Methylene blue(MB)is a versatile medicine with a long history of use in various medical applications,including dye,antiseptic,and treatment for methemoglobinemia.It has a role in vasoconstriction,methemoglobin reducti...Methylene blue(MB)is a versatile medicine with a long history of use in various medical applications,including dye,antiseptic,and treatment for methemoglobinemia.It has a role in vasoconstriction,methemoglobin reduction,inhibition of guanylate cyclase,and anti-inflammatory effects.We reviewed PubMed and Google Scholar literature for relevant studies on MB in intensive care unit(ICU).We created search criteria using a combination of free text words,including MB,critical care,intensive care,sepsis,surgery,pharmacokinetics,and pharmacodynamics.Relevant articles published in the English language were analyzed and incorporated.MB has been used in managing patients with refractory shock,including septic shock,vasoplegic shock,surgical patients,and some instances of drug-induced hypotension.In conclusion,MB in the ICU is a promising medication for sepsis and vasoplegic shock.Further research with randomized trials on its long-term safety in the ICU,time of initiation,dose,and duration is necessary.展开更多
To advance the precise regulation and high-value utilization of halloysite nanotubes(HNTs),this work systematically investigated five treatment strategies,including calcination,acid treatment,alkali treatment,acid tre...To advance the precise regulation and high-value utilization of halloysite nanotubes(HNTs),this work systematically investigated five treatment strategies,including calcination,acid treatment,alkali treatment,acid treatment of calcined HNTs,and alkali treatment of calcined HNTs,to modulate their structural and application properties.The structural characteristics,surface properties,and methylene blue(MB)adsorption capacity of HNTs under multiple treatments were systematically analyzed.Calcination at varying temperatures modified the crystal structure,morphology,and surface properties of HNTs,with higher calcination temperatures reducing their reactivity towards MB.Moderate acid treatment expanded the lumen and decreased the surface potential of HNTs,significantly enhancing MB adsorption capacity.In contrast,alkali treatment dispersed the multilayered walls of HNTs and raised surface potential,reducing MB affinity.Acid treatment of calcined HNTs effectively increased their specific surface areas by leaching most of Al while maintaining the tubular structure,thereby maximizing MB adsorption.Alkali treatment of calcined HNTs destroyed the tubular structure and resulted in poor MB adsorption.HNTs pre-calcined at 600℃ for 3 h and acid-treated at 60℃ for 8 h exhibited an optimal specific surface area of443 m^(2)·g^(-1)and an MB adsorption capacity of 190 mg·g^(-1).Kinetic and Arrhenius equation fittings indicated that chemical reactions control interactions of acids and alkalis with HNTs.This study provides a comprehensive comparison and analysis of five treatment methods,offering insights into regulating the structures and surface properties of HNTs by controlling the treatment condition,thereby laying a foundation for their efficient utilization in practical applications.展开更多
Exploring modification methods for enhancing the adsorption performance of biochar-based adsorbents for effective removal of methylene blue(MB),biochar-loaded CeO_(2)nanoparticles(Ce/BC)were synthesized by pomelo peel...Exploring modification methods for enhancing the adsorption performance of biochar-based adsorbents for effective removal of methylene blue(MB),biochar-loaded CeO_(2)nanoparticles(Ce/BC)were synthesized by pomelo peels through co-precipitation combined with the pyrolysis method.Ce/BC showed a higher specific surface area and disorder degree than that of BC.The 0.5Ce/BC(mass ratio of Ce(NO_(3))_(3)·6H_(2)O/BC=0.5/1)showed the best performance to adsorption of MB solution at different reaction conditions(MB concentration,Ce/BC composites dosage,and initial pH).Adsorption kinetics and equilibrium isotherms were well-described with a pseudo-first-order equation and Langmuir model,respectively.In addition,the maximum adsorption capacity of 0.5Ce/BC for MB was 105.68 mg·g^(-1)at 328 K.The strong adsorption was attributed to multi-interactions including pore filling,π-πinteractions,electrostatic interaction,and hydrogen bonding between the composites and MB.This work demonstrated that the modified pomelo peels biochar,as a green promising material with cost-effectiveness,exhibited a great potential for broad application prospectively to dyeing-contaminated wastewater treatment.展开更多
Adsorption coupled with photocatalytic degradation is proposed to fulfill the removal and thorough elimination of organic dyes.Herein,we report a facile hydrothermal synthesis of MIL-100(Fe)/GO photocatalysts.The adso...Adsorption coupled with photocatalytic degradation is proposed to fulfill the removal and thorough elimination of organic dyes.Herein,we report a facile hydrothermal synthesis of MIL-100(Fe)/GO photocatalysts.The adsorption and photocatalytic degradation process of methylene blue(MB)on MIL‐100(Fe)/GO composites were systematically studied from performance and kinetic perspectives.A possible adsorption‐photocatalytic degradation mechanism is proposed.The optimized 1M8G composite achieves 95%MB removal(60.8 mg/g)in 210 min and displays well recyclability over ten cycles.The obtained MB adsorption and degradation results are well fitted onto Langmuir isotherm and pseudo‐second order kinetic model.This study shed light on the design of MOFs based composites for water treatment.展开更多
In this work,the boron phosphide(BP)was synthesized and used for the adsorptive removal of methylene blue(MB)dye from aqueous solutions.To determine the optimum adsorption conditions,studies were performed by varying ...In this work,the boron phosphide(BP)was synthesized and used for the adsorptive removal of methylene blue(MB)dye from aqueous solutions.To determine the optimum adsorption conditions,studies were performed by varying parameters of temperature(298–328 K),pH(2–12),contact time(0–120 min),adsorbent dose(0.01–0.20 g/50 mL),and dye concentration(10–50 mg/L).Different isotherm and kinetic models were applied to the adsorption data.The linear correlations coefficient showed that the Langmuir isotherm best fits(R^(2)=0.9996).The maximum adsorption capacity of BP was obtained as 555.56 mg/g at 55℃and the removal rate reached up to 84.11%.Additionally,the pseudo-second-order kinetic model described the adsorption process best(R^(2)=0.9998).The thermodynamic studies represented that the adsorption occurred spontaneously(ΔG_(A)^(Θ)=−24.90 kJ/mol)and endothermically(ΔH_(A)^(Θ)=16.67 kJ/mol).The results showed that BP is an efficient adsorbent for removing cationic dyes from aqueous solutions.展开更多
A novel core-shell hydrogel bead was fabricated for effective removal of methylene blue dye from aqueous solutions.The core,made of sodium alginate-g-polyacrylamide and attapulgite nanofibers,was cross-linked by Calci...A novel core-shell hydrogel bead was fabricated for effective removal of methylene blue dye from aqueous solutions.The core,made of sodium alginate-g-polyacrylamide and attapulgite nanofibers,was cross-linked by Calcium ions(Ca^(2+)).The shell,composed of a chitosan/activated carbon mixture,was then coated onto the core.Fourier transform infrared spectroscopy confirmed the grafting polymerization of acrylamide onto sodium alginate.Scanning electron microscopy images showed the core-shell structure.The core exhibited a high water uptake ratio,facilitating the diffusion of methylene blue into the core.During the diffusion process,the methylene blue was first adsorbed by the shell and then further adsorbed by the core.Adsorption tests showed that the coreshell structure had a larger adsorption capacity than the core alone.The shell effectively enhanced the adsorption capacity to methylene blue compared to the single core.Methylene blue was adsorbed by activated carbon and chitosan in the shell,and the residual methylene blue diffused into the core and was further adsorbed.展开更多
