CHEMICAL ENGINEERING JOURNAL
·
2014
·
IF 4.058
Lixin Zhou,Shengdong Pan,Xiaohong Chen,Yonggang Zhao,Baobo Zou,Micong Jin
A novel core–shell covalently functionalized Fe 3 O 4 coated SiO 2 decorated multi-walled carbon nanotubes (Fe 3 O 4 @SiO 2 –MWCNTs) adsorbent was synthesized and characterized by scanning electron microscopy, transmission electron microscopy, Fourier Transform Infrared Spectrum (FTIR), Thermogravimetry, X-ray diffraction and magnetic measurements. The pentachlorophenol (PCP) adsorption effect factors of initial concentration, contact time, solution pH and temperature were investigated in detail. It was found the absorption capacity was strongly depended on pH, and the maximum adsorption value for PCP (96.4 mg/g) was obtained at pH 2.5. The equilibrium was attained within 30 min, and the adsorption kinetics was better described by pseudo-second-order kinetic model. The data pointed out excellent fit to Freundlich isotherm model. Thermodynamic parameters such as standard enthalpy (Δ H θ ), standard entropy (Δ S θ ) and standard free energy (Δ G θ ) showed that the adsorption of PCP onto Fe 3 O 4 @SiO 2 –MWCNTs was spontaneous, endothermic and random within the temperature range of 288–318 K. The results indicate that the Fe 3 O 4 @SiO 2 –MWCNTs adsorbent is a potential low-cost effective material for PCP removal from contaminated wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Frontiers in Bioengineering and Biotechnology
·
2022
·
IF 6.064
Ma Anzhou,Ma Jianpeng,Chen Xianke,Zhuang Guoqiang
Highly chlorinated benzenes usually have a low efficient degradation in environment. Here we proposed a synergistic removal strategy of pentachlorobenzene (PeCB) using Pseudomonas sp. JS100 coupled with immobilized nanoscale zero-valent iron (NZVI). The structural and textural features of the synergistic system were characterized by X-ray powder diffraction, field emission scanning electron microscopy, and a specific surface area and pore size analysis. Nanoscale zero-valent iron particles were dispersed and attached to the biofilter, which increased the specific surface area to 34.5 m2 g−1. The batch experiment revealed that the removal efficiency of PeCB reached 80.2% in the synergistic system within 48 h. The degradation followed pseudo-first-order reaction kinetics, and the reaction rate constant was measured to be 0.0336 h−1. In the degradation mechanism, PeCB was degraded by NZVI to lower chlorobenzenes, which were utilized by Pseudomonas sp. JS100 as nutrients, thereby achieving rapid removal of PeCB.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2022
·
IF 8.943
Fengjie Chen,Wanchao Yu,Yarui Wang,Silong Wang,Ying Liang,Ling Wang,Yong Liang,Lixia Zhao,Yawei Wang
Photodegradation is a new approach for the removal of pentachlorophenol (PCP). Photooxidation degradation (using hydroxyl radicals) exhibits better performance to remove PCP than photoreduction degradation, but the former will lead to an increase in the production of toxic by-products such as tetrachloro-1,4-benzoquinone (TCBQ). Thus, a new strategy is required to enhance PCP photodegradation and simultaneously inhibit toxic intermediates production. Herein, TiO 2 (P25)/polydopamine (PDA)/BiOBr was synthesized and used to photodegrade PCP. Based on the relative position of the CB and VB of P25 and BiOBr, and PDA as an electron transfer mediator, a high number of holes, electrons, and superoxide anions were produced instead of hydroxyl radicals . The photocatalytic activity of P25/PDA/BiOBr exhibited the best performance among as-prepared samples, reaching a k (pcp) value of 0.4 min −1 (20 μM PCP) under UV light irradiation within 10 min. According to chemiluminescence and acute toxicity assays, relative to P25, the toxic intermediates of TCBQ and trichlorohydroxy-1,4-benzoquinone (OH-TrCBQ) generation was greatly reduced over P25/PDA/BiOBr, with a lack of toxic product generation during PCP photodegradation process. These findings provide an alternative strategy to achieve greener and more efficient organic pollutant photodegradation.
