Absorption Of Pb2 Research Articles

Pengaruh Waktu Kontak dan Kecepatan Pengadukan Terhadap Penyerapan Ion Logam Pb2+ Menggunakan Biosorben Kulit Buah Naga Merah (Hylocereus polyrhizus)

The Pb2+ ion is the most common and highly toxic metal ion that can be found in industrial waste. if it enters a water body, it will be difficult to degrade and easily accumulate in the body of organisms. This study aims to reduce the impact of Pb2+ ion pollution in the waters. The biosorption method was chosen in batches by utilizing plantation waste, namely dragon fruit peel as a biosorbent in the absorption of Pb2+ ions, because it is cheap, safe, and effective. Dragon fruit peel contains lignin and cellulose which contain active groups so that it ispotential to be used as a biosorbent. The result showed that the dragon fruit peel adsorbent was able to absorb Pb 2+ ions at an optimum contact time 70 minutes with a stirring speed of 200 rpm which was analyzed using an atomic absorption with the highest absorption capacity of 32,74 mg/g.

Theoretical approach on Hg2+, Pb2+ and Cd2+ ions adsorption via phographene

Due to widespread concerns regarding health and environmental risks associated with heavy metal ions, wastewater must be cleaned of them. As part of this study, phographene (PG) is investigated for removing Pb2+, Hg2+, and Cd2 + ions from wastewater. It has been proven that PG can be effective in removing heavy metals from watery media. The present study utilizes density functional theory (DFT). By the absorption of Pb2+, Hg2+, and Cd2 + ions, the pure PG gap (HOMO-LUMO) is significantly narrowed. Research shows that faster electron transport rates result in larger charge transfers between cations and PGs and higher binding energies. In the studied complexes, time-dependent DFT analysis indicates a charge transfer between the ligand and the metal. Based on the theory analysis conducted in this paper, experimental studies can be conducted to find PG-based materials that effectively remove contaminants from wastewater.

Effect of CeO2-Reinforcement on Pb Absorption by Coconut Coir-Derived Magnetic Biochar.

Magnetic separable biochar holds great promise for the treatment of Pb2+-contaminated wastewater. However, the absorption effect of unmodified magnetic biochar is poor. Considering this gap in knowledge, CeO2-doped magnetic coconut coir biochar (Ce-MCB) and magnetic coconut coir biochar (MCB) for Pb2+ absorption were prepared by the impregnation method, and the efficiency of Ce-MCB for Pb2+ absorption was evaluated in comparison with MCB. Conducting the absorption experiments, the study provided theoretical support for the exploration of the absorption mechanism. The quantitative analysis exposed that the enhanced absorption capacity of Ce-MCB was attributed to the increase in oxygen-containing functional groups and mineral precipitation. The Langmuir and Freundlich isotherm model showed that Ce-MCB is a suitable adsorbent for Pb2+. The absorption characteristics of Ce-MCB was fit well with the pseudo-second-order (PSO) and Langmuir models, which revealed that the absorption of Pb2+ in water was monolayer chemisorption with a maximum theoretical adsorption capacity of 140.83 mg·g-1. The adsorption capacity of Ce-MCB for Pb(II) was sustained above 70% after four cycles. In addition, the saturation magnetization intensity of Ce-MCB was 7.15 emu·g-1, which was sufficient to separate out from the solution. Overall, Ce-MCB has wide application prospects in terms of biomass resources recycling and environmental conservation.

Synthesis and application of starch-stablized Fe–Mn/biochar composites for the removal of lead from water and soil

Starch-stablized and Fe/Mn bimetals modified biochar derived from corn straw (SFM@CBC and SFM@CBC-350) were firstly prepared, characterized (FTIR, XRD, SEM, EDS, BET and XPS), and applied in Pb removal from water and soil. SFM@CBC and SFM@CBC-350 displayed highly effective adsorption performance of Pb2+ from wastewater with the maximum adsorption capacity of 170.91 mg g−1 and 190.17 mg g−1, respectively, which were much greater than that of FM@CBC (149.25 mg g−1) and CBC (101.10 mg g−1). Studies of adsorption kinetics, isotherms and thermodynamics indicated that the absorption of Pb2+ by SFM@CBC and SFM@CBC-350 was spontaneous and endothermic reaction, and it was controlled by monolayer chemisorption. The mechanism studies indicated that Pb2+ removal involved with multiple mechanism, including complexation (dominant process confirmed by XPS analysis), physical adsorption, electrostatic attraction, and cation exchange. The reusability test demonstrated that SFM@CBC and SFM@CBC-350 had very good stability and reusability. In addition, in order to further explore Pb removal performance of the modified biochar, SFM@CBC-350 was used in soil-ryegrass pot systems. Compared with the controls, the addition of SFM@CBC-350 reduced Pb content in soil and ryegrass, increased the biomass and total chlorophyll content, reduced the activity of antioxidant enzymes (CAT, SOD, MDA and POD) and ROS fluorescence intensity of ryegrass, thus alleviating Pb stress of ryegrass. Besides, the addition of SFM@CBC-350 could increase the richness and diversity of soil microorganisms, which was beneficial to the growth of ryegrass. Hence, SFM@CBC-350 has the potential of being used as a green, efficient and promising adsorbent in Pb removal from wastewater and soil.

