JOURNAL OF SOILS AND SEDIMENTS
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2024
·Vol. 24
·期 6
·2309-2317
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IF 2.8
Mi Na,Yang Min,Wang Xiaohan,Sun Qian,He Jianzhou,Deng Shaopo,Fan Tingting
Purpose The application of silicon could effectively alleviate Cd contamination in the soil. However, the interaction between silicon and Cd in soils is not well understood. Our research aims to investigate the mechanism of the impact of silicate on the sorption of Cd on metal oxides in soils. Materials and methods Sodium silicate and Cd(II) co-sorption on γ-Al 2 O 3 and goethite at pH 5.5 and 7.5 was studied using a combination of batch sorption experiments, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Results and discussion Silicate enhanced the sorption of Cd(II) onto γ-Al 2 O 3 at pH 5.5 and 7.5. However, the sorption of Cd(II) on goethite at pH 5.5 and 7.5 was only promoted when the silicate concentration reached 1 mmol L −1 . Cadmium(II) enhanced silicate sorption on γ-Al 2 O 3 at pH 5.5 and on goethite at pH 7.5, while it decreased silicate sorption on γ-Al 2 O 3 at pH 7.5 and had no significant effect on goethite at pH 5.5. At pH 5.5, Cd(II) reacted with silicate to generate Cd 2 SiO 4 , and Cd-Si-Al ternary complexes were formed on γ-Al 2 O 3 . At pH 7.5, silicate promoted the formation of Cd(OH) 2 on γ-Al 2 O 3 , which ultimately transformed into CdCO 3 . When silicate concentration reached 1 mmol L −1 , more silicate complexes were formed through the Fe-O-Si bound on goethite at both pH 5.5 and 7.5 to promote the adsorption of Cd(II) owing to its electronegative functional group on the surface of the complex. Conclusions The type of clay minerals, pH, and the presence of silicate all significantly affected Cd sorption. Furthermore, the sorption mechanism of Cd on γ-Al 2 O 3 and goethite in the presence of silicate has been elucidated. The above findings improve our understanding of the mechanism for immobilizing Cd in soils using silicon-containing materials.
研究领域:
土壤科学
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环境化学
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DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Haoyue Tang,Yu Zhang,You Wu,Wenyu Wu,Shiying Bi,Junjie Wu,Shitong Yang
Turning agricultural wastes into green adsorbents is a compatible and cost-effective strategy for solid waste disposal and environmental pollution control. Herein, the discarded orange peel (OP) sample was purified via coupled alkali-acid hydrolysis and the obtained adsorbents were applied for eliminating toxic cadmium (Cd(II)) from the liquid phase. Based on the single factor experiments, the optimal Cd(II)-capturing adsorbent (i.e., OP-OH-H-25) was generated under the purification condition of soaking raw OP in 2.0 M NaOH solution at 25 °C followed by an acid hydrolysis treatment with 2.5 M HCl solution at 25 °C. Spectral analyses reflected the efficient elution of hemicellulose/pectin and lignin impurities, the transformation of cellulose type I to cellulose type II, and the exposure of sulfhydryl functional groups. The kinetics removal process of Cd(II) by OP-OH-H-25 reached equilibrium after 0.5 h with a removal efficiency of ∼88%. The maximum Cd(II) sorption capacity of OP-OH-H-25 (i.e., 124.90 mg/g) was higher than a series of previously reported adsorbents. The sorption behavior of Cd(II) onto the prepared OP-OH-H-25 material was mostly interfered with by the coexisting Mg 2+ , Ca 2+ , and heavy metals. The desorption data and spectroscopic analysis jointly pointed to the inner-sphere binding of Cd(II) with OP-OH-H-25 functional groups. Overall, the extracted OP-OH-H-25 sample could act as a promising decontaminant for the remediation of Cd(II)-polluted water environment.