Industrial effluents from textile, tannery or printing activities often have a significant pollutant load composed of dyes that are difficult to biodegrade. These dyes pose a threat to the environment. To overcome thi...Industrial effluents from textile, tannery or printing activities often have a significant pollutant load composed of dyes that are difficult to biodegrade. These dyes pose a threat to the environment. To overcome this problem, various processes have been developed to eliminate these dyes in wastewater before their release into nature. Conventional biological or physical processes most often prove to be ineffective and expensive. It is therefore necessary to resort to other processes such as advanced oxidation processes (POA). This work therefore focuses on the study of the influence of clay in the degradation of Methylene Blue by the photo-Fenton process which is one of the advanced oxidation processes (POA), with the source of irradiation, natural light. To do this, two clays from Côte d’Ivoire referenced AB and Aga were the subject of a physicochemical and mineralogical characterization. The results showed that Aga clay is composed of 75.43% quartz, 12.72% kaolinite, 8.75% illite and 3.12% goethite and AB clay consists of 61, 36% kaolinite, 28.6% quartz and 10.10% illite. Under natural light irradiation the optimal amounts of Fenton reagents (iron: 10 mg;H2O2: 0.1 mL) were determined. Finally, the addition of clay to the photo-Fenton process made it possible to improve the degradation of the pollutant (Methylene Blue). Indeed, the yield increased from 92% for the photo-Fenton process to 98.43% with the addition of AB clay and 98.13% for the addition of Aga clay. The results of the degradation kinetics clearly show that the degradation follows the pseudo-second order kinetics with correlation coefficients greater than 0.99.展开更多
AIM:To investigate whether activated carbon nanoparticles suspension(ACNS) or methylene blue(MB) can increase the detected number of lymph nodes in colorectal cancer.METHODS:Sixty-seven of 72 colorectal cancer patient...AIM:To investigate whether activated carbon nanoparticles suspension(ACNS) or methylene blue(MB) can increase the detected number of lymph nodes in colorectal cancer.METHODS:Sixty-seven of 72 colorectal cancer patients treated at our hospital fulfilled the inclusion criteria of the study which was conducted from December 2010 to February 2012.Seven patients refused to participate.Eventually,60 patients were included,and randomly assigned to three groups(20 in each group):ACNS group(group A),MB group(group B) and non-stained conventional surgical group(group C).In group A,patients received subserosal injection of 1 mL ACNS in a 4-quadrant region around the mass.In group B,the main artery of specimen was identified and isolated after the specimen was removed,and 2 mL MB was slowly injected into the isolated,stretched and fixed vessel.In group C,no ACNS and MB were injected.All the mesentery lymph nodes were isolated and removed systematically by visually inspecting and palpating the adipose tissue.RESULTS:No difference was observed among the three groups in age,gender,tumor location,tumor diameter,T-stage,degree of differentiation,postoperative complications and peritoneal drainage retention time.The total number of detected lymph nodes was 535,476 and 223 in the three groups,respectively.The mean number of detected lymph nodes per patient was significantly higher in group A than in group C(26.8 ± 8.4 vs 12.2 ± 3.2,P < 0.001).Similarly,there were significantly more lymph nodes detected in group B than in group C(23.8 ± 6.9 vs 12.2 ± 3.2,P < 0.001).However,there was no significant difference between group A and group B.There were 50,46 and 32 metastatic lymph nodes dissected in 13 patients of group A,10 patients of group B and 11 patients of group C,without significant differences among the three groups.Eleven of the 60 patients had insufficient number of detected lymph nodes(< 12).Only one patient with T 4a rectal cancer had 10 lymph nodes detected in group B,the other 10 patients were all from group C.Based on the different diameter categories,the number of detected lymph nodes in groups A and B was significantly higher than in group C.However,there was no statistically significant difference between group A and group B.The metastatic lymph nodes were not significant different among the three groups.Similarly,tumor location,T stage and tumor differentiation did not affect the staining results.Body mass index was a minor influencing factor in the two different staining methods.The stained lymph nodes can easily be identified from the mesenteric adipose tissues,and the staining time for lymph nodes was not significantly different compared with unstained group.None of the patients in groups A and B had drug-related complications.CONCLUSION:Both activated carbon nanoparticles suspension in vivo and methylene blue in vitro can be used as tracers to increase the detected number of lymph nodes in colorectal cancer.展开更多
A series of chitosan-g-poly （acrylic acid）/vermiculite hydrogel composites were synthesized and used as adsorbents for the investigation of the effect of process parameters such as vermiculite content, pH of dye sol...A series of chitosan-g-poly （acrylic acid）/vermiculite hydrogel composites were synthesized and used as adsorbents for the investigation of the effect of process parameters such as vermiculite content, pH of dye solution, contact time, initial concentration of dye solution, temperature, ionic strength and concentration of surfactant sodium dodecyl sulfate on the removal of Methylene Blue （MB） from aqueous solution. The results showed that the adsorption capacity for dye increased with increasing pH, contact time and initial dye concentration, but decreased with increasing temperature, ionic strength and sodium dodecyl sulfate concentration in the present of the surfactant. The adsorption kinetics of MB onto the hydrogel composite followed pseudo second-order kinetics and the adsorption equilibrium data obeyed Langmuir isotherm. By introducing 10 wt.% vermiculite into chitosan-g-poly （acrylic acid） polymeric network, the obtaining hydrogel composite showed the highest adsorption capacity for MB, and then could be regarded as a potential adsorbent for cationic dye removal in a wastewater treatment process.展开更多
