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Phytoremediation is currently a very popular remediation method for salvaging rare earth mining sites. However, there is still a challenge concerning how to use secondary resources such as plant biomass following the extraction of rare earth elements (REEs). Herein, Dicranopteris pedata (Houtt.) Nakaike, a REEs hyperaccumulator, served to fabricate REEs-rich carbonisation materials (REEs/C) at different temperatures. The results showed that the percentages of Pb(II) removed using REEs/C prepared at 400 °C (REEs/C-4) and 800 °C (REEs/C-8) were 85.1% and 84.0%, respectively. These amounts were better than that of REEs-C prepared at 600 °C (REEs/C-6 (67.0%)). Characterisation analysis confirmed that rich functional groups like aromatic, hydroxyl and C = C/C-C in REEs/C-4 provided more chelation sites to effectively complex with Pb(II), while the superior removal capacity of REEs/C-8 resulted from the enrichment of more REEs and abundant pore structure. Chemisorption, such as ion exchange and chelation, plays a significant role in adsorption. During the carbonisation process of REEs/C, the REEs enriched in Dicranopteris pedata contributed to the formation of rare earth oxides and oxygen vacancies in the material, and these properties enhanced the Pb removal ability of REEs/C. Moreover, the REEs contained in the material did not cause a leaching phenomenon during Pb removal, which is a safe and environmentally friendly material. Finally, the REEs/C was applied to wastewater, and it was found that this material could effectively adsorb Pb from wastewater. Overall, this study generates a new insight into: firstly, how to use phytoextracted biomass containing REEs as valuable REEs/C materials; and secondly, how to save the environment by using technology that promotes recycling of used materials. [ABSTRACT FROM AUTHOR]

AbstractThe current study was designed to investigate the potentials of using chia (Salvia hispanica) seed as an efficient biosorbent for the biosorption of Pb(II) and Cd(II) from aqueous solution. The batch biosorption process was employed to study the factors involved in the biosorption process, including biosorbent dosage, initial metal concentrations, pH, and contact time. Additionally, the Langmuir and Freundlich isotherm (L & F) models were evaluated. Besides, Scanning Electron Microscopy (SEM), x-ray diffractometer (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) analyses were used to characterize the biosorbent before and after biosorption. The optimal pH was determined to be 5.0 as this would reduce electrostatic repulsion, while extreme pH levels would hinder the process. It was found that increasing the biosorbent concentration reduced biosorption efficiency due to the constant biosorbent concentration and possible self-aggregation. Moreover, higher initial metal concentrations were found to enhance the biosorption capacity, which would stabilize after 70 min. Furthermore, Freundlich isotherm model demonstrating the best fit for the data. Also, L&F parameters illustrated favorable biosorption of Pb(II) and Cd(II) onto the chia seed. The process was identified as second-order kinetics, suggesting complexation exchange mechanisms. The Freundlich isotherm model indicated multilayer adsorption on heterogeneous surfaces. It was demonstrated that biosorption is spontaneous and endothermic, with increased randomness at the interface, thermodynamically. The mechanism involved ion exchange and surface complexation, as evidenced by the correlation between released cations and metal ion removal. [ABSTRACT FROM AUTHOR]

The extensive release of water contaminated with lead (Pb(II)) and antimony (Sb(V)) constitutes a serious threat to the human living environment and public health, necessitating immediate attention. In this study, a novel MnFe@SBA composite was synthesized using the hydrothermal method through the in situ growth of MnFe2O4 on SBA-15. The MnFe@SBA exhibits an amorphous structure with a high specific surface area of 405.9 m2/g and pore sizes ranging from 2 to 10 nm. Adsorption experiments demonstrated that MnFe@SBA removed over 99% of Pb(II) and 80% of Sb(V) within 120 min at initial concentrations of 10 mg/L, whereas both MnFe2O4 and SBA-15 exhibited poor adsorption capacities. Additionally, the MnFe@SBA displayed excellent tolerance towards coexisting cations, including Na+, K+, Mg2+, Ca2+, Zn2+, Ni2+, and Cd2+, as well as anions such as Cl−, NO3−, CO32−, and PO43−. The adsorption behavior of Pb(II) onto MnFe@SBA was satisfactorily described by the pseudo-second-order kinetic model and the Freundlich isotherm, while the adsorption of Sb(V) was well-fitted by the pseudo-second-order kinetic model and the Langmuir isotherm. At 318 K, the maximum adsorption capacities of MnFe@SBA for Pb(II) and Sb(V) were determined to be 329.86 mg/g and 260.40 mg/g, respectively. Mechanistic studies indicated that the adsorption of Pb(II) and Sb(V) onto MnFe@SBA involved two primary steps: electrostatic attraction and complexation. In conclusion, the MnFe@SBA is anticipated to serve as an ideal candidate for efficient removal of Pb(II) and Sb(V) from contaminated water. [ABSTRACT FROM AUTHOR]

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Pb(II) is a heavy metal that is harmful to health and the environment. This metal is often found in industrial waste so it needs to be removed. One way to reduce these heavy metals is to use activated carbon. Various types of organic materials and agricultural waste can be made into activated carbon.. One of the agricultural wastes that has great potential as activated carbon is salak seeds. This research processed salak seeds into activated carbon and modified them into Magnetic Activated Carbon (MAC). The research aims to obtain: 1) the best operating conditions for activated carbon production and MAC; 2) characteristics of activated carbon and MAC; 3) % removal of Pb(II) from liquid waste with MAC; 4) isotherm adsorption equation Pb(II) by MAC; 5) the kinetics equation of Pb(II) adsorption by MAC. The research method is to make activated carbon by carbonization, chemical and physical activation. The chemical activator used is a mixture of phosphoric acid - hydrochloric acid with a composition (1: 1). The next step is to make a MAC from activated carbon. Activated carbon characteristics were tested using the BET, SEM, EDX, and ASTM standard proximate tests. The results showed that activated carbon met SNI standards with iodine number 1230.93-1256.31 mg/g, surface area 539.147 m²/g, pore volume 44.0262-112.5906 cc/g. MAC contains 1% water, 21.88% volatile matter, 38% ash, 39.12% fixed carbon, and 1243.62 mg/g iodine number. Further findings show that the adsorption isotherm equation is best using the Freundlich equation. The Freundlich equation constants n = 1.3530 and KF = 34.634 mg/g with R² = 0.913, while the Langmuir equations b = 0.7442 L/mg and qm = 78.125 mg/g with R² = 0.6692. The Pb(II) adsorption kinetics test by MAC showed pseudo-2nd order adsorption kinetics with the constant k² = 0.2737 g/mg.min and R² = 1. [ABSTRACT FROM AUTHOR]