研究领域:
环境科学
·
生物化学
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DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Qi Yao,Yaqi Peng,Min Chen,Yufeng Wang,Jiamin Ding,Binbin Ma,Qionghao Wang,Shengyong Lu
The hydrothermal synthesis of zeolite from fly ash is a time-consuming process with a low conversion rate. Mechanochemical activation is commonly employed as a green and moderate pre-treatment process for surface modification purposes. This study proposes a one-step high efficiency synthesis of zeolite from fly ash using the mechanochemical method. The ball milling modification is conducted simultaneously with the zeolite synthesis process, reducing the overall synthesis time to a significant extent (3 h being determined as the optimal synthesis time). The findings reveal that P1 zeolite can be effectively synthesized under the following conditions: a sodium hydroxide concentration of 2 mol L −1 , a synthesis temperature of 130 °C and a ball milling frequency of 30 Hz. Moreover, the synthesized zeolite exhibits a maximum Cd 2+ adsorption capacity of 130.68 mg/g at pH= 5, following pseudo-second-order kinetics and Langmuir adsorption isotherm . This study not only simplifies the production process and saves energy but also yields zeolite with smaller particle sizes and higher purity. By utilizing the mechanochemical method, the disposal of solid waste can be made environmentally friendly, convenient, and economically beneficial.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 54
·28699-28706
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IF 3.708
Xiao-kun OuYang,Ru-Na Jin,Le-Ping Yang,Yang-Guang Wang,Li-Ye Yang
Two porous bioadsorbents were successfully prepared from the partial enzymatic hydrolysis of bamboo and subsequent chemical modification with succinic anhydride. We investigated the abilities of the partially enzymatically hydrolyzed bamboo (PEB) and the porous succinylated bamboo (PSB) to adsorb Cd(II) from a solution containing sodium chloride and an amino acid. The partial enzymatic hydrolysis created many pores within the raw bamboo, and both the porous structure and the post-succinylation carboxyl group content were important for high adsorption capacity. The presence of sodium chloride and the amino acid markedly decreased the adsorption capacities of the bioadsorbents. The experimental data could be described perfectly with the Langmuir adsorption isotherm model and pseudo second-order kinetics model. Even in solutions containing sodium chloride and arginine, the maximum Cd(II) adsorption capacities at 303 K were 38.18 and 120.34 mg g−1 for PEB and PSB, respectively.
研究领域:
环境科学
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材料科学
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生物技术
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DOI
高影响因子
Bioresource Technology Reports
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2022
·
IF 0
Sen Lin,Yihong Guo,Lei Zhou,Hongjun Yang
Quantitative effects of surface oxidation on Cd 2+ adsorption performance of biochar derived from long-root Eichhornia Crassipes plants were systematically investigated. It was revealed that oxidation degree was positively related with the intensity of surface functional groups and harmless for the structural stability, while biochar yield would decline sharply resulting from for over-oxidization. Correspondingly, the Cd 2+ adsorption capacity exhibited an uptrend with the increasing oxidation on account of the abundant adsorption sites. Moreover, Cd 2+ adsorption on the biochar with different oxidation degrees were also investigated comprehensively, indicating adsorption performances in a similar trend highly sensitive to solution pH and ionic strength . In addition, the adsorption isotherms were found to manifest the saturated adsorption capacity for Cd 2+ increased from 0.333 mol/g to 0.487 mmol/g at 30 °C by strengthening oxidation. All synthesized biochar could keep consistent adsorption performance in multiple adsorption-desorption cycles.
研究领域:
环境科学
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材料科学
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生态学
✓ 已验证
DOI
SCIENCE OF THE TOTAL ENVIRONMENT
·
2020
·
IF 6.551
Qianjun Liu,Jiepeng Tang,Xiang Li,Qintie Lin,Rongbo Xiao,Min Zhang,Guangcai Yin,Yangmei Zhou
Lignin is a precursor of humus in soil and sediment. Lignin can be separated from vascular plants in the form of lignosulfonate via pulping processes. On the other hand, composites of iron oxide and organic matter can adsorb heavy metals, and thus influence the migration of these heavy metals in the environment. In this paper, a hematite/lignosulfonate composite (HLS) was prepared via coprecipitation to compare the adsorption performance of hematite (α-Fe 2 O 3 ) toward Cd(II) before and after the incorporation of lignosulfonate (LS). The HLS is found to exhibit a weakly crystalline structure and possess a large number of nanoscale particles . Specific surface area of HLS (291.97 m 2 /g) is about 11 times that of α-Fe 2 O 3 , and the pore volume of HLS (0.22 cm 3 /g) is twice that of α-Fe 2 O 3 . The adsorption of Cd(II) is well illustrated by the pseudo-second-order adsorption kinetics and the initial adsorption rate ( h ) of HLS is 13.83 times that of α-Fe 2 O 3 . The maximum adsorption capacities are significantly improved from 4.89–6.35 mg/g (α-Fe 2 O 3 ) to 39.03–53.65 mg/g (HLS). A greater affinity and more favorable association between Cd(II) and HLS is observed via fitting models. The incorporation of LS provides HLS with significantly better adsorption properties toward Cd(II) than α-Fe 2 O 3 , as is further confirmed by FT-IR and XPS characterization. Fe-O-O-H and Fe-O-H structures as well as more hydroxyl groups are observed, which promote the adsorption performance since the process are mainly influenced by complexation via coordination bonds.