Attapulgite（APT） has been frequently used for the adsorptive removal of dyes from aqueous solution owing to its unique one-dimensional nanoscale structure and low-cost, abundant,eco-friendly advantages. In this work...Attapulgite（APT） has been frequently used for the adsorptive removal of dyes from aqueous solution owing to its unique one-dimensional nanoscale structure and low-cost, abundant,eco-friendly advantages. In this work, APT was functionalized under mild hydrothermal condition using chloroacetic acid（CA） with ／COOH functional groups to improve its adsorption properties. The effect of hydrothermal modification on the microstructure and physicochemical features of APT was investigated by Fourier transform infrared spectroscopy, X-ray diffraction and Field-emission scanning electron microscopy analyses. The effects of hydrothermal reaction parameters on the adsorption properties of modified APT were intensively investigated. It was revealed that the rearrangement of crystal structure and the surface functionalization of APT with ／COOH groups cause the surprising increase of adsorption capability for Methylene Blue（MB）. The removal ratio of raw APT for MB is only 59.52%, while modified APT could almost completely remove MB in the 200 mg/L of MB solution with a removal ratio of 99.8%. The adsorption kinetics fitted pseudo second-order kinetic model, and the adsorption isotherm could be described with Langmuir isotherm model very well. The hydrogen-bonding interaction, electrostatic attraction and chemical association are the main driving force for the adsorption process.展开更多
The mixture of graphene oxide （GO） and dye molecules may provide some new applications due to unique electronic, optical, and structural properties. Methylene blue （MB）, a typ- ical anionic dye, can attach on GO v...The mixture of graphene oxide （GO） and dye molecules may provide some new applications due to unique electronic, optical, and structural properties. Methylene blue （MB）, a typ- ical anionic dye, can attach on GO via π-π stacking and electrostatic interaction, and the molecule removal process on GO has been observed. However, it remains unclear about the ultrafast carrier dynamics and the internal energy transfer pathways of the system which is composed of GO and MB. We have employed ultrafast optical pump-probe spectroscopy to investigate the excited dynamics of the GO-MB system dispersed in water by exciting the samples at 400 nm pump pulse. The pristine MB and GO dynamics are also analyzed in tandem for a direct comparison. Utilizing the global analysis to fit the measured signal via a sequential model, five lifetimes are acquired：（0.61±0.01） ps, （3.52±0.04） ps, （14.1±0.3） ps, （84±2） ps, and （3.66±0.08） ns. The ultrafast dynamics corresponding to these lifetimes was analyzed and the new relaxation processes were found in the GO-MB system, compared with the pristine MB. The results reveal that the functionalization of GO can alter the known decay pathways of MB via the energy transfer from GO to MB in system, the increased intermediate state, and the promoted energy transfer from triplet state MB to ground state oxygen molecules dissolved in aqueous sample.展开更多
An activation process for developing the surface and porous structure of palygorskite/carbon（PG/C） nanocomposite using ZnC l2 as activating agent was investigated. The obtained activated PG/C was characterized by X-...An activation process for developing the surface and porous structure of palygorskite/carbon（PG/C） nanocomposite using ZnC l2 as activating agent was investigated. The obtained activated PG/C was characterized by X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）, field-emission scanning electron microscopy（SEM）, and Brunauer-Emmett-Teller analysis（BET） techniques. The effects of activation conditions were examined,including activation temperature and impregnation ratio. With increased temperature and impregnation ratio, the collapse of the palygorskite crystal structure was found to accelerate and the carbon coated on the surface underwent further carbonization. XRD and SEM data confirmed that the palygorskite structure was destroyed and the carbon structure was developed during activation. The presence of the characteristic absorption peaks of C_C and C-H vibrations in the FTIR spectra suggested the occurrence of aromatization. The BET surface area improved by more than 11-fold（1201 m2/g for activated PG/C vs. 106 m2/g for PG/C） after activation, and the material appeared to be mainly microporous. The maximum adsorption capacity of methylene blue onto the activated PG/C reached 351 mg/g. The activated PG/C demonstrated better compressive strength than activated carbon without palygorskite clay.展开更多
Cerium-doped SiO2/TiO2 nanostructured fibers were fabricated by electrospinning technology. The prepared fibers were characterized by thermogravimetric analysis （TGA）, scanning electron microscopy （SEM）, X-ray dif...Cerium-doped SiO2/TiO2 nanostructured fibers were fabricated by electrospinning technology. The prepared fibers were characterized by thermogravimetric analysis （TGA）, scanning electron microscopy （SEM）, X-ray diffraction （XRD） and Fourier transform infrared spectroscopy （FT-IR）. Using the fibers as catalysts, photoeatalytic degradation of Methylene Blue （MB） aqueous solution was carded out under simulated sunlight. The 0.2% Ce doping proved to be the optimal concentration for the doping of TiO2/SiO2, compared to other Ce-doped molar concentrations. The 0.2% Ce-doped SiOdTiO2 fibers exhibited higher photocatalytic activity than industrial Degussa P25 and the samples doped with only Ce or SIO2. The reasons for improving the photocatalytic activity were also discussed. Several operational parameters were studied, which showed that the photocatalytic efficiency of MB was influenced by parameters such as the initial dye concentration, the initial pH, inorganic anions, and so on. In addition, the influences of an electron acceptor and a radical scavenger suggested that OH was the dominant photooxidant during the photocatalytic process. The reuse evaluation of the fibers indicated that their photocatalytic activity had good stability.展开更多
Rare earth ions La3＋ and Eu3＋ co-doped TiO2 photocatalyst （La-Eu/TiO2） was prepared by sol-gel method, and characterized by various techniques such as X-ray diffraction （XRD）, specific surface area and porosity ...Rare earth ions La3＋ and Eu3＋ co-doped TiO2 photocatalyst （La-Eu/TiO2） was prepared by sol-gel method, and characterized by various techniques such as X-ray diffraction （XRD）, specific surface area and porosity （BET and BJH）, scanning electron microscopy （SEM）, high resolution transmission electron microscopy （HRTEM）, UV-vis diffuse reflectance spectroscopy （DRS） and X-ray photoelectron spectroscopy （XPS）. The photocatalytic activity of the La-Eu/TiO2 was evaluated by the degradation of methylene blue （MB） under UV light irradiation. The catalyst had a relatively uniform particle diameter distribution in the range of 40–60 nm. When calcining at 600℃, the XRD patterns of La-Eu/TiO2 indicated the anatase phase, while the XPS patterns showed the Ti4＋, La3＋ and Eu3＋ ions existence. The DRS spectra showed red shift in the band-gap transition. The experimental results of MB degradation demonstrated that the photocatalytic activity of La-Eu/TiO2 was significantly enhanced due to better separation of photogenerated electron-hole pairs.展开更多
Polyaniline （PAn） sensitized nanocrystalline TiO2 composites （TiO2/PAn） were successfully prepared and used as an efficient photocatalyst for the degradation of dye methylene blue （MB）. The results showed that P...Polyaniline （PAn） sensitized nanocrystalline TiO2 composites （TiO2/PAn） were successfully prepared and used as an efficient photocatalyst for the degradation of dye methylene blue （MB）. The results showed that PAn was able to sensitize TiO2 efficiently and the composite photocatalyst could be activated by absorbing both the ultraviolet and visible light （λ： 190 ～ 800 nm）, whereas pure TiO2 absorbed ultraviolet light only （λ 〈 380 nm）. Under the irradiation of natural light, MB could be degraded more efficiently on the TiO2/PAn composites than on the TiO2 Furthermore, it could be easily separated from the solution by simple sedimentation.展开更多