Lead (Pb(II)) is a pervasive heavy metal toxin with many well-established negative effects on human health. Lead toxicity arises from cumulative, repeated environmental exposures. Thus, prophylactic strategies to protect against the bioaccumulation of lead could reduce lead-associated human pathologies. Here we show that DNA and RNA aptamers protect C. elegans from toxic phenotypes caused by lead. Reproductive toxicity, as measured by brood size assays, is prevented by co-feeding of animals with DNA or RNA aptamers. Similarly, lead-induced neurotoxicity, measured by behavioral assays, are also normalized by aptamer feeding. Further, cultured human HEK293 and primary murine osteoblasts are protected from lead toxicity by transfection with DNA aptamers. The osteogenic development, which is decreased by lead exposure, is maintained by prior transfection of lead-binding DNA aptamers. Aptamers may be an effective strategy for the protection of human health in the face of increasing environmental toxicants. • Lead toxicity remains a pervasive public health problem, with limited interventions available. • Aptamers are short single-stranded nucleic acids that bind targets including proteins, small molecules, and ions. • Lead-binding aptamers applied to C. elegans protect the animals from lead-induced reproductive toxicity and neurotoxicity. • Upon transfection, DNA aptamers protect primary osteoblasts from lead toxicity. • The study represents the first demonstration of the use of an aptamer as a prophylactic to an environmental pollutant. [ABSTRACT FROM AUTHOR]

The present study investigated the capability of cassava peel (Manihot Esculenta Crantz) in Pb(II) and Cr(VI) removal. The comparative study was conducted using batch method observing some parameters. The results indicated that the optimum adsorption of Pb(II) occurred at pH 5, initial concentration of 1000 mg/L, and contact time of 50 min. On the other hand, the optimal adsorption of Cr(VI) was achieved at pH 2, initial concentration of 1200 mg/L, and contact time of 70 min. The adsorption isotherms of both metals tended to follow the Langmuir model, while the adsorption kinetics suited to pseudo-second-order model. Thermodynamic parameters indicated that the adsorption process was spontaneous (ΔG° negative), endothermic (ΔH° positive), and exhibited surface dispersion on the biosorbent (ΔS° positive). Characterization using Fourier Transform Infrared (FTIR), X-Ray Fluorescence (XRF), Scanning Electron Microscopy (SEM), and Thermogravimetry (TGA) provided evidence of both physical and chemical adsorption. The adsorption capacity of cassava peel was also tested on samples collected approximately 30 m from the bay shoreline, resulting in a removal percentage of 94.67% for Pb(II) and 82.28% for Cr(VI) under optimal pH and contact time conditions. [ABSTRACT FROM AUTHOR]

The purpose of this study is to determine how well activated carbon made from kluwak shell (Pangium edule Reinw) works as an adsorbent to remove Pb(II) and Cu(II) heavy metal ions from wastewater used in laboratories. Kluwak shell was selected as an agricultural waste material due to its high carbon content, which makes it a promising material for activated carbon that can lower Pb(II) and Cu(II) heavy metal levels. Finding the ideal contact time, pH, and adsorption capacity as well as the kinetics and adsorption isotherm model are the main goals of this study. Using 25% KOH for carbonization and chemical activation, Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM), and Surface Area Analyzer (SAA) for characterization are some of the research methods used. FTIR results showed the presence of O-H, C-H, C = C and C-O functional groups, while SEM showed more open pores after activation. SAA analysis indicated an activated carbon surface area of 3.11 m²/g, pore volume of 0.006 cm³/g, and pore diameter of 4.08 nm, categorized as mesoporous. The optimum condition for adsorption of Pb(II) ions is at pH 5 with contact time of 10 minutes and adsorption capacity of 21.83 mg/g. As for Cu(II) ions, the optimum condition is at pH 4 with a contact time of 20 minutes and adsorption capacity of 10.82 mg/g. The adsorption of metal ions is in accordance with the Langmuir isotherm model and pseudo second-order kinetics. The adsorption effectiveness of Pb(II) and Cu(II) ions from laboratory wastewater was 1.69 mg/g and 1.73 mg/g. It is concluded that activated kluwak shell can be used as Pb(II) and Cu(II) metal adsorbent. [ABSTRACT FROM AUTHOR]

Fungal biomass is as a cost-effective and sustainable biosorbent utilized in both active and inactive forms. This study investigated the efficacy of inactivated and dried biomass of Fusarium sp. in adsorbing Ni2+ and Pb2+ from aqueous solutions. The strain underwent sequential cultivation and was recovered by filtration. Then, the biomass was dried in an oven at 80 ± 2 °C and sieved using a 0.1-cm mesh. The biosorbent was thoroughly characterized, including BET surface area analysis, morphology examination (SEM), chemical composition (XRF and FT-IR), thermal behavior (TGA), and surface charge determination (pH-PZC and zeta potential). The biosorption mechanism was elucidated by fitting equilibrium models of kinetics, isotherm, and thermodynamic to the data. The biosorbent exhibited a neutral charge, a rough surface, a relatively modest surface area, appropriate functional groups for adsorption, and thermal stability above 200 °C. Optimal biosorption was achieved at 25 ± 2 °C, using 0.05 g of adsorbent per 50 mL of metallic ion solution at initial concentrations ranging from 0.5 to 2.0 mg L−1 and at pH 4.5 for Pb2+ and Ni2+. Biosorption equilibrium was achieved after 240 min for Ni2+ and 1440 min for Pb2+. The process was spontaneous, mainly through chemisorption, in monolayer for Ni2+ and multilayer for Pb2+, with efficiencies of over 85% for both metallic ion removal. These findings underscore the potential of inactive and dry Fusarium sp. biomass (IDFB) as a promising material for the biosorption of Ni2+ and Pb2+. [ABSTRACT FROM AUTHOR]

This study synthesized biochar through a one-pot pyrolysis process using IALG as the raw material. The physicochemical properties of the resulting biochar (IALG-BC) were characterized and compared with those of biochar derived from acid-treated lignin with the ash component removed (A-IALG-BC). This study further investigated the adsorption performances and mechanisms of these two lignin-based biochars for Pb(II). The results revealed that the high ash content in IALG, primarily composed of Na, acts as an effective catalyst during pyrolysis, reducing the activation energy and promoting the development of the pore structure in the resulting biochar (IALG-BC). Moreover, after pyrolysis, Na-related minerals transformed into particulate matter sized between 80 and 150 nm, which served as active adsorption sites for the efficient immobilization of Pb(II). Adsorption results demonstrated that IALG-BC exhibited a significantly superior adsorption performance for Pb(II) compared to that of A-IALG-BC. The theoretical maximum adsorption capacity of IALG-BC for Pb(II), derived from the Langmuir model, was determined to be 809.09 mg/g, approximately 40 times that of A-IALG-BC. Additionally, the adsorption equilibrium for Pb(II) with IALG-BC was reached within approximately 0.5 h, whereas A-IALG-BC required more than 2 h. These findings demonstrate that the presence of inorganic mineral components in IALG plays a crucial role in its resource utilization. [ABSTRACT FROM AUTHOR]