研究领域:
环境科学
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土壤学
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产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
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2021
·Vol. 45
·期 28
·12669-12677
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IF 3.591
Yu Jiang,Chen Yang,Qian Yao,Yurong Deng,Jingjing Yang,Yanjun Liu,Zhuozhi Ouyang,Weilin Huang,Zhi Dang
To clarify the function of the nitrogen-containing structures on the adsorption of heavy metals, nitrogen-enriched biochars (NBCs) mainly composed of pyrrolic, pyridinic, and graphitic nitrogen were prepared to investigate the interaction mechanism with Cd(II). The results of batch experiments revealed that the saturated Cd(II) adsorption capacities of Pr-NBC, Pd-NBC, and Gp-NBC were 12.68, 24.04, and 35.95 mg g−1 respectively. The strongest adsorption ability was found for the Gp-NBC and was ascribed to the enhancement of graphitic nitrogen. The results from SEM-EDS and XRD, and the zeta potentials for the materials revealed that carbonate precipitation, cation exchange, and electrostatic interactions contributed to the adsorption of Cd(II). XPS and FTIR demonstrated that nitrogen in the carbon framework might have promoted the adsorption by forming cation–π interactions between graphitic nitrogen and Cd(II). The electrostatic potential distribution of the nitrogen with different configurations fully confirmed this. The theoretical calculations also proved that graphitic nitrogen had the lowest interaction energy to Cd(II), which further verified the strong contribution of graphitic nitrogen to the adsorption of heavy metal. Nitrogen-enriched biochar effectively adsorbs, changes the migration process of heavy metals in the natural environment, and thus alleviates the current situation of heavy metal pollution.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2019
·
IF 6.669
Jianhong Ma,Tong Li,Yutang Liu,Tao Cai,Yuanfeng Wei,Wanyue Dong,Hui Chen
In this study, lignin extracted from rice husk was used to synthesis double network hydrogel adsorbent, named RH-CTS/PAM gel. RH-CTS/PAM gel exhibited macroporous structure and high buried water content, which gave rise to the exceptional adsorption performance. As results, in individual systems, the equilibrium time of Pb(II), Cu(II) and Cd(II) with initial concentration of 200 mg/L could be reached within 10 min, with the theoretical maximum adsorption capacity of 374.32, 196.68 and 268.98 mg/g, respectively. The adsorption rate and capacity of Pb(II), Cu(II) and Cd(II) in multicomponent systems were lower than that of individual systems. However, in a few cases of ternary system, higher adsorption rate and capacity was observed compare to binary systems. Adsorption mechanism indicated that both oxygen-containing and nitrogen-containing functional groups played a dominant role during the adsorption process, and mainly through chemical interaction along with a small amount of physical interaction.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL RESEARCH
·
2020
·
IF 5.715
Xiangping Li,Chuanbin Wang,Jingnan Tian,Juping Liu,Guanyi Chen
Using biochar to remove heavy metals from water is environmentally beneficial. In this study, three kinds of chemical reagents, including ZnCl 2 , H 3 PO 4 and KMnO 4 , were introduced to modify the biochar derived from Enteromorpha prolifera . The performance of these modified biochar in removing Cadmium ions (Cd(II)) from water was investigated. The physicochemical properties of activated biochars were characterized by N 2 -sorption, thermal gravity and differential thermal gravity (TG/DTG), scanning electron microscopy (SEM), elemental analysis and Fourier transform infrared spectroscopy (FTIR). The results showed that the removal rate of Cd(II) from water by EP biochar modified with H 3 PO 4 was significantly increased, and the maximum adsorption capacity of Cd(II) reached to 423 mg/g for PBC. Moreover, the adsorption of Cd(II) from water by phosphoric acid modified biochar was very fast, and the saturation adsorption of Cd(II) was reached within 1 h. Compared with pseudo first-order model, pseudo secondary-order model was much more suitable for analyzing the adsorption kinetics data of Cd(II) onto KBC or ZBC. The adsorption of Cd(II) onto PBC was analyzed by the intra-particle diffusion kinetic model, where the value of R 2 was high as 0.98. The Langmuir model was fit for phosphoric acid modified biochar.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
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2024
·Vol. 46
·期 8
·1-12
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IF 3.2
Xu Ren-kou,Nkoh Jackson Nkoh