Deciphering the role of selenium‐enriched rice protein hydrolysates in the regulation of Pb2+‐induced cytotoxicity: an in vitro Caco‐2 cell model study

SummaryLead (Pb), a well‐known toxic metal, has a potential of adverse effects on human health. Selenium (Se) can reduce the toxicity caused by heavy metals. In this study, we investigated the protection mechanism of the purified Se‐enriched rice protein hydrolysates (SPHs‐2) on the Pb2+‐induced cytotoxicity. A Caco‐2 cell model was established to characterise the effect of SPHs‐2 on Pb2+ absorption in the simulated small intestine. Results showed that 1000 μg mL−1 of SPHs‐2 treatment could significantly increase cell viability by 19.43% in Pb2+‐treated Caco‐2 cells (P < 0.05). Furthermore, the absorption of Pb2+ was successfully retarded by incorporating SPHs‐2. Interestingly, selenomethionine (SeMet) was identified as a major Se species in SPHs‐2 by HPLC‐ICP‐MS, and SeMet played a crucial role in regulating Pb2+ intestinal absorption via forming complexes. In light of this, SPHs‐2 may serve as a potential Pb2+‐chelating peptide for developing novel functional food and protecting human health.

Preparation of anionic-cationic co-substituted hydroxyapatite for heavy metal removal: Performance and mechanisms

Sodium, silicate and carbonate ions co-substituted hydroxyapatite adsorbent (Na-SiCHAP) was prepared by sonochemistry coprecipitation. The effect of a variety of parameters on the adsorption of Pb2+ and Cd2+ by Na-SiCHAP were performed. The adsorption process of heavy metal ions was found to follow the pseudo-second-order kinetic equation and Langmuir adsorption model. The maximum absorption capacity (Qm) of Na-SiCHAP for Pb2+ and Cd2+ ions in 303 K were 698.68 and 129.60 mg g−1 according to the Langmuir adsorption model, respectively. The thermodynamic parameters (ΔG0 <0, ΔS0 >0, ΔH0 >22kJ·mol-1) indicated that the absorption of Pb2+ and Cd2+ on the Na-SiCHAP was spontaneous and endothermic, and the Na-SiCHAP adsorbed mainly via chemical adsorption. Ion exchange of Pb2+ and Cd2+ for Ca2+ and Na+ was one of the principal mechanisms, followed by precipitation and electrostatic interactions. Furthermore, the well stability properties of the Na-SiCHAP adsorbent were confirmed by recycling assays. These data indicate that Na-SiCHAP may be a good adsorbent for the rapid removal of heavy metal ions from aqueous solutions.

Study on absorption of Cd2+ and Pb2+ by bamboo shoots superfine powder modified at high temperature

In order to find better heavy metal absorption material, this modification by heating bamboo shoots superfine powder at 50 °C with 5, 30 and 90 min. The effect on the absorption of Pb2+ and Cd2+ was determined through scanning electron microscopy (SEM) and infrared spectra (FTIR). The results showed that the heating time of 30 min, its absorption of Cd2+ and Pb2+ was best, and the highest absorption Cd2+ and Pb2+ were 56.46% and 74.18%, respectively. The heating time for 5 min and 90 min, absorption rate of the kinds of ions was lower than those modified.