Abstract A novel chelating adsorbent based on (3-iminodiacetic acid) propyltriethoxysilane graphene oxide (IAT-GO) has been developed, showing exceptional promise for capturing lead. IAT-GO is made by combining a high-surface-area graphene oxide with a specially designed chelating ligand, which can selectively and efficiently remove lead. The synthesis of IAT-GO involves a two-step progression. In the first step, covalent bonds form between graphene oxide and (3-aminopropyl)-triethoxysilane (AT) through hydrolysis, condensation, and epoxide ring opening reactions. In the second step, nucleophilic substitution reactions occur between the primary amines and chloroacetic acid (CAA). A comprehensive suite of characterization techniques, including XPS, UV–Vis, XRD, Raman, FTIR, TEM, and SEM, provides detailed insights into the IAT-GO adsorbent's chemical composition and physical form, elucidating its intricate structure and morphology. Optimizing the experimental conditions for using the adsorbent material to remove Pb(II) ions from contaminated water revealed a maximum adsorption capacity of 124.0 mg/g at pH 5 and 30 min. The IAT-GO displays high selectivity for Pb(II) in a mixture of six metal ions containing 100 ppm of each one. Moreover, the IAT-GO shows 100% removal of Pb(II) for concentrations lower than 50 ppm. The excellent fit of the experimental data with the Langmuir adsorption isotherm and pseudo-second-order kinetic models (R2 > 99%) indicates that Pb(II) ion uptake onto the IAT-GO surface occurs via the monolayer formation of mercury ions. IAT-GO demonstrates exceptional potential as an innovative adsorbent for lead-contaminated water. Nitric acid (0.4 M) effectively regenerates the material, while its reusability remains impressive even after five cycles (> 97% removal efficiency). Therefore, this study highlights the development of a groundbreaking material, IAT-GO, with exceptional potential for remediating lead-contaminated water. Its high efficiency, selectivity, reusability, and cost-effectiveness make it a promising candidate for real-world applications.

Abstract This study describes a novel adsorbent with a multidentate ligand that was facilely fabricated by covalently bonding 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole on graphene oxide (AHMT-PRGO). The AHMT-PRGO nano-adsorbent was used for the effective removal of Hg(II), Pb(II), and Cr(VI) from wastewater. The AHMT-PRGO nano-adsorbent was synthesized by a nucleophilic substitution reaction between GO acyl chloride and AHMT chelating ligand in the presence of tetrabutyl-ammonium bromide as a catalyst. The successful modifications were confirmed via several spectroscopic and electron microscopy instrumentations including UV–Vis, FTIR, Raman, XRD, XPS, SEM, and TEM. The maximum adsorption capacities of Hg(II), Cr(VI), and Pb(II) on the AHMT-PRGO nano-adsorbent were 370.0, 136.2, and 109.6 mg/g, respectively, exceeding those of most previously reported adsorbents. Additionally, the equilibrium contact times for Hg(II), Pb(II), and Cr(VI) were 60, 30, and 400 min, respectively. In a mixture of nine heavy metal ions containing 250 ppm of each ion, the AHMT-PRGO nano-adsorbent exhibited high selectivity for Hg(II) ions. Furthermore, the AHMT-PRGO nano-adsorbent showed high stability over five adsorption–desorption cycles. Additionally, the AHMT-PRGO nano-adsorbent was successfully applied to remove heavy metal ions from real water samples. The novelty of AHMT-PRGO lies in the combination of a multidentate ligand for strong and selective binding with the high surface area and stability offered by covalently bonded graphene oxide. This combination offers potential advantages over traditional adsorbents in terms of adsorption capacity, selectivity, and reusability.

Copper and lead ions are the most important toxic metals that cause significant environmental and health problems. In this study, we focused on the development of a very cost-effective and environmentally friendly (renewable) remediation technique using vine sprout, an industrial beer waste and readily available agricultural biowaste. In this study, it was aimed to remove the copper and lead that enter the body for various reasons orally, from the simulated stomach medium (SSM) by adsorption in order to reduce their toxic effects on human health. Activated carbon (ACVS) obtained from vine shoots was used as adsorbent. By preparing an artificial stomach medium, the most suitable adsorption parameters (pH, time, mixing speed, amount of adsorbent, and the effect of other components) were examined in the batch system. Equilibrium adsorption data was interpreted using the Langmuir model. The initial Cu(II) and Pb(II) ion concentrations were 10 mg/L and the adsorbent amount was 0.3 g, and the maximum adsorption efficiency of Cu(II) and Pb(II) ions was 100% in the pH 3.5–6.5 range. The performance variables of the adsorbent used were compared with the performance variables of the commercial activated carbon (CAC) used in the emergency response. It was determined that the adsorbent used was more effective in removing copper and lead. [ABSTRACT FROM AUTHOR]

A novel chelating adsorbent based on (3-iminodiacetic acid) propyltriethoxysilane graphene oxide (IAT-GO) has been developed, showing exceptional promise for capturing lead. IAT-GO is made by combining a high-surface-area graphene oxide with a specially designed chelating ligand, which can selectively and efficiently remove lead. The synthesis of IAT-GO involves a two-step progression. In the first step, covalent bonds form between graphene oxide and (3-aminopropyl)-triethoxysilane (AT) through hydrolysis, condensation, and epoxide ring opening reactions. In the second step, nucleophilic substitution reactions occur between the primary amines and chloroacetic acid (CAA). A comprehensive suite of characterization techniques, including XPS, UV–Vis, XRD, Raman, FTIR, TEM, and SEM, provides detailed insights into the IAT-GO adsorbent's chemical composition and physical form, elucidating its intricate structure and morphology. Optimizing the experimental conditions for using the adsorbent material to remove Pb(II) ions from contaminated water revealed a maximum adsorption capacity of 124.0 mg/g at pH 5 and 30 min. The IAT-GO displays high selectivity for Pb(II) in a mixture of six metal ions containing 100 ppm of each one. Moreover, the IAT-GO shows 100% removal of Pb(II) for concentrations lower than 50 ppm. The excellent fit of the experimental data with the Langmuir adsorption isotherm and pseudo-second-order kinetic models (R2 > 99%) indicates that Pb(II) ion uptake onto the IAT-GO surface occurs via the monolayer formation of mercury ions. IAT-GO demonstrates exceptional potential as an innovative adsorbent for lead-contaminated water. Nitric acid (0.4 M) effectively regenerates the material, while its reusability remains impressive even after five cycles (> 97% removal efficiency). Therefore, this study highlights the development of a groundbreaking material, IAT-GO, with exceptional potential for remediating lead-contaminated water. Its high efficiency, selectivity, reusability, and cost-effectiveness make it a promising candidate for real-world applications. [ABSTRACT FROM AUTHOR]

