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•High affinity and adsorption capacity of CHTs were in order of Zn2+>Ni2+>Cu2+.•Pseudo-second-order and Langmuir models well described kinetic and isotherm data.•The uptake process ...for Cu2+, Zn2+ or Ni2+ was spontaneous and endothermic.•The adsorbent could be used circularly 4 times efficiently.•Final removal of metal ions by reassembling hydrotalcites structures.
Although previously a variety of studies have proposed the removal of anions and organic matters from contaminated water by calcined hydroxides (CHTs), their role in uptaking potentially toxic metal ions from effluents had rarely been investigated. In the present study, simulated wastewater containing Cu2+, Zn2+ or Ni2+ was used to investigate the adsorption performance of CHTs. Langmuir and Freundlich isotherm models were employed to fit the equilibrium experiments, and it was found that the Langmuir model was more appropriate to describe the adsorption isotherm. The maximum adsorption amount was higher than some other adsorbents, specifically, being 6.583, 7.535 and 6.152mmol/g for Cu2+, Zn2+ or Ni2+ under the proposed conditions. For kinetic data, the pseudo-second-order kinetic model appeared to be the best-fitting model compared to the pseudo-first-order and Elovich models. Thermodynamic analysis revealed that Cu2+, Zn2+ or Ni2+ sorption on CHTs was spontaneous and endothermic. In the reusability study, the sorption capacity of the adsorbent did not vary remarkably in the initial four sorption/calcination cycles for Cu2+, Zn2+ or Ni2+ removal. By virtue of X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron dispersive X-ray analysis (EDX), it was speculated that the adsorption mechanism for Cu2+, Zn2+ or Ni2+ consisted of two steps: First, potentially toxic metal ions formed into hydroxide precipitations and adhered to the surfaces of adsorbents with high alkalinity. Second, the hydroxides participated in the process of adsorbents reconstructed the hydrotalcites structures through isomorphous substitution.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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•Biochemical wastewater from landfill leachate was applied directly to algal cultivation.•The excellent algal growth of 1.06 g/L was achieved from the 2nd cultivation.•Phosphorus ...replenishment into the wastewater doubled the yield of algae lipid.•Producing biodiesel through the full recycling chain could save 99% of the cost.
Heightened awareness of additional pretreatment for wastewater, has driven studies towards building a full wastewater-recycling chain wherein the wastewater pretreatment is performed by microalgae themselves. We applied biochemical wastewater from landfill leachate with added K2HPO4 (BWLL + P) directly to microalgal cultivation. The results showed that the pretreatment provided by the 1st cultivation reduced suspended solids by nearly half, greatly boosting microalgal growth, which thus yielded 1.06 g/L of dry mass and 87.06 mg/L·d of biomass productivity. From the 2nd to the 4th cultivation, lipid accumulation in BWLL + P was 1.12–1.27 times and 1.95–2.36 times higher than in BG11 and BWLL, respectively, mainly attributed to the comfortable environment engendered by the microalgal pretreatment and the organic carbon in the wastewater. Strikingly, the biodiesel production fed with BWLL + P could save 99% of the cost compared with in BG11. In combination, our pioneering full wastewater-recycling chain achieved microalgae’s self-reliant cultivation, with wastewater nourishment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Data on long-chain chlorinated paraffins (LCCPs) is extremely sparse, despite their use and emission are increasing with the phasing out of short-chain chlorinated paraffins (SCCPs). In this study, ...we analyzed chlorinated paraffins (CPs) in foodstuff samples (551 pooled samples, 93 items) divided into eight categories collected from Jinan, Shandong Province of China, by atmospheric-pressure chemical ionization quadrupole time-of-flight mass spectrometry (APCI-qToF-MS), to investigate the occurrence, contamination patterns and homologue patterns of LCCPs in foodstuff commonly consumed in traditional Chinese diet. LCCP intake through diet was estimated as well. LCCPs were detected in all pooled samples with geometric mean (GM) concentrations ranging from 1.8 to 21.9 ng/g wet weight (ng/g ww), contributing to 9-28% of