Tea (Camellia sinensis L.) seed shells, the main byproduct of the manufacture of tea seed oil, were used as precursors for the preparation of tea activated carbon (TAC) in the present study. A high yield (44.1%) of TA...Tea (Camellia sinensis L.) seed shells, the main byproduct of the manufacture of tea seed oil, were used as precursors for the preparation of tea activated carbon (TAC) in the present study. A high yield (44.1%) of TAC was obtained from tea seed shells via a one-step chemical method using ZnCl2 as an agent. The Brunauer-Emmett-Teller (BET) surface area and the total pore volumes of the obtained TAC were found to be 1 530.67 mg2/g and 0.7826 cm3/g, respectively. The equilibrium adsorption results were complied with Langmuir isotherm model and its maximum monolayer adsorption capacity was 324.7 mg/g for methylene blue. Adsorption kinetics studies indicated that the pseudosecond-order model yielded the best fit for the kinetic data. An intraparticle diffusion model suggested that the intraparticle diffusion was not the only rate-controlling step. Thermodynamics studies revealed the spontaneous and exothermic nature of the sorption process. These results indicate that tea seed shells could be utilized as a renewable resource to develop activated carbon which is a potential adsorbent for methylene blue.展开更多
In this study,an alternative precursor for production of activated carbon was introduced using dragon fruit(Hylocereus costaricensis)peel(DFP).Moreover,KOH was used as a chemical activator in the thermal carbonization...In this study,an alternative precursor for production of activated carbon was introduced using dragon fruit(Hylocereus costaricensis)peel(DFP).Moreover,KOH was used as a chemical activator in the thermal carbonization process to convert DFP into activated carbon(DFPAC).In order to accomplish this research,several approaches were employed to examine the elemental composition,surface properties,amorphous and crystalline nature,essential active group,and surface morphology of the DFPAC.The BrunauerEmmettTeller test demonstrated a mesoporous structure of the DFPAC has a high surface area of 756.3 m2g 1.The cationic dye Methylene Blue(MB)was used as a probe to assess the efficiency of DFPAC towards the removal of MB dye from aqueous solution.The effects of adsorption input factors(e.g.DFPAC dose(A:0.040.12 g L 1),pH(B:310),and temperature(C:3050℃))were investigated and optimized using statistical analysis(i.e.BoxBehnken design(BBD)).The adsorption kinetic model can be best categorized as the pseudofirst order(PFO).Whereas,the adsorption isotherm model can be best described by Langmuir model,with maximum adsorption capacity of DFPAC for MB dye was 195.2 mg g 1 at 50℃.The adsorption mechanism of MB by DFPAC surface was attributed to the electrostatic interaction,pp interaction,and Hbonding.Finally,the results support the ability of DFP to be a promising precursor for production of highly porous activated carbon suitable for removal of cationic dyes(e.g.MB).展开更多
The methylene blue（MB）removal abilities of raw activated carbon and iron/cerium modified raw activated carbon（Fe–Ce-AC）by adsorption were researched and compared.The characteristics of Fe–Ce-AC were examined by ...The methylene blue（MB）removal abilities of raw activated carbon and iron/cerium modified raw activated carbon（Fe–Ce-AC）by adsorption were researched and compared.The characteristics of Fe–Ce-AC were examined by N2adsorption,zeta potential measurement,FTIR,Raman,XRD,XPS,SEM and EDS.After modification,the following phenomena occurred：The BET surface area,average pore diameter and total pore volume decreased;the degree of graphitization also decreased.Moreover,the presence of Fe3O4led to Fe–Ce-AC having magnetic properties,which makes it easy to separate from dye wastewater in an external magnetic field and subsequently recycle.In addition,the equilibrium isotherms and kinetics of MB adsorption on raw activated carbon and Fe–Ce-AC were systematically examined.The equilibrium adsorption data indicated that the adsorption behavior followed the Langmuir isotherm,and the pseudo-second-order model matched the kinetic data well.Compared with raw activated carbon,the maximum monolayer adsorption capacity of Fe–Ce-AC increased by27.31%.According to the experimental results,Fe–Ce-AC can be used as an effective adsorbent for the removal of MB from dye wastewater.展开更多
The tea wastages could remove methylene blue（MB） as a cationic dye from waste water corresponding to second-order kinetic model.Thermodynamic studies showed that adsorption equilibrium constant（KL） and maximum ads...The tea wastages could remove methylene blue（MB） as a cationic dye from waste water corresponding to second-order kinetic model.Thermodynamic studies showed that adsorption equilibrium constant（KL） and maximum adsorption capacities（Q（max）） were increased with increasing temperature.The removal efficiency of MB for Co 0.01 mmol/L at optimum conditions was about 85%. The maximum uptake capacity（Q（max）） of methylene blue in a batch reactor was 0.328,0.542 and 0.659 mmol/g at 15,25 and 40℃, respectively.The enthalpy change（ΔH） and entropy change（ΔS） were 11.356 kJ/mol and 20.563 J/（mol K）,respectively.展开更多
The adsorption kinetics of methylene blue from aqueous solutions on purified palygorskite was investigated. The kinetics data related to the adsorption of methylene blue from aqueous solutions are in good agreement wi...The adsorption kinetics of methylene blue from aqueous solutions on purified palygorskite was investigated. The kinetics data related to the adsorption of methylene blue from aqueous solutions are in good agreement with the pseudo-second order equation in ranges of initial concentration of 120-210 mg/L, oscillation speed of 100-200 r/min and temperature of 298-328K. The experimental results show that methylene blue is only adsorbed onto the external surface of purified palygorskite, and the apparent adsorption activation energy is 13.92 kJ/mol. The relatively low apparent adsorption activation energy suggests that the adsorption of methylene blue involves in not only a chemical, but also a physical adsorption process, and it is controlled by the combination of chemical adsorption and fiquid-film diffusion.展开更多
文摘Methylene blue(MB)is a versatile medicine with a long history of use in various medical applications,including dye,antiseptic,and treatment for methemoglobinemia.It has a role in vasoconstriction,methemoglobin reduction,inhibition of guanylate cyclase,and anti-inflammatory effects.We reviewed PubMed and Google Scholar literature for relevant studies on MB in intensive care unit(ICU).We created search criteria using a combination of free text words,including MB,critical care,intensive care,sepsis,surgery,pharmacokinetics,and pharmacodynamics.Relevant articles published in the English language were analyzed and incorporated.MB has been used in managing patients with refractory shock,including septic shock,vasoplegic shock,surgical patients,and some instances of drug-induced hypotension.In conclusion,MB in the ICU is a promising medication for sepsis and vasoplegic shock.Further research with randomized trials on its long-term safety in the ICU,time of initiation,dose,and duration is necessary.