This study describes a novel adsorbent with a multidentate ligand that was facilely fabricated by covalently bonding 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole on graphene oxide (AHMT-PRGO). The AHMT-PRGO nano-adsorbent was used for the effective removal of Hg(II), Pb(II), and Cr(VI) from wastewater. The AHMT-PRGO nano-adsorbent was synthesized by a nucleophilic substitution reaction between GO acyl chloride and AHMT chelating ligand in the presence of tetrabutyl-ammonium bromide as a catalyst. The successful modifications were confirmed via several spectroscopic and electron microscopy instrumentations including UV–Vis, FTIR, Raman, XRD, XPS, SEM, and TEM. The maximum adsorption capacities of Hg(II), Cr(VI), and Pb(II) on the AHMT-PRGO nano-adsorbent were 370.0, 136.2, and 109.6 mg/g, respectively, exceeding those of most previously reported adsorbents. Additionally, the equilibrium contact times for Hg(II), Pb(II), and Cr(VI) were 60, 30, and 400 min, respectively. In a mixture of nine heavy metal ions containing 250 ppm of each ion, the AHMT-PRGO nano-adsorbent exhibited high selectivity for Hg(II) ions. Furthermore, the AHMT-PRGO nano-adsorbent showed high stability over five adsorption–desorption cycles. Additionally, the AHMT-PRGO nano-adsorbent was successfully applied to remove heavy metal ions from real water samples. The novelty of AHMT-PRGO lies in the combination of a multidentate ligand for strong and selective binding with the high surface area and stability offered by covalently bonded graphene oxide. This combination offers potential advantages over traditional adsorbents in terms of adsorption capacity, selectivity, and reusability. [ABSTRACT FROM AUTHOR]

Heavy metal pollution and organic wastewater treatment have attracted extensive attention of researchers. Adsorption method is widely used in wastewater treatment because of its low price and high efficiency. As a natural, cheap biomass material, bamboo powder is of great significance to develop it into an economical and efficient biochar for wastewater treatment. A new type of ball-milled biochar (BMBC) adsorbent was prepared by pyrolysis of bamboo powder under an inert atmosphere, activated with sodium hydroxide solution and ball milling. The specific surface area of BMBC increased from 29.21 to 60.49 m2/g, and the carboxyl and hydroxyl groups on the pyrolyzed carbon surface also obviously increased after ball milling. The results of bath adsorption experiments showed that BMBC exhibited excellent adsorption capacity towards both Pb(II) (170.52 mg/g) and methylene blue (MB, 419.11 mg/g) at 308 K. Based on a systematic study on the effect of various working conditions (including concentration, temperature, pH value, and ionic strength), it was demonstrated that pseudo-second-order kinetic equation might match the adsorption process (R2 > 0.9934) and Langmuir model (R2 > 0.9924); adsorptions were thermodynamically endothermic and occurred spontaneously. The ball milled alkalization-modified bamboo biochar can potentially be applied to remove heavy metal and cationic pollutants from wastewater. [ABSTRACT FROM AUTHOR]

To develop cost-effective heavy metal adsorbents, we employed water-soluble lignin from black liquor to modify activated attapulgite, resulting in the creation of a novel adsorbent called Lignin-modified attapulgite (LATP). In this study, scanning electron microscopy and Fourier transform infrared spectrometer techniques were utilized to characterize the structural details of LATP. The results revealed that lignin occupies the micropores of attapulgite, while additional functional groups are present on the attapulgite surface. We conducted adsorption tests using LATP to remove five types of heavy metal ions (Cd2+, Pb2+, Zn2+, Mn2+, Cu2+), and it was found that LATP exhibited greater removal mass and binding strength for Pb(II) compared to the other ions. For further investigation, batch experiments were performed to evaluate the adsorptive kinetics, isotherms, and thermodynamics of Pb2+ removal from aqueous solutions using LATP. The results indicated that the adsorption capacity of Pb(II) on LATP decreased with decreasing pH, while the presence of Na+ had no effect on adsorption. The adsorption process reached equilibrium rapidly, and the Langmuir adsorption capacities increased with temperature, measuring 286.40 mg/g, 315.51 mg/g, and 349.70 mg/g at 298 K, 308 K, and 318 K, respectively. Thermodynamic analysis revealed positive values for ΔH0 and ΔS0, indicating an endothermic and spontaneous adsorption process. Furthermore, ΔG0 exhibited negative values, confirming the spontaneous nature of the adsorption. Consequently, LATP demonstrates great potential as an effective adsorbent for the removal of Pb(II). Therefore, LATP shows great potential as an effective adsorbent for the removal of Pb(II) from natural water environments, contributing to the sustainable development of man and nature. [ABSTRACT FROM AUTHOR]

Activated carbon nonwoven nanofibres (ACNN) mat derived from polyacrylonitrile was manufactured through the electrospinning method followed by thermal treatment steps. The ACNN ability to adsorb Pb(II) from a liquid solution was evaluated. The fabricated ACNN was characterized using scanning electron microscope, Fourier-transform infrared spectroscopy, and Brunauer-Emmett-Teller method. The resulting ACNN exhibited nanofibres with a diameter of 530 nm and a surface area of 550 m2/g. Various adsorption experiments were performed in batch scale to study the impact of factors like contact time, initial Pb(II) ions concentration, and pH. At pH 5, ACNN achieved a removal efficiency of 98% of Pb(II). The equilibrium data for Pb(II) ions was analysed using the Freundlich and Langmuir isotherm models. Both kinetic models (pseudo-first-order and pseudo-second-order) and isotherm models were tested. Results revealed that the Langmuir model accurately described the adsorption isotherm of Pb(II) with a maximum capacity of 15.72 mg/g. Data analysis suggested that the pseudo-second-order model better represented the kinetic adsorption behaviour of Pb(II). [ABSTRACT FROM AUTHOR]