the total CP mass in the studied foodstuff categories. The contamination patterns of LCCPs differed from SCCPs and medium-chain chlorinated paraffins (MCCPs), as reflected by the patterns of mass distribution, and by the lack of correlations between LCCP and S/MCCP concentrations in various foodstuff categories. The homologue profiles of LCCPs were extremely complex and diverse, with frequent detection of C30-36Cl2-15 very-long-chain chlorinated paraffin (vLCCP) congeners. The homologue profiles of eggs stood out for their high abundance of C18-22Cl9-13 LCCP congeners. LCCPs contributed 6.0-25.2% (8.9% for median estimation) to the estimated dietary intake (EDI) for total CPs through diet based on estimations using different percentiles of CP concentrations. The median estimate of dietary LCCP intake for adults in Jinan was 287.9 ng/kg_bw/day, reaching ~10- to 100-fold of that in Sweden and Canada. Considering the continuing production, use and emission of LCCPs, as well as the similar toxicity effects induced by LCCPs as SCCPs and MCCPs, attention should be paid to the health risk posed by LCCPs, or all CPs as a class of contaminants.
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•ΣLCCPs ranged 1.8 to 21.9 ng/g in samples of 8 food categories from Jinan.•The contamination patterns of LCCPs were different from those of SCCPs and MCCPs.•The homologue profiles of LCCPs in foodstuff were extremely complex and diverse.•LCCPs accounted for 9-28% of ΣCPs and 6.0-25.2% of the EDIΣCPs for adults in Jinan.•EDILCCPs in this study was 10- to 100-fold of that in Canada and Sweden.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Improving knowledge of the alga–bacterium interaction can promote the wastewater treatment. The untreated marine biopharmaceutical wastewater (containing native bacteria) was used directly for ...culturing microalgae. Unlike previous studies on specific bacteria in algal–bacterial co-culture systems, the effect of native bacteria in wastewater on microalgae growth was investigated in this study. The results showed that the coexistence of native bacteria greatly promoted the microalgae growth, ultimately producing biomass of 0.64 g/L and biomass productivity of 56.18 mg/L·d. Moreover, the lipid accumulation in the algae + bacteria group was 1.31 and 1.13 times higher than those of BG11 and pure algae, respectively, mainly attributed to the fact that bacteria provided a good environment for microalgae growth by using extracellular substances released from microalgae for their own growth, and providing micromolecules of organic matter and other required elements to microalgae. This study would lay the theoretical foundation for improving biopharmaceutical wastewater treatment.
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•Microalgae was introduced to real marine biopharmaceutical wastewater.•Alga–bacterium interaction improved the algal growth to 0.64 g/L of biomass.•The lipid accumulation of microalgae in co-culture was improved.•Pollutant removal was enhanced in co-culture due to the bacterial community.•Algal–bacterial interaction mechanism in real wastewater was revealed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In the commercial production of microalgae biodiesel, high culture cost and low lipid production yields are two major limitations. Finding cheap carbon sources and ways to promote lipid accumulation ...can achieve low-cost cultivation and efficient lipid production. The impact of NaCl on the growth and lipid accumulation in Scenedesmus quadricauda FACHB-1297 under xylose mixotrophic cultivation was explored in this study. The results showed that when NaCl concentration were 0.88–5.85 g/L, the biomass concentration and lipid content were 2.15–2.68 and 1.19–1.80 times higher than those in BG11 medium, respectively. Under the optimal NaCl concentration of 2.63 g/L, the highest lipid content (39.33%) was achieved, with the biomass concentration of 0.72 g/L, the total nitrogen removal efficiency of 39.00%, and the total phosphorus removal efficiency of nearly 100.00%, except for a higher total sugar content of 19.26% and total protein content of 5.38%. In short, these results indicated that 2.63 g/L NaCl treatment was an efficient way to promote the lipid accumulation of S. quadricauda FACHB-1297 using xylose in papermaking waste liquid to produce biofuel.