基金Tural Science Foundation of China(No.52274255)the Young Scientists Fund of the National Natural ScienceFoundation of China(No.52404276)+3 种基金Fundamental Re-search Funds for the Central Universities,China(Nos.N2301003,N2201008,N2201004,and N2301025)Liaon-ingRevitalizationTalentsProgram,China(No.XLYC2202028)Postdoctoral Foundation of NortheasternUniversity,Young Elite Scientists Sponsorship Program byChina Association for Science and Technology(No.2022QNRC001)and China Postdoctoral Science Founda-tion(No.2022M720025)。
文摘To advance the precise regulation and high-value utilization of halloysite nanotubes(HNTs),this work systematically investigated five treatment strategies,including calcination,acid treatment,alkali treatment,acid treatment of calcined HNTs,and alkali treatment of calcined HNTs,to modulate their structural and application properties.The structural characteristics,surface properties,and methylene blue(MB)adsorption capacity of HNTs under multiple treatments were systematically analyzed.Calcination at varying temperatures modified the crystal structure,morphology,and surface properties of HNTs,with higher calcination temperatures reducing their reactivity towards MB.Moderate acid treatment expanded the lumen and decreased the surface potential of HNTs,significantly enhancing MB adsorption capacity.In contrast,alkali treatment dispersed the multilayered walls of HNTs and raised surface potential,reducing MB affinity.Acid treatment of calcined HNTs effectively increased their specific surface areas by leaching most of Al while maintaining the tubular structure,thereby maximizing MB adsorption.Alkali treatment of calcined HNTs destroyed the tubular structure and resulted in poor MB adsorption.HNTs pre-calcined at 600℃ for 3 h and acid-treated at 60℃ for 8 h exhibited an optimal specific surface area of443 m^(2)·g^(-1)and an MB adsorption capacity of 190 mg·g^(-1).Kinetic and Arrhenius equation fittings indicated that chemical reactions control interactions of acids and alkalis with HNTs.This study provides a comprehensive comparison and analysis of five treatment methods,offering insights into regulating the structures and surface properties of HNTs by controlling the treatment condition,thereby laying a foundation for their efficient utilization in practical applications.
基金supported by Basic scientific research business expense project of colleges and universities directly under Inner Mongolia(2024QNJS127 and 2023QNJS131)Science and Technology Plan Program of Inner Mongolia Autonomous Region(2023YFDZ0031)the Inner Mongolia Natural Science Foundation(2024QN02011).
文摘Exploring modification methods for enhancing the adsorption performance of biochar-based adsorbents for effective removal of methylene blue(MB),biochar-loaded CeO_(2)nanoparticles(Ce/BC)were synthesized by pomelo peels through co-precipitation combined with the pyrolysis method.Ce/BC showed a higher specific surface area and disorder degree than that of BC.The 0.5Ce/BC(mass ratio of Ce(NO_(3))_(3)·6H_(2)O/BC=0.5/1)showed the best performance to adsorption of MB solution at different reaction conditions(MB concentration,Ce/BC composites dosage,and initial pH).Adsorption kinetics and equilibrium isotherms were well-described with a pseudo-first-order equation and Langmuir model,respectively.In addition,the maximum adsorption capacity of 0.5Ce/BC for MB was 105.68 mg·g^(-1)at 328 K.The strong adsorption was attributed to multi-interactions including pore filling,π-πinteractions,electrostatic interaction,and hydrogen bonding between the composites and MB.This work demonstrated that the modified pomelo peels biochar,as a green promising material with cost-effectiveness,exhibited a great potential for broad application prospectively to dyeing-contaminated wastewater treatment.
基金National Natural Science Foundation of China(Grant No.21902001,22179001)Distinguished Young Research Project of Anhui Higher Education Institution(Grant No.2022AH020007)+1 种基金University Synergy Innovation Program of Anhui Province(Grant No.GXXT-2023-009)Higher Education Natural Science Foundation of Anhui Province(Grant No.2023AH050114).
文摘Adsorption coupled with photocatalytic degradation is proposed to fulfill the removal and thorough elimination of organic dyes.Herein,we report a facile hydrothermal synthesis of MIL-100(Fe)/GO photocatalysts.The adsorption and photocatalytic degradation process of methylene blue(MB)on MIL‐100(Fe)/GO composites were systematically studied from performance and kinetic perspectives.A possible adsorption‐photocatalytic degradation mechanism is proposed.The optimized 1M8G composite achieves 95%MB removal(60.8 mg/g)in 210 min and displays well recyclability over ten cycles.The obtained MB adsorption and degradation results are well fitted onto Langmuir isotherm and pseudo‐second order kinetic model.This study shed light on the design of MOFs based composites for water treatment.
文摘In this work,the boron phosphide(BP)was synthesized and used for the adsorptive removal of methylene blue(MB)dye from aqueous solutions.To determine the optimum adsorption conditions,studies were performed by varying parameters of temperature(298–328 K),pH(2–12),contact time(0–120 min),adsorbent dose(0.01–0.20 g/50 mL),and dye concentration(10–50 mg/L).Different isotherm and kinetic models were applied to the adsorption data.The linear correlations coefficient showed that the Langmuir isotherm best fits(R^(2)=0.9996).The maximum adsorption capacity of BP was obtained as 555.56 mg/g at 55℃and the removal rate reached up to 84.11%.Additionally,the pseudo-second-order kinetic model described the adsorption process best(R^(2)=0.9998).The thermodynamic studies represented that the adsorption occurred spontaneously(ΔG_(A)^(Θ)=−24.90 kJ/mol)and endothermically(ΔH_(A)^(Θ)=16.67 kJ/mol).The results showed that BP is an efficient adsorbent for removing cationic dyes from aqueous solutions.