Using peanut shells, a sustainable agricultural waste product, as its raw material, the acid group-modified biochar (AMBC) was prepared through phosphoric acid activation, partial carbonization, and concentrated sulfuric acid sulfonation for efficient removal of lead ion from aqueous solutions. Characterization techniques such as N2 isothermal adsorption–desorption, SEM, XRD, FT-IR, TG-DTA, and acid–base titration were utilized to fully understand the properties of the AMBC. It was found that there were high densities of acidic oxygen-containing functional groups (-SO3H, -COOH, Ph-OH) on the surface of the AMBC. The optimal adsorption performance of the AMBC for Pb(II) in water occurred when the initial concentration of Pb(II) was 100 mg/L, the pH was 5, the dosage of the adsorbent was 0.5 g/L, and the contact time was 120 min. Under the optimal conditions, the removal ratio of Pb(II) was 76.0%, with an adsorption capacity of 148.6 mg/g. This performance far surpassed that of its activated carbon precursor, which achieved a removal ratio of 39.7% and an adsorption capacity of 83.1 mg/g. The superior adsorption performance of AMBC can be caused by the high content of acidic oxygen-containing functional groups on its surface. These functional groups facilitate the strong binding between AMBC and Pb(II), enabling effective removal from water solutions. [ABSTRACT FROM AUTHOR]

In the present research, the presence of water hyacinth (Eichhornia crassipes) on the surface of the San Jose Dam located in the city of San Luis Potosi, S.L.P, Mexico, was monitored and mapped. The monitoring was conducted for 2 years (2018–2020) with remote sensing data from OLI Landsat 8 sensors, based on the normalized difference vegetation index (NDVI). The results demonstrated the capability and accuracy of this method, where it was observed that the aboveground cover area, proliferation, and distribution of water hyacinth are influenced by climatic and anthropogenic factors during the four seasons of the year. As part of a sustainable environmental control of this invasive species, the use of water hyacinth (WH) root (RO), stem (ST), and leaf (LE) components as adsorbent material for Pb(II) present in aqueous solution was proposed. The maximum adsorption capacity was observed at pH 5 and 25 °C and was 107.3, 136.8, and 120.8 mg g−1 for RO, ST, and LE, respectively. The physicochemical characterization of WH consisted of scanning electron microscopy (SEM), N2 physisorption, infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), charge distribution, and zero charge point (pHPZC). Due to the chemical nature of WH, several Pb(II) adsorption mechanisms were proposed such as electrostatic attractions, ion exchange, microprecipitation, and π-cation. [ABSTRACT FROM AUTHOR]

The electrochemical behavior of PbCl2 in NaCl–KCl molten salt on graphite and molybdenum electrodes was investigated using cyclic voltammetry, square wave voltammetry, chronopotentiometry, and open circuit chronopotentiometry at 750°C. A pair of redox peaks for Pb(II)/Pb was observed from the cyclic voltammetry (CV) results, with cathodic peak potentials of –0.16 and –0.2 V at the molybdenum and graphite electrodes, respectively. It was also confirmed that the reduction of Pb(II)/Pb was a one-step reduction process with a two-electron transfer and a quasi-reversible process. Square wave voltammetry (SWV) was also used to confirm the accuracy of the CV results further. The diffusion coefficients of Pb(II) ions on molybdenum and graphite electrodes were calculated using the Berzins-Delahay equation, which were 3.85 × 10–5 and 7.42 × 10–5 cm2 s–1, respectively. Similarly, the diffusion coefficients were also calculated using the Sand equation, which were 2.89 × 10–5 and 4.55 × 10–5 cm2 s–1, respectively. In addition, the deposition and dissolution behavior of Pb(II) on molybdenum and graphite electrodes were further investigated with chronopotentiometry (CP) and open circuit chronopotentiometry (OCP), respectively, and the results obtained were in agreement with the CV and SWV results. This study lays a foundation for the recycling of secondary Pb resources and the preparation of Ti–Pb alloys by electrodeposition method in molten salt. [ABSTRACT FROM AUTHOR]

This research studies on the visible photocatalytic improvement and separable ability of TiO2 by Fe doping and Fe3O4 magnetizing from iron rusty waste. The doping and magnetizing were performed by hydrothermal and precipitation methods, respectively. The Fe doped TiO2 (TiO2–Fe) prepared was magnetized with Fe3O4 having fraction of 33.3 wt%. The research results assign that from the characterization of the prepared photocatalysts by means of X-ray diffraction (XRD), diffuse reflectance UV–visible (DRUV–Visible), and Fourier Transform infrared (FTIR), the Fe doped and Fe3O4 precipitated into TiO2 to form TiO2–Fe/Fe3O4 photocatalyst has been successfully synthesized. Furthermore, the doping and magnetizing have considerably enhanced the activity of TiO2–Fe/Fe3O4 photocatalyst under visible light and given good magnetic separable properties. The highest photo-oxidation of Pb(II) 10 mg/L in 100 mL of the solution can be obtained by applying 50 mg weight of TiO2–Fe/Fe3O4 photocatalyst, solution pH of 6 and 60 min of the reaction time, reaching 83% efficiency. The photo-oxidation of Pb(II) is supposed to transform the toxic Pb (II) into a handleable PbO2 with less hazardous properties. Hence, circular environmental management would be expected for this study from utilizing the priceless waste to enhance material properties in the reducing the toxic contaminant. [ABSTRACT FROM AUTHOR]

The adsorption property of the costless green cellulose acetate (CA) was boosted by the dual modifications: inner modification by incorporating carboxylated graphene oxide (COOH-GO) into the CA spheres and outer modification by the surface modification of the COOH-GO@CA spheres by iminodiacetic acid (IDA) for removing Pb(II). The adsorption experiments of the Pb(II) proceeded in a batch mode to evaluate the adsorption property of the COOH-GO@CA@IDA spheres. The maximal Pb(II) adsorption capacity attained 613.30 mg/g within 90 min at pH = 5. The removal of Pb(II) reached its equilibrium within 20 min, and the removal % was almost 100% after 30 min at the low Pb(II) concentration. The Pb(II) adsorption mechanism was proposed according to the kinetics and isotherms studies; in addition, the zeta potential (ZP) measurements and X-ray Photoelectron Spectroscopy (XPS) analysis defined the adsorption pathways. By comparing the XPS spectra of the authentic and used COOH-GO@CA@IDA, it was deduced that the contributed chemical adsorption pathways are Lewis acid–base, precipitation, and complexation. The zeta potential (ZP) measurements demonstrated the electrostatic interaction participation in adsorbing the cationic Pb(II) species onto the negatively charged spheres (ZP = 14.2 mV at pH = 5). The unique channel-like pores of the COOH-GO@CA@IDA spheres suggested the pore-filling mechanism of Pb(II). The promising adsorption results and the superb recyclability character of COOH-GO@CA@IDA enable it to extend of the bench scale to the industrial scale. [ABSTRACT FROM AUTHOR]