重金属铅与两种淡水藻的相互作用

PDF HTML阅读 XML下载 导出引用 引用提醒 重金属铅与两种淡水藻的相互作用 DOI: 10.5846/stxb201211051545 作者: 作者单位: 安徽师范大学生命科学院,安徽师范大学生命科学院,安徽师范大学生命科学院,安徽师范大学生命科学院,安徽师范大学生命科学院,安徽师范大学生命科学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31170443） Interactions between heavy metal lead and two freshwater algae Author: Affiliation: The Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province,College of Life Sciences,Anhui Normal University,College of Life Sciences,Anhui Normal University,The Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province,College of Life Sciences,Anhui Normal University,The Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province,College of Life Sciences,Anhui Normal University,The Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province,College of Life Sciences,Anhui Normal University,The Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province,College of Life Sciences,Anhui Normal University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为了研究重金属铅与淡水藻类之间的相互作用，采用不同Pb2+浓度处理铜绿微囊藻（Microcysis aeruginosa Kutz.）和斜生栅藻,分别对两种藻的生物量、藻液电导率、O2-·含量、过氧化物酶（POD）、过氧化氢酶（CAT）活性以及藻对Pb2+的吸收作用等进行了测定，并通过扫描电镜观察了不同Pb2+浓度处理下两种藻细胞的表面结构。结果显示：（1）Pb2+浓度低于3 mg/L促进铜绿微囊藻生长，高于9 mg/L抑制其生长；但在3-12 mg/L范围内，Pb2+均明显抑制了斜生栅藻的生长，说明斜生栅藻对Pb2+毒性的敏感程度要高于铜绿微囊藻。（2）受到铅离子的胁迫，两种藻细胞膜通透性均有一定改变，扫描电子显微镜的照片观察，两种藻细胞表面的絮状物随着Pb2+的升高而增多，尤其是斜生栅藻细胞结构改变明显，多数细胞变形破裂；同时，O2-·含量升高，POD、CAT活性早期均可随Pb2+的增加而上升，表明氧自由基的产生增多以及由其引起的细胞生理生化改变可能是铅离子作用于藻细胞的主要机制。（3）两种淡水藻对Pb2+均有吸收作用，单位量藻细胞内，斜生栅藻对Pb2+的吸收能力好于铜绿微囊藻。所有结果提示：斜生栅藻不仅可以作为对重金属敏感的指示生物来监测水体Pb2+污染程度；同时由于斜生栅藻比铜绿微囊藻具有更好的Pb2+吸收能力，因此还可以利用斜生栅藻作为处理水体Pb2+的生物材料。 Abstract:To get a better understanding of interactions between heavy metal lead and freshwater algae Microcysis aeruginosa Kutz. and Scenedesmus obliquus (Turp.) Kutz., the algal biomass, electrical conductivity (EC) of supernatant, concentration of superoxide anion radical (O2-·), activities of POD and CAT as well as the absorption of Pb2+ by algal were determined respectively at different concentrations of Pb2+, and the surface structure of two algae cells was contrasted by scanning electron microscopy. The results showed as follows: (1) 3 mg/L of Pb2+ accelerated the growth of M. aeruginosa, and the opposite effects were observed when exposed to more than 9 mg/L of Pb2+; however, the growth of S. obliquus was obviously inhibited when the concentrations of Pb2+ ranged from 3 to 12 mg/L. The effects of Pb2+ on the two kinds of freshwater algae indicated that S. obliquus was more sensitive to the Pb2+ pressure. (2) The membrane permeability of the two algae cells was changed under the stress of Pb2+. The photos of scanning electron microscopy showed that the superficial flocs of the two algae cells increased with the increasing of Pb2+, and numerous cells deformed or ruptured evidently, especially for S. obliquus. Meanwhile, the increases of O-2 contents were exhibited and the activities of POD and CAT in the two algae were advanced with increasing of Pb2+ concentration at the early stage, which indicated that the main mechanisms of Pb2+ acting on two algae involve the increasing production of superoxide anion radical and the accompanying physiological and biochemical changes of the algae. (3) Pb2+ can be absorbed by the two algae, and moreover S. obliquus had higher capacity of Pb2+ absorption than M. aeruginosa did at the unit cells. From the above points, compared with the M. aeruginosa, S. obliquus can be used not only as a biological indicator for monitoring heavy metal pollution levels, but also as a biological material to deal with water Pb2+ contamination due to its ability of Pb2+ absorption. 参考文献 相似文献 引证文献

A Novel Chromogenic System of Pb&lt;sup&gt;2&lt;/sup&gt;&lt;sup&gt;+&lt;/sup&gt; - 4, 5- Dibromo- o- Nitrophenylfluorone in the Coexistence of Carbon Nanotubes and CTMAB