文摘A novel core-shell hydrogel bead was fabricated for effective removal of methylene blue dye from aqueous solutions.The core,made of sodium alginate-g-polyacrylamide and attapulgite nanofibers,was cross-linked by Calcium ions(Ca^(2+)).The shell,composed of a chitosan/activated carbon mixture,was then coated onto the core.Fourier transform infrared spectroscopy confirmed the grafting polymerization of acrylamide onto sodium alginate.Scanning electron microscopy images showed the core-shell structure.The core exhibited a high water uptake ratio,facilitating the diffusion of methylene blue into the core.During the diffusion process,the methylene blue was first adsorbed by the shell and then further adsorbed by the core.Adsorption tests showed that the coreshell structure had a larger adsorption capacity than the core alone.The shell effectively enhanced the adsorption capacity to methylene blue compared to the single core.Methylene blue was adsorbed by activated carbon and chitosan in the shell,and the residual methylene blue diffused into the core and was further adsorbed.
文摘Industrial effluents from textile, tannery or printing activities often have a significant pollutant load composed of dyes that are difficult to biodegrade. These dyes pose a threat to the environment. To overcome this problem, various processes have been developed to eliminate these dyes in wastewater before their release into nature. Conventional biological or physical processes most often prove to be ineffective and expensive. It is therefore necessary to resort to other processes such as advanced oxidation processes (POA). This work therefore focuses on the study of the influence of clay in the degradation of Methylene Blue by the photo-Fenton process which is one of the advanced oxidation processes (POA), with the source of irradiation, natural light. To do this, two clays from Côte d’Ivoire referenced AB and Aga were the subject of a physicochemical and mineralogical characterization. The results showed that Aga clay is composed of 75.43% quartz, 12.72% kaolinite, 8.75% illite and 3.12% goethite and AB clay consists of 61, 36% kaolinite, 28.6% quartz and 10.10% illite. Under natural light irradiation the optimal amounts of Fenton reagents (iron: 10 mg;H2O2: 0.1 mL) were determined. Finally, the addition of clay to the photo-Fenton process made it possible to improve the degradation of the pollutant (Methylene Blue). Indeed, the yield increased from 92% for the photo-Fenton process to 98.43% with the addition of AB clay and 98.13% for the addition of Aga clay. The results of the degradation kinetics clearly show that the degradation follows the pseudo-second order kinetics with correlation coefficients greater than 0.99.
文摘AIM:To investigate whether activated carbon nanoparticles suspension(ACNS) or methylene blue(MB) can increase the detected number of lymph nodes in colorectal cancer.METHODS:Sixty-seven of 72 colorectal cancer patients treated at our hospital fulfilled the inclusion criteria of the study which was conducted from December 2010 to February 2012.Seven patients refused to participate.Eventually,60 patients were included,and randomly assigned to three groups(20 in each group):ACNS group(group A),MB group(group B) and non-stained conventional surgical group(group C).In group A,patients received subserosal injection of 1 mL ACNS in a 4-quadrant region around the mass.In group B,the main artery of specimen was identified and isolated after the specimen was removed,and 2 mL MB was slowly injected into the isolated,stretched and fixed vessel.In group C,no ACNS and MB were injected.All the mesentery lymph nodes were isolated and removed systematically by visually inspecting and palpating the adipose tissue.RESULTS:No difference was observed among the three groups in age,gender,tumor location,tumor diameter,T-stage,degree of differentiation,postoperative complications and peritoneal drainage retention time.The total number of detected lymph nodes was 535,476 and 223 in the three groups,respectively.The mean number of detected lymph nodes per patient was significantly higher in group A than in group C(26.8 ± 8.4 vs 12.2 ± 3.2,P < 0.001).Similarly,there were significantly more lymph nodes detected in group B than in group C(23.8 ± 6.9 vs 12.2 ± 3.2,P < 0.001).However,there was no significant difference between group A and group B.There were 50,46 and 32 metastatic lymph nodes dissected in 13 patients of group A,10 patients of group B and 11 patients of group C,without significant differences among the three groups.Eleven of the 60 patients had insufficient number of detected lymph nodes(< 12).Only one patient with T 4a rectal cancer had 10 lymph nodes detected in group B,the other 10 patients were all from group C.Based on the different diameter categories,the number of detected lymph nodes in groups A and B was significantly higher than in group C.However,there was no statistically significant difference between group A and group B.The metastatic lymph nodes were not significant different among the three groups.Similarly,tumor location,T stage and tumor differentiation did not affect the staining results.Body mass index was a minor influencing factor in the two different staining methods.The stained lymph nodes can easily be identified from the mesenteric adipose tissues,and the staining time for lymph nodes was not significantly different compared with unstained group.None of the patients in groups A and B had drug-related complications.CONCLUSION:Both activated carbon nanoparticles suspension in vivo and methylene blue in vitro can be used as tracers to increase the detected number of lymph nodes in colorectal cancer.
基金supported by the National Natural Science Foundation of China (No.20877077)the Project of Jiangsu Provincial Science and Technology Office (No.BE2008087)
文摘A series of chitosan-g-poly （acrylic acid）/vermiculite hydrogel composites were synthesized and used as adsorbents for the investigation of the effect of process parameters such as vermiculite content, pH of dye solution, contact time, initial concentration of dye solution, temperature, ionic strength and concentration of surfactant sodium dodecyl sulfate on the removal of Methylene Blue （MB） from aqueous solution. The results showed that the adsorption capacity for dye increased with increasing pH, contact time and initial dye concentration, but decreased with increasing temperature, ionic strength and sodium dodecyl sulfate concentration in the present of the surfactant. The adsorption kinetics of MB onto the hydrogel composite followed pseudo second-order kinetics and the adsorption equilibrium data obeyed Langmuir isotherm. By introducing 10 wt.% vermiculite into chitosan-g-poly （acrylic acid） polymeric network, the obtaining hydrogel composite showed the highest adsorption capacity for MB, and then could be regarded as a potential adsorbent for cationic dye removal in a wastewater treatment process.
