Development of a waste-derived lignin-porphyrin bio-polymer with enhanced photoluminescence at high water fraction with wide pH range and heavy metal sensitivity investigations

ABSTRACTKeratin protein fiber (AKF™) is a renewable source of biosorbent that can be used for filtration of heavy metal and nanosize contaminants. The major composition of keratin fiber is the structured protein micofibril, consisting of numerous nanosized pores. The combination of nanostructure and metal binding capacity protein sites make it an ideal material for removal of heavy metals from solutions. The mechanism of heavy metal uptake onto keratin protein involves a combination of several steps such as adsorption, precipitation, and ion exchange. Keratin protein has good tensile strength and is stable over a wide pH range.

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Use of bentonite to control the release of copper from contaminated soils

Soil Research ◽

10.1071/sr07079 ◽

2007 ◽

Vol 45 (8) ◽

pp. 618 ◽

Cited By ~ 45

Author(s):

Wanting Ling ◽

Qing Shen ◽

Yanzheng Gao ◽

Xiaohong Gu ◽

Zhipeng Yang

Keyword(s):

Heavy Metals ◽

Sorption Capacity ◽

Contaminated Soils ◽

Montmorillonite Clay ◽

Maximum Sorption Capacity ◽

Maximum Sorption ◽

Wide Ph Range ◽

Ph Dependent ◽

Ph Range ◽

Soil Ageing

A decrease in release and availability of heavy metals in soil has been of worldwide interest in recent years. Bentonite is a type of expandable montmorillonite clay, and has strong sorption for heavy metals. In this work, the control of amended bentonite on the release of copper (Cu2+) from spiked soils was investigated using a batch equilibrium technique. Sorption of Cu by bentonite was pH-dependent, and could be well described using the Langmiur model. Maximum sorption capacity of the bentonite used in this study was 5.4 mg/g, which was much greater than soils reported in the literature. The extent of Cu2+ release from spiked soils was correlated with slurry concentrations, pH, and soil ageing process. In all cases, the amendment of bentonite was observed to effectively decrease the release of Cu2+ from soils. The apparent aqueous concentrations of Cu2+ released from soils devoid of bentonite treatment were 113–1160% higher than those from the soils amended with bentonite. Moreover, the magnitude of Cu2+ release decreased with increasing amount of bentonite added to soils. The bentonite added was more effective in retaining Cu2+ in sorbents for aged contaminated soils. Such enhanced retention resulting from the presence of bentonite was observed within a wide pH range from 2.5 to 7.0. Bentonite, as one of the most abundant minerals in soils, is regarded to improve the soil overall quality. The results obtained from this work provide useful information on utilisation of bentonite to control the release of heavy metals from contaminated soils.

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Study on Heavy Metal Contamination in High Water Table Coal Mining Subsidence Ponds That Use Different Resource Reutilization Methods

Water ◽

10.3390/w12123348 ◽

2020 ◽

Vol 12 (12) ◽

pp. 3348

Author(s):

Min Tan ◽

Kun Wang ◽

Zhou Xu ◽

Hanghe Li ◽

Junfeng Qu

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Coal Mining ◽

Control Region ◽

Metal Contamination ◽

Heavy Metal Contamination ◽

High Water ◽

Aquaculture Pond ◽

Coal Mining Subsidence ◽

Resource Reutilization

Heavy metals accumulate in high water table coal mining subsidence ponds, resulting in heavy metal enrichment and destruction of the ecological environment. In this study, subsidence ponds with different resource reutilization methods were used as study subjects, and non-remediated subsidence ponds were collectively used as the control region to analyze the heavy metal distributions in water bodies, sediment, and vegetation. The results revealed the arsenic content in the water bodies slightly exceeded Class III of China’s Environmental Quality Standards for Surface Water. The lead content in water inlet vegetation of the control region and the Anguo wetland severely exceeded limits. Pearson’s correlation, PCA, and HCA analysis results indicated that the heavy metals at the study site could be divided into two categories: Category 1 is the most prevalent in aquaculture pond B and mainly originate from aquaculture. Category 2 predominates in control region D and mainly originates from atmospheric deposition, coal mining, and leaching. In general, the degree of heavy metal contamination in the Anguo wetland, aquaculture pond, and fishery–solar hybrid project regions is lower than that in the control region. Therefore, these models should be considered during resource reutilization of subsidence ponds based on the actual conditions.