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Copper can disturb the intracellular redox balance, induce oxidative stress, and subsequently cause irreversible damage, leading to a variety of diseases. In the present study, mouse primary ...hepatocytes were chosen to elucidate the in vitro oxidative damage of short-term copper exposure (10–200 μM) by single-cell analysis. We evaluated the toxicity of copper by reactive oxygen species (ROS), glutathione (GSH), and oxidative DNA damage at the single-cell level. Oxidative damage induced by copper was verified by the morphological changes, persistent elevations of excessive ROS and malondialdehyde (MDA), a decrease in GSH level, and the oxidative DNA damage. Furthermore, the average ROS generation, GSH consumption, and the indicators in DNA damage did not significantly change at relatively low concentrations (10 or 50 μM), but we can find the alterations of parameters in some single cells clearly. Emphasis on the analysis of single cells is conducive to gain a better understanding on the toxicity of copper. This study will also complement studies on the environmental risk assessment of copper pollution.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
For electroless nickel plating wastewater, a novel approach for the simultaneous removal of nickel and phosphorus on calcined Mg-Al-CO
3
hydroxides (CLDHs) is proposed. The dependence of the ...adsorption efficiency on several parameters, including initial ions' concentration, temperature, contact time and pH, has been investigated with batch experiments. The adsorption kinetics data of nickel and phosphorus could be well depicted by a pseudo-second-order model. Adsorption isotherms studies showed that the uptake of nickel and phosphorus on CLDHs followed Langmuir and Freundlich models, respectively, and that the maximum removal of nickel or phosphorus was up to 22.87 or 761.5 mg g
−1
. Thermodynamic analyses implied that the adsorption process of nickel or phosphorus on CLDHs was spontaneous and endothermic. Further, the possible mechanisms were explored in: low concentration solutions, CLDHs took part in reconstitution involving the isomorphous substitution of nickel at the magnesium sites in sheets and by the concomitant utilization of phosphorus by the generated superficial sheets; and in high concentration solutions, the CLDHs rebuilding hydrotalcite structures were influenced and formed mixed metal salts of phosphites, hydroxides, and hypophosphites, which were attributed to the presence of plentiful phosphorus and brought about the reduced uptake of nickel.
This picture shows the different adsorption mechanisms of CLDHs for electroless nickel plating wastewater with low and high ionic concentrations.
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IJS, KILJ, NUK, UL, UM, UPUK
Human serum albumin (HSA) is the most prominent protein in blood plasma with important physiological functions. Although copper is an essential metal for all organisms, the massive utilization of ...copper has led to concerns regarding its potential health impact. To better understand the potential toxicity and toxic mechanisms of Cu super(2+), it is of vital importance to characterize the interaction of Cu super(2+) with HSA. The effect of Cu super(2+) on the structure and function of HSA in vitro were investigated by biophysical methods including fluorescence techniques, circular dichroism (CD), time-resolved measurements, isothermal titration calorimetry (ITC), molecular simulations and esterase activity assay. Multi-spectroscopic measurements proved that Cu super(2+) quenched the intrinsic fluorescence of HSA in a dynamic process accompanied by the formation of complex and alteration of secondary structure. But the Cu super(2+) had minimal effect on the backbone and secondary structure of HSA at relatively low concentrations. The ITC results indicated Cu super(2+) interacted with HSA spontaneously through hydrophobic forces with approximately 1 thermodynamic identical binding sites at 298K. The esterase activity of HSA was inhibited obviously at the concentration of 810 super(-5)M. However, molecular simulation showed that Cu super(2+) mainly interacted with the amino acid residues Asp (451) by the electrostatic force. Thus, we speculated the interaction between Cu super(2+) and HSA might induce microenvironment of the active site (Arg 410). This study has provided a novel idea to explore the biological toxicity of Cu super(2+) at the molecular level.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