基金supported by the Hi-Tech research and Development Program (863) of China (No. 2013AA032003)the West Light Foundation of the Chinese Academy of Sciences (the Science Development Talent Teach words [2012] No. 179)
文摘Attapulgite（APT） has been frequently used for the adsorptive removal of dyes from aqueous solution owing to its unique one-dimensional nanoscale structure and low-cost, abundant,eco-friendly advantages. In this work, APT was functionalized under mild hydrothermal condition using chloroacetic acid（CA） with ／COOH functional groups to improve its adsorption properties. The effect of hydrothermal modification on the microstructure and physicochemical features of APT was investigated by Fourier transform infrared spectroscopy, X-ray diffraction and Field-emission scanning electron microscopy analyses. The effects of hydrothermal reaction parameters on the adsorption properties of modified APT were intensively investigated. It was revealed that the rearrangement of crystal structure and the surface functionalization of APT with ／COOH groups cause the surprising increase of adsorption capability for Methylene Blue（MB）. The removal ratio of raw APT for MB is only 59.52%, while modified APT could almost completely remove MB in the 200 mg/L of MB solution with a removal ratio of 99.8%. The adsorption kinetics fitted pseudo second-order kinetic model, and the adsorption isotherm could be described with Langmuir isotherm model very well. The hydrogen-bonding interaction, electrostatic attraction and chemical association are the main driving force for the adsorption process.
基金This work was supported by the National Natural Basic Research Program of China （No.2013CB922200）,the National Natural Science Foundation of China （No.11674128, No.11474129, and No.11504129）, Jilin Province Scientific and Technological Development Program, China （No.20170101063JC）, the Thirteenth Five- Year Scientific and Technological Research Project of the Education Department of Jilin Province, China （No.n00）.
文摘The mixture of graphene oxide （GO） and dye molecules may provide some new applications due to unique electronic, optical, and structural properties. Methylene blue （MB）, a typ- ical anionic dye, can attach on GO via π-π stacking and electrostatic interaction, and the molecule removal process on GO has been observed. However, it remains unclear about the ultrafast carrier dynamics and the internal energy transfer pathways of the system which is composed of GO and MB. We have employed ultrafast optical pump-probe spectroscopy to investigate the excited dynamics of the GO-MB system dispersed in water by exciting the samples at 400 nm pump pulse. The pristine MB and GO dynamics are also analyzed in tandem for a direct comparison. Utilizing the global analysis to fit the measured signal via a sequential model, five lifetimes are acquired：（0.61±0.01） ps, （3.52±0.04） ps, （14.1±0.3） ps, （84±2） ps, and （3.66±0.08） ns. The ultrafast dynamics corresponding to these lifetimes was analyzed and the new relaxation processes were found in the GO-MB system, compared with the pristine MB. The results reveal that the functionalization of GO can alter the known decay pathways of MB via the energy transfer from GO to MB in system, the increased intermediate state, and the promoted energy transfer from triplet state MB to ground state oxygen molecules dissolved in aqueous sample.
基金financially supported by the National Natural Science Foundation of China (No. 51002042, No. 40902020 and No. 51072044)the Fundamental Research Funds for the Central Universities (No. 2013HGQC0015)+1 种基金Scientific Research Foundation for the Returned Scholars from Ministry of Education of China (No. 2013JYLH0774)Project from Ministry of Science and Technology of Anhui Province (No. J2014AKKJ0002)
文摘An activation process for developing the surface and porous structure of palygorskite/carbon（PG/C） nanocomposite using ZnC l2 as activating agent was investigated. The obtained activated PG/C was characterized by X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）, field-emission scanning electron microscopy（SEM）, and Brunauer-Emmett-Teller analysis（BET） techniques. The effects of activation conditions were examined,including activation temperature and impregnation ratio. With increased temperature and impregnation ratio, the collapse of the palygorskite crystal structure was found to accelerate and the carbon coated on the surface underwent further carbonization. XRD and SEM data confirmed that the palygorskite structure was destroyed and the carbon structure was developed during activation. The presence of the characteristic absorption peaks of C_C and C-H vibrations in the FTIR spectra suggested the occurrence of aromatization. The BET surface area improved by more than 11-fold（1201 m2/g for activated PG/C vs. 106 m2/g for PG/C） after activation, and the material appeared to be mainly microporous. The maximum adsorption capacity of methylene blue onto the activated PG/C reached 351 mg/g. The activated PG/C demonstrated better compressive strength than activated carbon without palygorskite clay.
基金supported by the National Natural Science Foundation of China (No. 20907022,21003094)the Doctoral Program of Higher Education of China(No. 200800551003,20100032120066)the Special Projects of Environmental Protection (No. 2009ZX07526,2009ZX07208,200909101,2009GJA10021)
文摘Cerium-doped SiO2/TiO2 nanostructured fibers were fabricated by electrospinning technology. The prepared fibers were characterized by thermogravimetric analysis （TGA）, scanning electron microscopy （SEM）, X-ray diffraction （XRD） and Fourier transform infrared spectroscopy （FT-IR）. Using the fibers as catalysts, photoeatalytic degradation of Methylene Blue （MB） aqueous solution was carded out under simulated sunlight. The 0.2% Ce doping proved to be the optimal concentration for the doping of TiO2/SiO2, compared to other Ce-doped molar concentrations. The 0.2% Ce-doped SiOdTiO2 fibers exhibited higher photocatalytic activity than industrial Degussa P25 and the samples doped with only Ce or SIO2. The reasons for improving the photocatalytic activity were also discussed. Several operational parameters were studied, which showed that the photocatalytic efficiency of MB was influenced by parameters such as the initial dye concentration, the initial pH, inorganic anions, and so on. In addition, the influences of an electron acceptor and a radical scavenger suggested that OH was the dominant photooxidant during the photocatalytic process. The reuse evaluation of the fibers indicated that their photocatalytic activity had good stability.
基金Project supported by the "863 Program" of the Ministry of Science & Technology of China (2006AA06Z348)
文摘Rare earth ions La3＋ and Eu3＋ co-doped TiO2 photocatalyst （La-Eu/TiO2） was prepared by sol-gel method, and characterized by various techniques such as X-ray diffraction （XRD）, specific surface area and porosity （BET and BJH）, scanning electron microscopy （SEM）, high resolution transmission electron microscopy （HRTEM）, UV-vis diffuse reflectance spectroscopy （DRS） and X-ray photoelectron spectroscopy （XPS）. The photocatalytic activity of the La-Eu/TiO2 was evaluated by the degradation of methylene blue （MB） under UV light irradiation. The catalyst had a relatively uniform particle diameter distribution in the range of 40–60 nm. When calcining at 600℃, the XRD patterns of La-Eu/TiO2 indicated the anatase phase, while the XPS patterns showed the Ti4＋, La3＋ and Eu3＋ ions existence. The DRS spectra showed red shift in the band-gap transition. The experimental results of MB degradation demonstrated that the photocatalytic activity of La-Eu/TiO2 was significantly enhanced due to better separation of photogenerated electron-hole pairs.