In this study, eco-friendly casein-copper hybrid nanoflowers (CAS-Cu HNFs) were synthesised and their applicability for the removal of Pb(II) and Cd(II) ions was investigated. Hybrid nanoflowers were synthesised by adding CuSO4 solution on casein in PBS medium. According to the evaluation of SEM images, regular nanoflower structures were obtained after the addition of 40 µL of 100 mM CuSO4 and 12 h incubation. Characterisation studies were performed by XRD, SEM-EDX, FTIR and TGA. The effects of contact time, pH, temperature and heavy metal ion concentration on the adsorption performance were investigated. Optimum adsorption was achieved at 60 min contact time and 35 and 30 °C for Pb(II) and Cd(II) ions, respectively. The performance of CAS-Cu HNFs was evaluated by linear and non-linear forms of adsorption isotherms and adsorption kinetics, respectively. The linear Langmuir isotherm model showed compatibility and the maximum adsorption capacity was found to be 769.23 and 156.25 mg/g for Pb(II) and Cd(II) ions, respectively. CAS-Cu HNFs has great potential as an eco-friendly, nanoscale, flower-like, organic–inorganic hybrid nano-flower adsorbent for the effective removal of Pb(II) and Cd(II) ions from aqueous solutions. [ABSTRACT FROM AUTHOR]

The biosorption of Pb(II) from an aqueous environment was studied using a mixed biofilm of microalgal biomass (Chlorella vulgaris) and natural pectin. A gas sorption analyzer, Fourier transform infrared spectrometer, field emission scanning electron microscope, point of zero charge determination, and texture analyzer were used for the adsorbent's characterization. Various sorption parameters such as contact time, initial pH, initial metal concentration and temperature were studied. The results were also used to conduct isotherm and kinetic studies. Subsequently, the second-order polynomial model following the response surface methodology was obtained with an R2 of 0.9941 indicating acceptable accuracy. Under the following condition: an initial pH of 4.27, an initial metal concentration of 300 mg/L, and a temperature of 55.2 °C, a maximum Pb(II) uptake of 121.89 mg/g was observed. The results show that the developed composite biofilm can effectively remove Pb(II) ions from contaminated water. [ABSTRACT FROM AUTHOR]

To improve the removal capacity of rice straw biochar for heavy metals in acidic mine wastewater, magnesium-modified rice straw biochar (MBC) was prepared by impregnation-pyrolysis method. The effects of impregnation ratio, solution pH,adsorption time,and initial concentration on the removal of Cd(II) and Pb(II) from acid mine wastewater by MBC were investigated through batch adsorption experiments, and the features of MBC before and after adsorption were analyzed by characterisation techniques to explore the potential adsorption mechanisms. The results showed that the MBC prepared by impregnation-pyrolysis possessed a well-developed pore structure. The adsorption experiments showed that the removal efficiency for 10 mg/L of Pb(II) and Cd(II) by MBC reached the optimum values of 93. 58% and 97. 95% at impregnation ratio 2 : 1 and solution pH 5. 0 respectively. The removal process of Cd( II) and Pb(II) by MBC was consistent with the pseudo second order kinetic model and Langmuir adsorption isotherm model. According to the Langmuir model,the maximum adsorption capacities of MBC for Cd(II) and Pb(II) were 90. 45 mg/g and 138. 50 mg/g, respectively. FTIR and XRD analyses showed that the removal mechanism of Cd (II) and Pb (II) by MBC contained complexation, co-precipitation, ion exchange, and electrostatic interaction. After five regenerations, the removal efficiency of Cd(II) and Pb(II) by MBC was maintained at 85. 62% and 80. 16%, respectively. The above results indicated that MBC had great potential for treating acid mine wastewater containing Cd(II) and Pb(II). [ABSTRACT FROM AUTHOR]

Some heavy metals such as Pb, Cd, Hg and As are extremely hazardous to the human beings because of their non-biodegradable nature even at very low levels of exposure. Besides the standard methods such as Inductively Coupled Plasma (ICP)-Mass Spectrometry and ICP-Optical Emission Spectrometry, the other methods with fast, accurate and cheap requirements also need to be developed to detect these toxic heavy metals ions in aquatic sources. Recently the application of porous materials in the anodic stripping voltammetry has gained a great attention owing to high selectivity, sensitive and low cost. In the present study, a glassy carbon electrode (GCE) modified by ZnO- electrochemically reduced graphene oxide (ZnO/ErGO) was used for the electrochemical detection of Pd(II) and Cd(II). It is found that the surface area of ZnO/ErGO-GCE is 0.130 cm2 much larger than that of the bare GCE (0.083 cm2).The charge transfer resistance decreases significantly from 3212 Ω for the bare GCE to 924 Ω for ZnO/ErGO-GCE. These results manifest a fast electron transfer ratio of kinetics for the ZnO/ErGO-modified electrode. ZnO/ErGO-GCE exhibits excellent electrochemical performance towards the detection of Pb(II) and Cd(II) compared with ErGO-GCE and bare GCE. The peak current has a linear relationship with the Cd(II) and Pb(II) concentration in the 2.5–200 µM range. The limit of detection for Cd(II) and Pb(II) is 1.69 and 0.45 ppb, respectively. In addition, the electrochemical sensor exhibits excellent selectivity, stability, and repeatability in experimental studies, and it opens up great potential for detecting a trace amount of metals. [ABSTRACT FROM AUTHOR]

Defective NH 2 -UiO-66 adsorbent (named as NH 2 -UiO-66-SD) was successfully fabricated via post-synthesis method with the aid of both sodium carbonate anhydrous (Na 2 CO 3) and diethylenetriaminepentaacetic acid (DTPA), in which the defective structure was confirmed by various characterizations. The as-obtained defective NH 2 -UiO-66-SD exhibited outstanding Pb(II) sorption capacity (172.21 ​mg ​g−1) and rapid diffusion rate (29.87 ​mg ​g−1 min−0.5) at room temperature with optimal pH being 5.47. The Pb(II) sorption behavior was conformed to pseudo-second-order kinetics and Langmuir model, demonstrating that the chemical sorption of the monolayer played a dominant model. As well, the thermodynamic parameters like standard Gibbs free energy change Δ G o (−31.21 ​kJ ​mol−1), standard enthalpy change Δ H o (12.79 ​kJ−1 ​mol−1) and standard entropy change Δ S o (146.73 ​J ​mol−1 ​K−1) revealed that the Pb(II) sorption process of NH 2 -UiO-66-SD was spontaneous, endothermic and disordered. Furthermore, the NH 2 -UiO-66-SD exhibited desirable desorption and recirculation performances (removal efficiencies >85 ​% in 5 runs) with ideal stability. Moreover, the Pb(II) sorption mechanism of NH 2 -UiO-66-SD mainly included the electrostatic attractions and coordinative interactions. Overall, this work offered an intriguing method of fabricating defective NH 2 -UiO-66 adsorbent, which vastly enhanced adsorption efficiency for toxic metal ions elimination from wastewater. [Display omitted] • Defective NH 2 -UiO-66 was successfully fabricated via Na 2 CO 3 and DTPA. • Exceptional Pb(II) adsorption capacity (172.21 ​mg ​g−1) was achieved. • The type of defect included missing linkers and missing Zr–O clusters. • The possible adsorption mechanism for NH 2 -UiO-66-SD toward Pb(II) were proposed. [ABSTRACT FROM AUTHOR]