研究领域:
环境科学
·
光催化材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTIK
·
2020
·
IF 2.187
Ghorban Asgari,Abdolmotaleb Sidmohammadi,Ali Reza Rahmani,Mohamah Reza Samargandi,Hossein Faraji
This study was conducted to investigate the performance of sodium hydrosulfite-mediated photoreduction (SMP) process for the reduction of the pentachlorophenol (PCP). The influence of various parameters, quenchers and anions in water, were investigated on the performance of the SMP. The PCP degradation rates by SMP, UV alone and sodium hydrosulfite alone were achieved 100 %, 65 % and 16 %, respectively (under optimum conditions: sodium hydrosulfite dosage, 100 mg L −1 ; pH, 7.0 and reaction time, 80 min). Also, the kinetic studies confirmed the superiority of SMP than the other process (r obs values for SMP were 69 and 9.8 times of the sodium hydrosulfite alone and UV alone, respectively).Under the selected conditions 56 % of total organic carbon (TOC) was mineralized. The amounts of energy consumed for SMP, UV alone and sodium hydrosulfite alone were estimated 16, 35 and 19 and kWh m -3 , respectively. The results indicated adding quenchers in the solution, significantly was declined degradation performance . Therefore, it was found the SMP process due to smaller total cost and energy consumption and also the higher r obs , might be an efficient method for the removal of pentachlorophenol form aqueous solution.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Ming Lei,Yao Tang,Huimin Wang,Lihua Zhu,Guihua Zhang,Yu Zhou,Heqing Tang
It is still very difficult to achieve rapid cleavage of C-Cl bond of highly-chlorinated benzenes by catalytic reduction process under mild conditions. By using pentachlorobenzene (PentaCB) as a representative of highly-chlorinated benzenes, we proposed a strategy to achieve rapid and complete dechlorination of highly-chlorinated benzenes by exploiting palladium with low content deposited g-C 3 N 4 (Pd/g-C 3 N 4 ) as a catalyst with NaBH 4 as a reductant. Under favorable conditions, this strategy yielded a dechlorination efficiency of 100% for PentaCB (0.4 mmol L −1 ) in methanol solution at 30 °C within 20 min, and especially the consumption of NaBH 4 is as low as 10 mmol L −1 with a molar ratio of Cl atoms to NaBH 4 of only 1:5. A hydro-dechlorination pathway was confirmed to dominate the dechlorination of PentaCB, which involves active hydrogen species (H*) as being identified by electron spin resonance (ESR) monitoring and isotope labelling experiments. The dechlorination rate constant value of chlorobenzenes (CBs) was only a little dependent on the number of chlorine atoms and the chlorine atom with smaller steric hindrance was prior to be substituted by H*. A catalytic mechanism that Pd nanoparticles played an important role on both the weakening/breaking of C-Cl bond and the formation of active hydrogen species was further clarified: Pd exerts affinity interaction on chlorine atoms at ortho -position of CBs molecules to form adsorbed state [CBs] ads ; H* was formed on the Pd surface due to its strong ability in H* retainment; subsequently the generated H* attacks the C-Cl bond in [CBs] ads to achieve hydrodechlorination. The new method provides a highly efficient method to remove halogenated pollutants.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2012
·
IF 4.173
Min Yang,Aijuan Han,Junling Duan,Zhipeng Li,Yongchao Lai,Jinhua Zhan
In this study, an imprinted silica matrix of pentachlorophenol (PCP) co-loaded with Fe 3 O 4 nanoparticles and ZnS:Mn 2+ quantum dots (QDs) was fabricated. The introduction of Fe 3 O 4 nanoparticles to the imprinted matrix provided an easy way to separate PCP under an external magnetic field. ZnS:Mn 2+ QDs offered a readout signal to monitor the amount of PCP bound to the imprinted matrix and evaluate the efficiency of imprinting. X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy were used to characterize the imprinted matrix. The low angle X-ray diffraction and N 2 adsorption–desorption analysis indicated a periodic mesoporous structure. The as-synthesized imprinted matrix preferred to adsorb PCP rather than the other aromatic compounds like 2,4-dichlorophenoxy acetic acid, 2,4-dichlorophenol and phenol. The recoveries of spiked PCP in spring water and tap water with Fe 3 O 4 –ZnS:Mn 2+ co-loaded MIPs are 101% and 97%, respectively.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 13