文摘Polyaniline （PAn） sensitized nanocrystalline TiO2 composites （TiO2/PAn） were successfully prepared and used as an efficient photocatalyst for the degradation of dye methylene blue （MB）. The results showed that PAn was able to sensitize TiO2 efficiently and the composite photocatalyst could be activated by absorbing both the ultraviolet and visible light （λ： 190 ～ 800 nm）, whereas pure TiO2 absorbed ultraviolet light only （λ 〈 380 nm）. Under the irradiation of natural light, MB could be degraded more efficiently on the TiO2/PAn composites than on the TiO2 Furthermore, it could be easily separated from the solution by simple sedimentation.
基金supported by the Science and Technology Department of Zhejiang Province (No. 2010C32051)the Ministry of Science and Technology (No. 2011BAD01B03-5-1), China
文摘Tea (Camellia sinensis L.) seed shells, the main byproduct of the manufacture of tea seed oil, were used as precursors for the preparation of tea activated carbon (TAC) in the present study. A high yield (44.1%) of TAC was obtained from tea seed shells via a one-step chemical method using ZnCl2 as an agent. The Brunauer-Emmett-Teller (BET) surface area and the total pore volumes of the obtained TAC were found to be 1 530.67 mg2/g and 0.7826 cm3/g, respectively. The equilibrium adsorption results were complied with Langmuir isotherm model and its maximum monolayer adsorption capacity was 324.7 mg/g for methylene blue. Adsorption kinetics studies indicated that the pseudosecond-order model yielded the best fit for the kinetic data. An intraparticle diffusion model suggested that the intraparticle diffusion was not the only rate-controlling step. Thermodynamics studies revealed the spontaneous and exothermic nature of the sorption process. These results indicate that tea seed shells could be utilized as a renewable resource to develop activated carbon which is a potential adsorbent for methylene blue.
基金the Universiti Teknologi MARA,Institute of Research Management and Innovation(Institut Pengu-rusan Penyelidikan&Inovasi)for funding this project underLES-TARI grant(600-IRMI 5/3/LESTARI(037/2019)).The authors Zeid A.ALOthman and Mohammad Rizwan Khan are thankful to the Researchers Supporting Project(RSP-2020/138),King Saud University,Riyadh,Saudi Arabia.
文摘In this study,an alternative precursor for production of activated carbon was introduced using dragon fruit(Hylocereus costaricensis)peel(DFP).Moreover,KOH was used as a chemical activator in the thermal carbonization process to convert DFP into activated carbon(DFPAC).In order to accomplish this research,several approaches were employed to examine the elemental composition,surface properties,amorphous and crystalline nature,essential active group,and surface morphology of the DFPAC.The BrunauerEmmettTeller test demonstrated a mesoporous structure of the DFPAC has a high surface area of 756.3 m2g 1.The cationic dye Methylene Blue(MB)was used as a probe to assess the efficiency of DFPAC towards the removal of MB dye from aqueous solution.The effects of adsorption input factors(e.g.DFPAC dose(A:0.040.12 g L 1),pH(B:310),and temperature(C:3050℃))were investigated and optimized using statistical analysis(i.e.BoxBehnken design(BBD)).The adsorption kinetic model can be best categorized as the pseudofirst order(PFO).Whereas,the adsorption isotherm model can be best described by Langmuir model,with maximum adsorption capacity of DFPAC for MB dye was 195.2 mg g 1 at 50℃.The adsorption mechanism of MB by DFPAC surface was attributed to the electrostatic interaction,pp interaction,and Hbonding.Finally,the results support the ability of DFP to be a promising precursor for production of highly porous activated carbon suitable for removal of cationic dyes(e.g.MB).
基金the Specialized Research Fund for the National Natural Science Foundation of China (Nos.21567013, 51504119)the National High Technology Research and Development Program (863) of China (No. 2015AA020201)+1 种基金the Yunnan Applied Basic Research Project (No.2015FB129)the Yunnan Provincial Science and Technology Innovation Talents Scheme Technological Leading Talent (No.2013HA002)
文摘The methylene blue（MB）removal abilities of raw activated carbon and iron/cerium modified raw activated carbon（Fe–Ce-AC）by adsorption were researched and compared.The characteristics of Fe–Ce-AC were examined by N2adsorption,zeta potential measurement,FTIR,Raman,XRD,XPS,SEM and EDS.After modification,the following phenomena occurred：The BET surface area,average pore diameter and total pore volume decreased;the degree of graphitization also decreased.Moreover,the presence of Fe3O4led to Fe–Ce-AC having magnetic properties,which makes it easy to separate from dye wastewater in an external magnetic field and subsequently recycle.In addition,the equilibrium isotherms and kinetics of MB adsorption on raw activated carbon and Fe–Ce-AC were systematically examined.The equilibrium adsorption data indicated that the adsorption behavior followed the Langmuir isotherm,and the pseudo-second-order model matched the kinetic data well.Compared with raw activated carbon,the maximum monolayer adsorption capacity of Fe–Ce-AC increased by27.31%.According to the experimental results,Fe–Ce-AC can be used as an effective adsorbent for the removal of MB from dye wastewater.
基金the Islamic Azad University,Lahijan and Rasht Branches for their help and support
文摘The tea wastages could remove methylene blue（MB） as a cationic dye from waste water corresponding to second-order kinetic model.Thermodynamic studies showed that adsorption equilibrium constant（KL） and maximum adsorption capacities（Q（max）） were increased with increasing temperature.The removal efficiency of MB for Co 0.01 mmol/L at optimum conditions was about 85%. The maximum uptake capacity（Q（max）） of methylene blue in a batch reactor was 0.328,0.542 and 0.659 mmol/g at 15,25 and 40℃, respectively.The enthalpy change（ΔH） and entropy change（ΔS） were 11.356 kJ/mol and 20.563 J/（mol K）,respectively.
基金Financial supports from National Natural Science Foundation of China （No. 40472026 and No. 40072017）
文摘The adsorption kinetics of methylene blue from aqueous solutions on purified palygorskite was investigated. The kinetics data related to the adsorption of methylene blue from aqueous solutions are in good agreement with the pseudo-second order equation in ranges of initial concentration of 120-210 mg/L, oscillation speed of 100-200 r/min and temperature of 298-328K. The experimental results show that methylene blue is only adsorbed onto the external surface of purified palygorskite, and the apparent adsorption activation energy is 13.92 kJ/mol. The relatively low apparent adsorption activation energy suggests that the adsorption of methylene blue involves in not only a chemical, but also a physical adsorption process, and it is controlled by the combination of chemical adsorption and fiquid-film diffusion.