Industrial processes are the main source of Pb(II) contamination of natural water bodies. Pb(II) is a non-biodegradable heavy metal and carcinogen. The recent study explored the ability of citric acid-modified-kepok banana peel (CA-BP) to remove Pb(II) from an aqueous solution using the batch method. The adsorption capacity of kepok banana peel (BP) was also investigated for comparison. The optimum conditions for Pb(II) removal using kepok banana peel were achieved at pH 5, initial concentration of 600 mg l-1, contact time of 75 min, and agitation speed of 100 rpm, with an adsorption capacity of 36.478 mg g-1. Meanwhile, the adsorption capacity of citric acid modified-kepok banana peel was 64.088 mg g-1, which was reached at pH 5, initial concentration of 850 mg l-1, contact time of 75 min, and agitation speed of 150 rpm. The adsorption of Pb(II) onto both sorbents followed the Langmuir isotherm model and pseudo-second-order model, indicating monolayer adsorption with chemical interaction as a rate-limiting step. A Fourier Transform Infra-Red (FTIR) analysis was conducted to identify the functional groups present in the biosorbent and demonstrate a change in the wave number. The surface morphology of the biosorbent was examined using Scanning Electron Microscopy (SEM) before and after the absorption of Pb2+ metal ions. The objective of Energy Dispersive X-ray (EDX) is to quantify the elemental composition of the biosorbent derived from the surface of the kepok banana peel. An X-ray fluorescence (XRF) analysis was conducted to determine the chemical composition of the surface of the kepok banana peel biosorbent. Thermogravimetric Analysis (TGA) was conducted to observe the decrease in mass of the biosorbent as the temperature increased. [ABSTRACT FROM AUTHOR]

• BW has strong acid resistance (pH ≥ 1). • BW selectively separates lead from complex heavy metal solutions. • The selective immobilization is due to its specific composite structure. The development of bio-adsorbents with highly selective immobilization properties for specific heavy metals is a great challenge, but has important application value. Biogenic whewellite (BW) with high selectivity for Pb(II) was synthesized by mineral microbial transformation. The selective immobilization properties and mechanism of BW for Pb(II) were analyzed by combining mineral characterization technology and batch adsorption research methods. The results indicated that BW can efficiently and selectively immobilize Pb(II) in single or composite heavy metal adsorption solutions, and the immobilized Pb(II) is difficult to desorb. BW undergoes monolayer adsorption on Pb(II), Q max ≈ 1073.17 mg/g. The immobilization of Pb(II) by BW is a physico-chemical adsorption process with spontaneous heat absorption and an accompanying increase in entropy. In addition, the sequestration of Pb(II) by BW remains around 756.99 mg/g even at pH = 1. The excellent selective immobilization properties of BW for Pb(II) are closely related to its smaller K sp , electrostatic repulsion effect, organic-inorganic composite structure, acid resistance and the formation of Pb(II) oxalate. This study provides beneficial information about the recycling of lead in acidic lead-containing wastewater and composite heavy metal contaminated water bodies. [Display omitted] [ABSTRACT FROM AUTHOR]

Toxic heavy metals are ubiquitous in the aquatic environment and show a significant danger to human health. Carbon nanotubes have been extensively used in treating the contamination of groundwater due to their porous multi-layer nature. Batch tests revealed that oxidized multiwalled carbon nanotubes (O-MWCNTS) offer better removal of Pb(II). The removal rate of Pb(II) was 90.15% at pH 6 within 24 h, which was ~58% more than that of Cd(II). The removal rate decreased to 55.59% for Pb(II) and to 16.68% for Cd(II) when the initial concentration of Pb(II)/Cd(II) ranged from 5 to 15 mg·g−1. The removal rate in the competitive tests was about 60.46% for Pb(II) and 9.70% for Cd(II). The Langmuir model offered better description of the adsorptive data for both ions. And the Qm of Pb(II) was 5.73 mg·g−1, which was 2.39 mg·g−1 more than that of Cd(II) in a single-icon system, while Qm was 7.11 mg·g−1 with Pb(II) and 0.78 mg·g−1 with Cd(II) in competitive water. And thermodynamic tests further indicated that the activating energy of Pb(II) and Cd(II) was 83.68 and 172.88 kJ·mol−1, respectively. Lead and cadmium adsorbed on the surface of O-MWCNTS are antagonistic in the competitive system. Based on XPS analyses, it was concluded that the absorbed lead/cadmium species on O-MWCNTS were (-COO)2Pb, (-COO)Pb(-O)/(-COO)2Cd, and (-COO)Cd(-O). Additionally, they offered theoretical evidence supporting the practicality of using nanocomposite membranes as a means to remove cadmium and lead. [ABSTRACT FROM AUTHOR]

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Nitrogen-doped mesoporous carbon（NMC） was synthesized using hard-template，and was characterized using specific surface area analyzer，transmission electron microscope，Fourier transform-infrared spectrometer and X-ray photoelectron spectroscopy. NMC was applied in the adsorption of Pb（Ⅱ） in two different tunnel construction wastewaters，and the effects of pH，reaction time on adsorption and its adsorption kinetics models and sorption isotherms were investigated. The results showed that the adsorption kinetics was best described by pseudo-second-order model，and its adsorption characteristics conformed to the Langmuir and Temkin model. According to the results of the experiments and characterization，Pb（Ⅱ） adsorption by NMC involved physisorption such as electrostatic interaction and pore diffusion and chemisorption like chelation with functional groups. The estimated maximum adsorption capacity based on Langmuir model was 493.5 mg/g and 603.9 mg/g，respectively for the two wastewaters. In addition，NMC could be regenerated and reused by treatment with HCl.