·6840-6848
·
IF 2.936
Ying Guo,Bing Liao,Kun Wang,Yangyang Zhao,Qiwen Yong,Hongwei Zhao,Hao Pang
We prepared poly(N-isopropylacrylamide-co-4-tert-butylcalix[8]arene) (PNIPAM-TBCX) hydrogels by copolymerization of N-isopropylacrylamide (NIPAM) with 4-tert-butylcalix[8]arene (TBCX) to capture hazardous pentachlorophenol (PCP) from aqueous solution. Adsorption experiments showed that the adsorption capacities of PNIPAM-TBCX hydrogels reached 1.96, 2.08 and 2.02 mg PCP per 1 g of hydrogel, while the molar percentage ratio of TBCX in the hydrogels was as low as 0.5%, 0.7% and 1%. The equilibrium adsorption of PCP on the hydrogels was studied using different adsorption models. In addition, the PNIPAM-TBCX hydrogel still retained its performance when regenerated several times by immersing in water at 323 K.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2015
·
IF 4.143
Yan He,Fanfeng Zeng,Zhenghua Lian,Jianming Xu,Philip C. Brookes
Natural soil montmorillonite and kaolinite nanoparticles (NPs) were tested as efficient sorbents for organic contaminant (OC) removal through mimicking their natural environmental dispersive states. Sorption of both mineral NPs decreased with increasing pH with ionizable pentachlorophenol (PCP), but increased with pH with non-ionizable phenanthrene (PHE), within the pH range of 4–10. In contrast, sorption decreased consistently for both PCP and PHE, as a function of increasing ion concentration (0.001–0.1 mol L −1 ). Sorption differences were likely caused by the electrolytic conditions dependent upon surface chemistry of OCs and mineral NPs. The results confirmed that the highly dispersive soil mineral NPs would prevail over both engineered NPs and their regular μm-sized colloids for OC removal, due to their ecological advantages and higher sorption properties. This finding provided a realistic assessment of the environmental function of soil natural minerals in water once they are released from soil into OC polluted aqueous systems.
研究领域:
环境科学
·
土壤学
·
环境化学
·
纳米地球化学
·
污染控制
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2013
·
IF 2.004
Zhongjian Li,Min Yao,Jun Lin,Bin Yang,Xingwang Zhang,Lecheng Lei
The selective sorption of pentachlorophenol (PCP) in a multiple solute system provides the possibility of using the cetyltrimethylammonium bromide (CTMAB)/bentonite one-step process as a promising technique for hydrophobic organics removal from wastewater. The PCP sorption mechanism, especially the effects of coexisting solutes, was studied. Compared to raw bentonite and conventional CTMAB modified organobentonite, the one-step process exhibited higher PCP removal efficiency. In a single solute system, the PCP sorption isotherm implied that the dominating sorption mechanism is a partition mechanism. The logarithms of sorption coefficients (Kd) for different organics are linearly related to the logarithm of their octanol–water partition coefficients (Kow). In a multiple solutes system, phenol and 2,4-dichlorophenol (2,4-DCP) could effectively enhance PCP sorption. The PCP sorption coefficient increases in the order: PCP/phenol < PCP/2,4-DCP < PCP/phenol/2,4-DCP. The PCP sorption enhancement is likely resulted from the interlayer space expansion and the organic carbon content increase. On the basis of the comparison between the single and the multiple solute systems, phenol and 2,4-DCP sorption coefficients decrease in the order: Kd of a single solute system > Kd of a binary solute system > Kd of a ternary solute system, and no enhancement for phenol and 2,4-DCP sorption was observed.