A novel chromogenic system of Pb2+ with 4, 5- dibromo- o- nitrophenylfluorone (DBONPF) was developed by the synergetic effect of carboxylic carbon nanotubes (c-CNTs) and cationic surfactants CTMAB. The absorption of Pb2+ by DBONPF can be improved by the addition of a nano-material and a surfactant. Comparative experiments proved that the absorption of the complex of Pb- DBONPF was increased by 153.9% due to the conjugated system of the c-CNTs and the solubilization of CTMAB. The proposed method was applied to the determination of pb2+ in cosmetics satisfactorily

The Studies of Adsorption of Heavy Metal Ions of Lead and&lt;sup&gt; &lt;/sup&gt;Copper by Distillers' Grains

The absorption of Cu2+ and Pb2+ in the heavy metal wastewater by distillers' grains can not only solve the problem of environmental pollution, but also change distillers' grains waste into resource. Structural characteristics of distillers' grains and its adsorption behaviors for the heavy metal ions of Cu2+ and Pb2+ were studied and effects of various parameters including pH, temperature, distillers' grains dose, initial Cu2+ and Pb2+ concentration and absorbed time on the absorption of Pb2+ and Cu2+ were evaluated. Sorption isotherms were also investigated. Results show that the rough surface, loose internal structure and hydroxy and amide groups of the distillers' grains are beneficial to the adsorption of Cu2+ and Pb2+ in the wastewater. The removal rate of the distillers' grains for Pb2+ (20.00 mg L−1) and Cu2+ (20.00 mg L−1) are, respectively, 96.72% and 87.70% under optimized conditions. The equilibrium sorption data are well demonstrated by Langmuir model.

Investigation on K2Ti4O9 Whisker Absorbent and Applications in Heavy Metal Ions Removal

The present paper deals with absorption of heavy ions of Pb2+, Cd2+ in water on potassium tetratitanate whisker (PTW). The effects of quantity of PTW, time and pH value on the absorption is studied. The test results show that the absorption efficiency of PTW increases with the quantity of absorbent, time and pH value. The absorption of Pb2+ and Cd2+ ions on PTW follows Freundlich's Equation. The property of PTW regeneration is also investigated in the present paper. The possibility of using PTW to treat industrial waste water containing heavy metal ions is discussed.

Photoluminescence properties ofPb2+ centres in CaS:Pb thin films

The emission and excitation spectra of CaS:Pb thin films have been obtained at 10 Ktogether with the emission decay curves. The CaS:Pb samples were preparedwith the variation of the concentration and the spatial uniformity of activePb2+ ions within the CaS host matrix using atomic layer deposition (ALD) andtetraethyl lead (TEL) as the Pb precursor. The deep blue emission at thewavelength of 400–450 nm was shown to be regulated by means of the homogeneousdistribution of the luminescent centres rather than the number of Pb ions. Atthe same concentration and uniformity, the higher growth temperature of380 °C was found to be more advantageous for the deep blue emission than350 °C.These observations have been interpreted in terms of the selective incorporation of blue-emittingPb2+ dimers achieved by the controlled ALD technique and the preferentialreactivity of TEL. The excitation spectra indicated that the absorption ofPb2+ monomers and CaS matrix as well as the dimeric luminescent centres induced blue emissionthrough efficient energy transfer to the dimer centres. In addition, the visible emissionabove 450 nm is believed to be attributable to the formation of aggregates larger thandimers in view of the measured decay times.

Controlled Synthesis of Semiconductor PbS Nanocrystals and Nanowires Inside Mesoporous Silica SBA-15 Phase

A new flexible approach is developed to fabricate uniform nanocrystals and nanowires of binary compound semiconductor PbS inside the channels of mesoporous silica SBA-15. The approach combines functionalization of the channel surface with thiol groups, absorption of Pb2+, and heating in N2 atmosphere at high temperature. The separate introduction of thiol groups and Pb2+ makes the loading of a binary compound efficient and as easy as the loading of a single element. The nanocrystals are uniform and their sizes (5 nm) are consistent with the diameter of mesoporous SBA-15. The diameter of the PbS nanowires is about 6 nm and the length is several hundred nanometers. TEM images first intuitively confirm the formation of binary sulfide nanocrystals and nanowires dispersing uniformly inside the channels of mesoporous SBA-15. The key for transition from nanocrystals to nanowires is to increase the amount of the Si−OH group on the channel surface of SBA-15, and ethanol extraction proves to be effective to keep large amount of Si−OH groups during removing of the block copolymer. A massive blue shift is observed in photoluminescence spectra, and this clearly shows the quantum size effects of the PbS nanocrystals and nanowires.