Chitosan-pectin gel beads (CPB) have high potential for removing heavy metals from food. This study aimed to improve their stability, recyclability, and adsorption capacity by modified CPB with gelatin (Gel) and carboxymethyl cellulose sodium (CMC). The structural characteristics of the modified CPBs were characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG), Zeta potential, scanning electron microscopy (SEM), pore size distribution analysis (BET), X-ray photoelectron spectroscopy (XPS), specific surface area analysis. The adsorption-resolution conditions of modified CPB were optimized, and their actual removal efficiency for Pb(II) in C-phycocyanin was evaluated. Results showed that CMC-modified CPB (CMC-CPB) had higher thermal stability, rougher and more porous surface, larger specific surface area (20.28±1.35 m2/g), lower zeta potential, stronger metal ion adsorption capacity, and higher regeneration efficiency compared with CPB and Gel-CPB. FTIR showed the functional group of CPB had significant difference after modification, and the main group in CPB were carboxyl, hydroxyl, and amino groups. TG analysis presented the thermal stability of CMC-CPB was higher than that of CPB and Gel-CPB. XPS analysis showed CMC-CPB had the strongest absorption peak for Pb(II). The optimal pH and temperature for the three adsorbents (CPB, Gel-CPB, and CMC-CPB) to remove Pb(II) were 6.0 and 60 ℃, respectively. The Pb(II) adsorption process of all three adsorbents fit the Langmuir isotherm model (R2=0.9543~0.9811) and the pseudo-second-order kinetic model (R2=0.9963~0.9991), and the adsorption process belonged to the monolayer chemical adsorption, involving the complexation of -COO, -OH, -CO-NH, and Pb(II). Based on the Langmuir model curve, the maximum adsorption capacity (qmax) of CMC-CPB for Pb(II) was 69.37 mg/g, significantly higher than that of Gel-CPB and CPB (P

The impact of Ba-modified peanut shell biochar (Ba-PSB) on Pb(II) removal was studied and BaCl2 was used as a modifier. It was shown that the PSB obtained at 750 °C had the best adsorption effect, and the Ba-PSB had a larger specific surface area and a good adsorption effect on Pb(II). At pH = 5, concentration was 400 mg/L, time was 14 h, and temperature was 55 °C, the loading amount of black peanut shell biochar (BPSB), red peanut shell biochar (RPSB), Ba-BPSB, and Ba-RPSB reached 128.050, 98.217, 379.330, and 364.910 mg/g, respectively. In addition, based on the non-linear fitting, it was found that the quasi-second-order kinetic model, and isothermal model could be applied to describe Pb(II) adsorption on PSB and Ba-PSB. The adsorption behavior of PSB unmodified and modified was a spontaneous process. Moreover, chemical modification of BPSB, RPSB, Ba-BPSB, and Ba-RPSB for hindering of –COOH and –OH groups revealed 81.81, 77.08, 86.90, and 83.65% removal of Pb(II), respectively, which was due to the participation of –COOH, while 17.61, 21.70, 12.77, and 15.06% was from –OH group, respectively. The increase of cation strength (Na+, K+, Ca2+, and Mg2+) will reduce the adsorption capacity of PSB for Pb(II). HIGHLIGHTS Ba-modified PSB was prepared and its adsorption property was examined.; The modification of PSB could greatly improve its loading amount for Pb(II).; The effect of –COOH and –OH groups from PSB on Pb(II) sorption was scrutinized.; Ba-modified PSB was an excellent green adsorbent for Pb(II) removal from water.;

Sintesis material imprinted ionic Pb(II) (SiO2-TMPDT-Pb-Imp) menggunakan natrium silikat dari abu sekam padi (Na­2SiO3(ASP)) telah berhasil dilakukan pada penelitian ini dengan memanfaatkan abu sekam padi sebagai sumber silika untuk pembuatan natrium silikat (Na­2SiO3(ASP)). Modifier yang digunakan adalah N1-(3-trimethoxysilylpropyl)diethylentriamine (TMPDT) dan ion logam Pb(II) berfungsi sebagai templat. Uji kapasitas adsorpsi SiO2‒TMPDT‒Pb‒Imp terhadap ion logam Pb(II) dilakukan pada variasi pH (1 ‒ 6) dan waktu kontak (0 ‒ 120) menit dengan sistem batch. Karakterisasi material SiO2‒TMPDT‒Pb-Imp dilakukan dengan menggunakan Fourier Transform Infrared (FTIR), Scanning Electron Microscope and Energy Dispersive X-ray (SEM-EDX), dan Surface Area Analyzer (SAA). Berdasarkan data FTIR dan SEM-EDX menunjukkan bahwa material SiO2‒TMPDT‒Pb‒Imp memiliki gugus silanol (Si‒OH); siloksan (Si‒O‒Si); alkana dan gugus amin dengan morfologi material yang halus serta terdapat unsur karbon (C) dan nitrogen (N) sebanyak 44,4% dan 8,3% secara berurutan. Hasil karakterisasi dengan SAA menunjukkan bahwa material SiO2‒TMPDT‒Pb‒Imp memiliki luas permukaan sebesar 7,418 m2/g, volume pori total sebesar 0,012 cc/g dan jari-jari pori sebesar 16,670 Å. Kondisi terbaik adsorpsi ion logam Pb(II) terjadi pada pH 5 dan waktu kontak 60 menit yang mengikuti model kinetika adsorpsi Pseudo Orde 2 dengan kapasitas adsorpsi sebesar 1,2418 mg/g. Utilization of Silica from Rice Husk Ash for Preparing Imprinted Ionic Materials as Pb(II) Metal Ion Adsorbent. Imprinted ionic Pb(II) (SiO2-TMPDT-Pb-Imp) material was synthesized using a solution of sodium silicate from rice husk ash (Na­2SiO3(RHA)) in this study using rice husk ash as a source of silica for sodium silicate (Na2SiO3(ASP)). The modifier used is N1-(3-trimethoxysilylpropyl) diethylenetriamine (TMPDT) and Pb(II) metal ion as a template. The SiO2‒TMPDT‒Pb‒Imp adsorption capacity of Pb(II) metal ion was performed on solution pH (1 ‒ 6) and contact time of (0 ‒ 120) minutes by the batch system. Material characterization was performed by Fourier Transform Infrared (FTIR), Scanning Electron Microscope and Energy Dispersive X-ray (SEM-EDX), and Surface Area Analyzer (SAA). Based on FTIR and SEM-EDX showed that SiO2‒TMPDT‒Pb‒Imp had a silanol group (Si‒OH), siloxane group (Si‒O‒Si), alkane and amine group with finer material morphology and presence of carbon (C) and nitrogen (N) element of 44.4% and 8.3% respectively. SAA characterization indicated that SiO2‒TMPDT‒Pb‒Imp had a surface area of 7.418 m2/g, total pore volume of 0.012 cc/g, and pore radius of 16.670 Å. The optimum condition of Pb(II) metal ion adsorption was obtained at pH 5 and a contact time of 60 min that followed the Pseudo Orde 2 adsorption kinetic model with an adsorption capacity of 1.2418 mg/g.