Article
Environmental Sciences
Zongqiang Zhu, Huiling Jiang, Yinian Zhu, Lihao Zhang, Shen Tang, Xiaobin Zhou, Yinming Fan
Summary: In this study, strontium-doped hydroxyapatite (Sr-HAP) was synthesized and found to have higher adsorption capacity for lead ions. Increasing the dosage and temperature enhanced the adsorption capacity. Sr-HAP had increased specific surface area and more uniform pore size distribution, making it an ideal adsorbent for removing lead ions from wastewater.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Environmental Sciences
Yijing Xu, Hongmei Tang, Pingxiao Wu, Meiqing Chen, Zhongbo Shang, Jiayan Wu, Nengwu Zhu
Summary: The serious pollution of water by lead (Pb(II)) and cadmium (Cd(II)) poses a significant threat to ecological safety and requires urgent solutions. In order to improve the adsorption performance of pure hydroxyapatite, which has a relatively low adsorption rate for heavy metals, a series of manganese-doped hydroxyapatites (MnHAPs) were prepared. The presence of manganese influenced the formation and growth of hydroxyapatite crystals, resulting in lattice distortion and a large number of lattice defects. MnHAP-10, with a Mn/(Ca +Mn) molar ratio of 10%, exhibited the most effective removal of Pb(II) and Cd(II), with adsorption capacities of 1806.09 mg g-1 for Pb(II) at pH = 5 and 176.88 mg g-1 for Cd(II) at pH = 5.5. The adsorption behavior and mechanism were further investigated, indicating that Pb(II) was immobilized mainly through dissolution precipitation and ion exchange, while Cd(II) was adsorbed by ion exchange and electrostatic interaction. In conclusion, MnHAP-10 has great potential as an effective adsorbent for the removal of Pb(II) and Cd(II) pollution.
Article
Materials Science, Ceramics
Yuting Zhou, Weidong Li, Xia Jiang, Yan Sun, Huayun Yang, Qi Liu, Yong Cao, Yun Zhang, Haixiang Cheng
Summary: In this study, a novel strontium-doped hydroxyapatite nanorods were synthesized for enhanced chromium (VI) adsorption, achieving significantly higher adsorption capacity than undoped hydroxyapatite nanorods. The Langmuir isotherm model was used to reveal that monolayer chemical adsorption played a crucial role in efficient chromium (VI) ion removal by strontium-doped hydroxyapatite nanorods, with surface area and surface functional groups contributing to the differences in adsorption capacities between HAp and Sr-HAp.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Analytical
Abdelkarim Brahimi, Abdelhamid Mellah, Salah Hanini
Summary: The study used Bottom Ash of Expired Drug Incineration (BAEDI) for the removal of Sr(II), finding that the pseudo-second order and ninth order models fit the data, and the thermodynamic study indicated a spontaneous, endothermic process with increased affinity for Sr2+. The adsorption of Sr2+ was found to be of a physical nature, and the Langmuir model calculated a maximum adsorption capacity of 38 mgg(-1).
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
(2021)
Article
Engineering, Environmental
Wipark Anutrasakda, Apakorn Phasuk, Chutima Tangku
Summary: Hydroxyapatite and carbonate-substituted hydroxyapatite materials were prepared using a hydrothermal method, with higher CO32- concentrations resulting in smaller particle size, lower crystallinity, and higher surface area. CHAP15 exhibited superior Pb(II) adsorption performance, with the adsorption mechanism involving the formation of poorly-soluble compounds through the reaction of Pb(II) ions with phosphate and carbonate ions.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Materials Science, Paper & Wood
Ji Won Heo, Liangliang An, Jiansong Chen, Min Soo Kim, Sang-Deok Lee, Yong Sik Kim
Summary: Aminated lignins exhibited optimal adsorption capacities for Cd(II) and Pb(II) metal ions under neutral conditions, with the primary amine group showing the highest adsorption capacities. The adsorption behaviors followed Langmuir isotherm and pseudo-second-order kinetics, and the thermodynamic studies revealed that the adsorption processes were spontaneous and endothermic. These results demonstrate that aminated lignins are promising adsorbents for the removal of Cd(II) and Pb(II) metal ions.
Article
Chemistry, Physical
Sivakumar Vigneshwaran, Palliyalil Sirajudheen, Perumal Karthikeyan, Sankaran Meenakshi
Summary: In this study, a sulfur tethered adsorbent of Tapioca peel (S@TP) biochar was successfully fabricated and utilized for the removal of organic dyes such as Malachite Green (MG) and Rhodamine B (RhB) from water, showing adsorption efficiency of 30.18 and 33.10 mg/g, respectively.