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Fabrication of Eco-Friendly Superabsorbent Composites Based on Waste Semicoke

Polymers ◽

10.3390/polym12102347 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2347

Author(s):

Yongsheng Wang ◽

Yongfeng Zhu ◽

Yan Liu ◽

Aiqin Wang

Keyword(s):

Acrylic Acid ◽

Ph Value ◽

High Water ◽

Sem Analysis ◽

Water Absorbency ◽

Ammonium Persulphate ◽

Wide Ph Range ◽

Maximum Water ◽

Ph Range ◽

Superabsorbent Composites

A series of novel superabsorbent composites of poly(acrylic acid)/semicoke were prepared by polymerization of acrylic acid using ammonium persulphate as initiator, N,N′-methylenebisacrylamide as crosslinker and semicoke which was the by-product of coal carbonizing as the inorganic components. FTIR and SEM analysis indicated that the superabsorbent composites had been successfully polymerized and the semicoke participated in construction of the 3D polymeric network. Meanwhile, the effects of initiator, crosslinker, semicoke, and neutralization degree, as well as the pH value, were investigated, and the results showed that superabsorbent composites containing 10% of semicoke possessed the maximum water absorbency of 584 g/g in distilled water and 75 g/g in 0.9% NaCl solution. The superabsorbent composites kept the high water absorbency within a wide pH range of 4–11, and still exhibited better re-swelling capability even after seven times. The superabsorbent composite with its excellent performance is a potential water-retaining agent used in agriculture.

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Adsorption of Cr(VI) and Cu(II) from aqueous solutions by biochar derived from Chaenomeles sinensis seed

Water Science & Technology ◽

10.2166/wst.2020.036 ◽

2019 ◽

Vol 80 (12) ◽

pp. 2260-2272 ◽

Cited By ~ 4

Author(s):

Xiaoling Hu ◽

Jianyang Song ◽

Hongyu Wang ◽

Wei Zhang ◽

Bin Wang ◽

...

Keyword(s):

Heavy Metal ◽

High Efficiency ◽

Low Cost ◽

Maximum Adsorption Capacity ◽

Heavy Metal Remediation ◽

Chaenomeles Sinensis ◽

Wide Ph Range ◽

Different Temperatures ◽

Isotherms And Thermodynamics ◽

Ph Range

Abstract In order to utilize the discarded Chaenomeles sinensis seed (CSS) and develop low-cost biochar for heavy metal pollution control, this study pyrolyzed CSS to prepare biochar at three different temperatures (300, 450 and 600 °C). The physicochemical properties of CSS biochar such as elemental composition, surface area, surface morphology and surface functional groups were characterized. Its adsorption properties including kinetics, isotherms and thermodynamics were studied. The results showed that the adsorption equilibrium was reached at 5 h, which was relatively fast. CSS biochar prepared at 450 °C (CSS450) had the maximum adsorption capacity for Cr(VI) and Cu(II), which was 93.19 mg/g and 105.12 mg/g, respectively. The thermodynamic parameter ΔG0 < 0 and the isotherm parameter RL between 0 and 1 all revealed the feasibility and spontaneity of the adsorption process. The removal of Cr(VI) exhibited high efficiency in a wide pH range (1–10), while the removal of Cu(II) was pH-dependent and optimal at pH = 6. The coexisting ions in the solution showed slight inhibition of the adsorption of Cr(VI) and Cu(II). Additionally, Cu(II) exhibited better affinity for CSS450 than Cr(VI) in dynamic adsorption. This is the first study to prepare biochar from CSS and confirms its potential application for heavy metal remediation.

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Phytochemical Properties and Heavy Metal Contents of Commonly Consumed Alcoholic Beverages Flavoured with Herbal Extract in Nigeria

10.20944/preprints201805.0311.v1 ◽

2018 ◽

Author(s):

Oladapo T. Okareh ◽

Tosin M. Oyelakin ◽

Oluwaseun Ariyo

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Atomic Absorption Spectrophotometry ◽

Herbal Extract ◽

Alcoholic Beverages ◽

Public Health Importance ◽

Safety Awareness ◽

Metal Contents ◽

Ph Range ◽

Ibadan Nigeria

There is proliferation of alcoholic beverages flavoured with herbal-extracts perceived to have medicinal values. Information on the phytochemical and heavy metal contents of these products is scarce. This study assessed the phytochemical properties and heavy metal contents of herbal-extract flavoured alcoholic beverages in major motor parks in Ibadan, Nigeria. The phytochemical properties of the beverages were determined in triplicate using standard methods while the heavy metal contents were assessed using atomic absorption spectrophotometry. Data were analyzed using descriptive statistics and means were compared using ANOVA at p<0.05. The pH range of the beverages was 3.28-6.57 and the alcohol content was 34.0-51.5%. Detected major phytochemicals and concentration ranges were phytic acid (0.72-2.37 mg/g), alkaloids (0.42-4.11 mg/g), flavonoids (0.22-3.64 mg rutin equivalents/g), total phenols (1.13-3.66 mg gallic acid equivalents/g), anthraquinones ((0.74-1.93 mg/g) and triterpenoids (0.74-1.93 mg/g). The phytochemical contents were within the acceptable limits while the heavy metals were: Pb (2.13-4.70 mg/L), Cd (0.06-0.07 mg/L), Co (0.12-0.23 mg/L), Zn (0.14-0.40 mg/L) and Fe (0.72-4.22 mg/L); all except Pb and Cd were within permissible limits. The herbal-extract flavoured alcoholic beverages contain beneficial phytochemicals and traces of heavy metals. Safety awareness of these products for improved consumers’ health would be of public health importance.