Soil organic matter plays an important role in cadmium adsorption and immobilization. Since different organic matter components affect cadmium adsorption processes differently, selecting the right organic substrate and knowing how to apply it could improve cadmium remediation. This study compares the effects of two contrasting organic molecules; chitosan and citric acid, on cadmium adsorption and speciation in acidic Ultisol. The adsorption of chitosan to Ultisol significantly increased the soil positive charge while adsorption of citric acid increased the soil negative charge. At pH 5.0, the maximum amount of cadmium adsorbed in excess chitosan was 341% greater than that in excess citric acid. About 73–89% and 60–62% of adsorbed cadmium were bound to Fe/Mn oxides and organic matter/sulfide at pH 4.0 while this fraction was 77–100% and 57–58% for citric acid and chitosan at pH 5.0, respectively. This decrease in the complexing ability of chitosan was related to the destabilizing effect of high pH on chitosan’s structure. Also, the sequence through which chitosan, citric acid, and cadmium were added into the adsorption system influenced the adsorption profile and this was different along a pH gradient. Specifically, adding chitosan and cadmium together increased adsorption compared to when chitosan was pre-adsorbed within pH 3.0–6.5. However, for citric acid, the addition sequence had no significant effect on cadmium adsorption between pH 3.0–4.0 compared to pH 6.5 and 7.5, with excess citric acid generally inhibiting adsorption. Given that the action of citric acid is short-lived in soil, chitosan could be a good soil amendment material for immobilizing cadmium.
研究领域:
环境科学
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土壤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Saeed Rehman,Jiayan Wu,Muddasir Hanif,Tianming Wang,Minye Huang,Tang Hongmei,Shang Zhongbo,Pingxiao Wu,Fazal Raziq
This research is focused on studying the effects of different dissolved organic matter (DOM) and electrolyte concentration on the Cd(II) adsorption on halloysite (HNT) surfaces. The DOM significantly decreased the Cd(II) adsorption by more than 25 %. Soil derived dissolved organic matter (SDT) showed the greatest negative impact, followed by humic acid (HA) and Fulvic acid (FA). The effects of background electrolytes NaCl and NH 4 Cl showed that both salts can undergo complexation with metals. Furthermore, the DOM (SDT/FA/HA) can cover the major HNT surface and the Cd(II) adsorption may occur due to outer-sphere complexation and ion exchange. Additionally, the influence of 100 mML −1 of NaCl on the aggregation tendencies of HNT has demonstrated that the presence of DOM amplifies the aggregation behavior of these nanotubes . The interaction energy barrier between HNT particles is dependent on physicochemical characteristics of DOM that inhibits Cd(II) sorption . These findings suggested that the HNT reduction, electrostatic repulsion and site-competition are the prominent mechanisms to decrease the Cd(II) immobilization on the HNT. The extent of Cd(II) adsorption/desorption on HNT surface followed the order of FA > HA > SDT/ HA > SDT > FA.
研究领域:
环境科学
·
土壤学
✓ 已验证
产品关联
DOI
高影响因子
Toxics
·
2024
·Vol. 12
·期 10
·717
·
IF 3.9
Yanwei Hou,Shanna Lin,Jiajun Fan,Youchi Zhang,Guohua Jing,Chao Cai
In the environmental field, the advancement of new high-efficiency heavy metal adsorption materials remains a continuous research focus. A novel composite, covalent organic framework-modified biochar (RH-COF), was fabricated via an in-situ polymerization approach in this study. The COF-modified biochar was characterized by elemental analysis, BET analysis, SEM, FT-IR, and XPS. The nitrogen and oxygen content in the modified material increased significantly from 0.96% and 15.50% to 8.88% and 22.37%, respectively, indicating the addition of a substantial number of nitrogen- and oxygen-containing functional groups to the RH-COF surface, thereby enhancing its adsorption capacity for Cd from 4.20 mg g−1to 58.62 mg g−1, representing an approximately fourteen-fold increase. Both the pseudo-second-order model and the Langmuir model were suitable for describing the kinetics and isotherms of Cd2+adsorption onto RH-COF. The adsorption performance of Cd2+by RH-COF showed minimal sensitivity to pH values between 4.0 and 8.0, but could be slightly influenced by ionic strength. Mechanistic analysis showed that the Cd2+adsorption on RH-COF was dominated by surface complexation and chelation, alongside electrostatic adsorption, surface precipitation, and Cπ–cation interactions. Overall, these findings suggest that the synthesis of COF-biochar composite may serve as a promising remediation strategy while providing scientific support for applying COF in environmental materials.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）