and pig manure compost DOM were selected to investigate the effects of DOM on the precipitation-dissolution behavior of copper at different pH. It can be found that DOM can inhibit the copper precipitation especially at high pH range because of the formation of DOM-Cu complex. From pH 6 to pH 10, as compared to the control treatment with no DOM added, the precipitation rate average decreased by 43.6% for the treatment with green manure DOM added and 22.65% for the treatment with pig manure compost DOM.

Speciation of heavy metals during co-composting of sewage sludge with lime.

During composting the humification of organic matter will have a significant effect on the physicochemical form of existence of heavy metals. Therefore the present study was conducted to investigate the effect of co-composting sewage sludge with lime on heavy metal speciation and the changes in DTPA extractable metals. Metal speciation was conducted to evaluate the redistribution of Cu, Mn, Ni, Pb and Zn in sewage sludge composted with lime. Sewage sludge was mixed with sawdust in 2:1 (w/w fresh weight) and then composted with lime at 0%, 0.63%, 1% or 1.63% (dry weight) for 100 days. The lime addition did not cause any changes in the different forms of Cu and Mn, but the composting process caused transformations of residual form of Cu and Mn into oxidizable and reducible form, respectively. For Ni, the reducible form was mainly transformed into residual form and lime addition decreased this transformation. Major transformation of different forms of Pb was not found, however the residual form of Pb increased with lime addition. The predominant residual form of Zn was mainly transformed into oxidizable form and the lime addition reduced this transformation. Addition of lime to sewage sludge during composting resulted in lower DTPA extractable metal contents. Therefore, lime is a suitable material to co-compost with sewage sludge to reduce the availability of heavy metals.

Transformation of organic matter during co-composting of pig manure with sawdust.

Co-composting of pig manure with sawdust was studied in order to characterize the organic transformation during the process, using both chemical and spectroscopic methods. Humic acids (HA) and fulvic acids (FA) were fractionated from immature and mature pig manure compost, and characterized. After 63 days of composting, the ratio of total organic carbon and soluble organic carbon decreased to a satisfactory low level and the solid and soluble C/N ratios decreased rapidly for the first 35 days before attaining a constant value, indicating compost maturity. Humification could be responsible for the increase in humic acid proportion during composting. The increase in the aromatic bonds after composting, as indicated by the reduction of C/H and C/O ratios of HA and FA, resulted in a more stabilized product. A substantial increase in high molecular weight compounds along with a small increase in low molecular weight compounds was found in mature compost. Moreover the HA also had more complex organic compounds at this stage. Fluorescence spectral analysis showed an increase in the maximum wavelength of HA associated with the contents of aromatic structures in solution. A decrease in relative absorbance of HA at 1160 cm(-1), 2950 cm(-1) and 2850 cm(-1) was seen in the FTIR spectra indicating the decomposition of complex organic constituents, into simpler ones. Increase in the aromatic compounds with higher stability could account for the relative increase in the absorbance of HA at 1650 cm(-1) and 1250 cm(-1) of the mature compost. The composition of FA was not much altered, indicating most of the degradation of organic matter occurred in HA. Data from organic carbon, C/N ratio, elemental analysis, E(4)/E(6) ratio, gel chromatography, fluorescence and FTIR spectra indicated an increase in polycondensed structures and the presence of more stable organic matter in the mature compost.

Combined effect of nonionic surfactant Tween 80 and DOM on the behaviors of PAHs in soil--water system.

Batch experiments were performed to examine the desorption behavior of phenanthrene and pyrene in soil-water system in the presence of nonionic surfactant Tween 80 and dissolved organic matter (DOM) derived from pig manure or pig manure compost. Addition of 150 mgl(-1) Tween 80 desorbed 5.8% and 2.1% of phenanthrene and pyrene from soil into aqueous phase, respectively, while the addition of both Tween 80 and DOM derived from pig manure compost and pig manure could further enhance the desorption of phenanthrene to 15.8% and 16.2%, respectively, and 6.4% and 10.9%, respectively, for pyrene. In addition, our finding also suggested that subsequent addition of Tween 80 into the soil-water system could further enhance PAHs desorption. The enhancement effect of the co-existence of Tween 80 and DOM was more than the additive effect of the Tween 80 and DOM individually. It is likely that the formation of DOM-surfactant complex in the soil-water system may be a possible reason to explain such desorption enhancement phenomenon. Therefore, it is anticipated that the coexistence of both Tween 80 and DOM derived from pig manure or pig manure compost in soil environment will enhance the bioavailability of PAHs as well as other hydrophobic organic contaminants (HOCs) by enhancing the desorption during remediation process.

Thermodynamic parameters for adsorption equilibrium of heavy metals and dyes from wastewater with low-cost adsorbents.

This note revisits the literature evaluating the thermodynamic parameters of adsorption equilibrium uptakes of heavy metals and dyes from water and wastewater streams using low-cost adsorbents derived from agricultural waste, industrial wastes, inorganic particulates, or some natural products. We highlighted the possible flaws in some adsorption studies when their thermodynamic parameters were assessed, since compensation effects during enthalpy and entropy evaluation were possibly overlooked.