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Efficient removal of heavy metals from melting effluent using multifunctional hydrogel adsorbents

Water Science & Technology ◽

10.2166/wst.2018.380 ◽

2018 ◽

Vol 78 (4) ◽

pp. 982-990 ◽

Cited By ~ 2

Author(s):

Jianhong Ma ◽

Yuanmeng Zhang ◽

Yanhong Tang ◽

Yuanfeng Wei ◽

Yutang Liu ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Mechanical Strength ◽

Metal Removal ◽

Heavy Metal Removal ◽

High Water ◽

Poly Vinyl Alcohol ◽

Removal Of Heavy Metals ◽

Cross Linkage ◽

Removal Efficiencies

Abstract It is hard to balance high water permeability and good mechanical strength of hydrogel adsorbents. In this study, an enhanced double network hydrogel adsorbent of poly (vinyl alcohol)/poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PVA/PAMPS) was prepared via simple free-radical polymerization. Hydrophilic PAMPS guaranteed high swellability of the adsorbent, which made the sufficient diffusion of metal ions towards adsorbent inside. Meanwhile, the cross-linkage between PVA and PAMPS chains ensured good mechanical strength of the adsorbent. Significantly, the introduction of multifunctional groups (-NHR, -SO3H and -OH) endowed the adsorbent with both chelation and ion exchange function for enhancing heavy metal adsorption. The maximum adsorption capacities of Pb2+ and Cd2+ reached 340 and 155.1 mg/g, respectively. The adsorbent could efficiently remove heavy metals in melting effluent, especially Pb2+ and Cd2+. The removal efficiencies reached 88.1% for Pb2+, 91.4% for Cd2+, 70.4% for Zn2+, 77.4% for Cu2+, 42.5% for Mn2+, 45.1% for Ni2+ and 95.4% for Fe3+ using 2 g/L adsorbent in 2 h. Moreover, the adsorbent showed a good reusability, and the removal efficiencies maintained 94% for Pb2+ and 93% for Cd2+ in the fifth cycle (m/V = 1 g dry gel/L). This work developed a highly practical hydrogel adsorbent for heavy metal removal from wastewater.

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Remarkable Acid Stability of Polypyrrole-MoS4 : A Highly Selective and Efficient Scavenger of Heavy Metals Over a Wide pH Range

Advanced Functional Materials ◽

10.1002/adfm.201800502 ◽

2018 ◽

Vol 28 (20) ◽

pp. 1800502 ◽

Cited By ~ 31

Author(s):

Linxia Xie ◽

Zihuan Yu ◽

Saiful M. Islam ◽

Keren Shi ◽

Yahan Cheng ◽

...

Keyword(s):

Heavy Metals ◽

Acid Stability ◽

Wide Ph Range ◽

Ph Range

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Heavy Metal Status of Major Vegetable Farmsoils in Ilorin Metropolis, Kwara State, Nigeria

Journal of Applied Sciences and Environmental Management ◽

10.4314/jasem.v24i3.11 ◽

2020 ◽

Vol 24 (3) ◽

pp. 467-472

Author(s):

P.O. Ben-Uwabor ◽

G.K. Olawepo ◽

C.O. Ogunkunle ◽

P.O. Fatoba

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Pollution Index ◽

Atomic Absorption Spectrophotometry ◽

Elevated Concentration ◽

Ph Range ◽

Vegetable Farm ◽

Farm Soils ◽

Different Levels ◽

Range Test

Soils in developing areas have been confirmed by researchers to be contaminated with heavy metals which are a major category of pollutants. Previous projects had been carried out to ascertain different levels of heavy metals in soils but this paper targets heavy metals and degree of pollution of major vegetable farm soils in Ilorin metropolis, Kwara State, Northern Nigeria. Therefore, this work aimed at determining the; concentrations of total heavy metals (HMs) and the pollution index of the major vegetable farm soils. Total cadmium (Cd), copper (Cu) and lead (Pb) in soils were determined by acid digestion and Atomic Absorption Spectrophotometry method. Data generated were subjected to Analysis of Variance (ANOVA) and mean separated using Duncan Multiple Range Test (DMRT) at 5% significance. HMs in soils were: Cd (0.00-4.67), Cu (1.71-30.08) and Pb (1.29-82.00) mg/kg with pH range of 6.62-9.33 and pollution index range of Cd (0.00-2.90), Cu (0.86- 11.72) and Pb (0.70-14.30). Some soils showed elevated concentration of Cd and Pb higher than the recommended permissible – limit (Cd=1.00 mg/kg, Pb=70.00mg/kg) with pollution index of HMs ranged from low pollution to very strong pollution (0.00±0.00- 14.30±1.77). The study therefore, suggested that there could be a risk of Cd and Pb associated diseases on the consumption of vegetables planted on some of these soils. Keywords: Heavy metal content, pollution index, vegetable farmsoils, Ilorin metropolis.

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