SURFACES AND INTERFACES
(2021)
Article
Engineering, Environmental
Ying Wang, Haoyu Chen, Chao Chen, Zikun Zhang, Yin Xu, Guangjiao Chen, Yanlong Zhang
Summary: The composition and properties of aHAP, a byproduct of the anammox-HAP process, were analyzed. The aHAP showed good adsorption capacity for Cd(II) removal and pH buffering capacity. This research contributes to achieving high-efficiency nitrogen and phosphorus removal and meeting the requirements of green chemistry.
JOURNAL OF WATER PROCESS ENGINEERING
(2022)
Article
Chemistry, Physical
Yanru Zhang, Mingzhu Xia, Fengyun Wang, Jianzhe Ma
Summary: ATMP functionalized HAP exhibited high adsorption performance towards Pb2+ and Cd2+, with ion exchange and surface complexation as the main adsorption mechanisms. XRD results showed different adsorption characteristics for Pb2+ and Cd2+, indicating the involvement of dissolution-precipitation in Pb2+ adsorption.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2021)
Article
Water Resources
Theresa C. Umeh, John K. Nduka, Kovo G. Akpomie
Summary: The study measured the lead and cadmium contents in soil from a farming site in Enugu, Nigeria using atomic absorption spectrophotometer, and found that the soil can be utilized as a low cost-effective adsorbent to minimize the environmental risk impact of these metal ions. The results showed a satisfactory correlation for Langmuir model with better linear regression coefficients for both Pb2+ and Cd2+, indicating the soil's potential as an effective adsorbent.
APPLIED WATER SCIENCE
(2021)
Article
Polymer Science
Rachid El Kaim Billah, Ikrame Ayouch, Youness Abdellaoui, Zineb Kassab, Moonis Ali Khan, Mahfoud Agunaou, Abdessadik Soufiane, Marta Otero, Byong-Hun Jeon
Summary: A novel polymer bio-composite (CS/n-Hap) consisting of nano-hydroxyapatite (n-Hap) and chitosan (CS) was synthesized for the efficient removal of toxic cadmium ions from water. The CS/n-Hap bio-composite exhibited superior adsorption capacity compared to pristine CS, with a maximum uptake of 126.65 mg/g under optimized conditions. The adsorption mechanism involved the formation of chemical bonds between Cd(II) and CS/n-Hap, as confirmed by the kinetic and thermodynamic studies.
Article
Engineering, Chemical
Marija Koprivica, Marija Simic, Jelena Petrovic, Marija Ercegovic, Jelena Dimitrijevic
Summary: Hydrothermal carbonization (HTC) was used to convert Paulownia leaves (PL) into a carbonaceous sorbent for Pb(II) removal from aqueous solutions. Alkali activation using NaOH was performed to enhance the adsorption efficiency of the obtained hydrochar (PH). The results showed that the alkali treatment improved the adsorption performance of the hydrochar and the Langmuir isotherm model best described the experimental data.
Article
Environmental Sciences
Deva Nand Sharma, Anil Yadav
Summary: This paper presents a novel adsorbent, Chhotidudhi, for the removal of nickel ions from aqueous solutions. The adsorbent was characterized using FTIR, XRD, SEM, and TGA. The adsorbent showed strong bond with metals and had an amorphous structure with a porous morphology. At optimized conditions, the adsorption capacity for the adsorbent was 52.4 mg/g and 109.05 mg/g, with removal efficiencies of 81.6% and 93.8% for ETR and ETA, respectively. The experimental results fit well with Langmuir and pseudo-second-order reactions.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Multidisciplinary Sciences
Mehmet Emin Kucuk, Iryna Makarava, Teemu Kinnarinen, Antti Hakkinen
Summary: In this study, NaP and LTA zeolites were successfully synthesized from woody biomass ash using alkali fusion-assisted hydrothermal method. The synthesized zeolites were tested for the adsorption of Cu(II), Cd(II), Pb(II), and Zn(II) ions. The results showed that the maximum adsorbed amount of metals followed the order Pb(II) > Cu(II) > Cd(II) > Zn(II) for both NaP and LTA zeolite. The kinetic data fit well with the pseudo-second order model, indicating chemisorption as the rate-limiting step. The isotherm data were well described by the Sips and Redlich-Peterson models, indicating a non-ideal heterogeneous adsorption process.
Article
Environmental Sciences
Shahjalal Khandaker, Md Tofazzal Hossain, Palash Kumar Saha, Ummey Rayhan, Aminul Islam, Tasrina Rabia Choudhury, Md. Rabiul Awual
Summary: In this study, inexpensive bamboo was utilized to create activated charcoal for efficient encapsulation of toxic copper ions from wastewater. The functionalized bamboo charcoal-Layered double hydroxides composite bio-adsorbent showed high sensitivity and selectivity in removing Cu(II) ions. Various parameters were optimized, and analyses were conducted to understand the structure and adsorption mechanism of the composite bio-adsorbent.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2021)