研究领域:
环境科学
·
污染控制
✓ 已验证
DOI
高影响因子
Nanoscale
·
2012
·Vol. 4
·期 16
·5210-5216
·
IF 5.914
Qiao An,Peng Zhang,Jun-Mei Li,Wan-Fu Ma,Jia Guo,Jun Hu,Chang-Chun Wang
Highly active surface-enhanced Raman scattering (SERS) substrates of Ag nanoparticle (Ag-NP) modified Fe3O4@carbon core–shell microspheres were synthesized and characterized. The carbon coated Fe3O4 microspheres were prepared via a one-pot solvothermal method and were served as the magnetic supporting substrates. The Ag-NPs were deposited by in situ reduction of AgNO3 with butylamine and the thickness of the Ag-NP layer was variable by controlling the AgNO3 concentrations. The structure and integrity of the Fe3O4@C@Ag composite microspheres were confirmed by TEM, XRD, VSM and UV-visible spectroscopy. In particular, the Ag-NP coated Fe3O4@carbon core–shell microspheres were shown to be highly active for SERS detections of pentachlorophenol (PCP), diethylhexyl phthalate (DEHP) and trinitrotoluene (TNT). These analytes are representatives of environmentally persistent organic pollutants with typically low SERS activities. The results suggested that the interactions between the carbon on the microsphere substrates and the aromatic cores of the target molecules contributed to the facile pre-concentration of the analytes near the Ag-NP surfaces.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2013
·
IF 5.008
Xiaohong Jiang,Min Yang,Yanjing Meng,Wei Jiang,Jinhua Zhan
Cysteamine-modified silver nanoparticle aggregates has been fabricated for pentachlorophenol (PCP) sensing by surface-enhanced Raman spectroscopy (SERS) using a portable Raman spectrometer. The cysteamine monolayers could preconcentrate PCP close to the substrate surface through the electrostatic interaction, which makes the SERS detection of PCP possible. Moreover, the Raman bands of cysteamine could be used as the internal spectral reference in the quantitative analysis. Qualitative detection of PCP was carried out by SERS without any sample pretreatment. Quantitative analysis of PCP was further realized based on the prepared substrate, as the log–log plot of normalized SERS intensity of PCP versus its concentrations exhibits a good linear relationship. The SERS signals collected on 20 randomly selected points show that the relative standard deviation of the normalized Raman intensity is 5.8%, which indicates the substrate had good uniformity. The PCP sensor also shows good long-term stability in the analyte solution. The substrate was cyclic immersed into PCP and methanol solution; after several cycles, the sensor still had good adsorption to PCP, which revealed the sensor has good reusability. Coupling with a portable Raman spectrometer, the cysteamine-modified silver nanoparticle aggregates have the potential to be used for in situ and routine SERS analysis of PCP in environmental samples.
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2015
·
IF 2.711
Xiaolin Zhu,Kexin Zhang,Nan Lu,Xing Yuan
In the present study, a poly(Rhodamine B)/graphene oxide/multiwalled carbon nanotubes nanocomposite modified glass carbon electrode (PRhB/GO/MWCNTs/GCE) was developed for the simultaneous determination of 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP). The PRhB/GO/MWCNTs film was extensively characterized by emission scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy and electrochemical impedance spectroscopy (EIS). The electrochemical behaviors of 2,4,6-TCP and PCP were investigated by cyclic voltammetry, linear sweep voltammetry and differential pulse voltammetry. Due to the synergistic effect, the PRhB/GO/MWCNTs/GCE significantly facilitated the simultaneous electro-oxidation of 2,4,6-TCP and PCP with peak potential difference of 160 mV and enhanced oxidation currents. Under optimum conditions, the oxidation current of 2,4,6-TCP was linear to its concentration in the ranges of 4.0 × 10 −9 to 1.0 × 10 −7 M and 1.0 × 10 −7 to 1.0 × 10 −4 M with the detection limit (S/N = 3) of 8.0 × 10 −10 M. And the linear concentration ranges for PCP were 2.0 × 10 −9 to 1.0 × 10 −7 M and 1.0 × 10 −7 to 9.0 × 10 −5 M with the detection limit of 5.0 × 10 −10 M. Moreover, the proposed PRhB/GO/MWCNTs/GCE was successfully applied to the simultaneous determination of 2,4,6-TCP and PCP in practical water samples.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子