scholarly journals Investigation of locust bean husk char adsorbability in heavy metal removal

2017 ◽  
Vol 63 (No. 1) ◽  
pp. 29-35
Author(s):  
Ajayi-Banji Ademola ◽  
Ogunlela Ayo ◽  
Ogunwande Gbolabo
Keyword(s):  
Heavy Metal ◽  
Removal Efficiency ◽  
Retention Time ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Freundlich Isotherm ◽  
Polluted Water ◽  
Safe Level ◽  
Column Adsorption ◽  
Locust Bean

he column adsorption study examines irrigation water treatment prior to its application in order to ensure water-crop-consumer heavy metal transfer reduction to the safe level using locust bean husk char (LBHC) as biosorbent. Char structural pattern was investigated with SEM-EDX machine. Contaminated surface water was introduced simultaneously into the bioreactors containing 100 and 200 g of LBHC and collected after 30, 60, 90 120 and 150 min of detention time. Removal efficiency, isotherm and kinetic sorption model were the evaluation tools for the study. Percent of Cr, Cd and As removal at 150 min retention time were 83.33, 100 and 100%, respectively for 100 g biosorbents. A similar trend was observed for Cr and As removal at the same retention time for 200 g of LBHC. Metals sorption conforms to the Freundlich isotherm with correlation coefficient values greater than 0.92. Experimental kinetics had a good fit for pseudo second order (R<sup>2</sup> &gt; 0.94 for most cases). Removal efficiency is a function of contact time, biosorbent dosage and metal concerned. Locust bean husk char has good and effective treatability for some heavy metals in mildly polluted water.

Electrokinetic Remediation of Heavy Metal Contaminated Soil Using Permeable Reactive Composite Electrodes

2012 ◽  
Vol 518-523 ◽  
pp. 361-368 ◽  
Author(s):  
Rong Bing Fu ◽  
Xin Xing Liu ◽  
Fang Liu ◽  
Jin Ma ◽  
Yu Mei Ma ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Removal Efficiency ◽  
Heavy Metal Ions ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Ph Control ◽  
Electrokinetic Remediation ◽  
Composite Electrodes ◽  
Remediation Process

A new permeable reactive composite electrode (PRCE) attached with a permeable reactive layer (PRL) of Fe0 and zeolite has been developed for soil pH control and the improved removal efficiency of heavy metal ions (Cd, Ni, Pb, Cu) from soil in electrokinetic remediation process. The effects of different composite electrodes on pH control and heavy metal removal efficiency were studied, and changes in the forms of heavy metals moved onto the electrodes were analyzed. The results showed that with acidic/alkaline zeolite added and renewed in time, the composite electrodes could effectively neutralize and capture H+ and OH- produced from electrolysis of the anolyte and catholyte, avoiding or delaying the formation of acidic/alkaline front in tested soil, preventing premature precipitation of heavy metal ions and over-acidification of soil, and thus significantly improved the heavy metal removal efficiency. Fe0 in composite electrodes could deoxidize and stabilize the heavy metal ions. After that capture and immobilization of the pollutants were achieved. The results also showed that, using "Fe0 + zeolite" PRCE in the cathode with timely renewal, after 15-day remediation with a DC voltage of 1.5 V/cm, the total removal rates of Cd, Pb, Cu and Ni were 49.4%, 47.1%, 36.7% and 39.2%, respectively.

scholarly journals Growth and metal removal efficiency of the green algae Schroederia setigera and Selenastrum bibraianum exposed to nickel, zinc and cadmium

2020 ◽  
Vol 58 (5A) ◽  
pp. 22
Author(s):  
Dao Thanh Son ◽  
Van Tai Nguyen ◽  
Thuy Nhu Quynh Vo ◽  
Vinh Quang Tran ◽  
Thi My Chi Vo ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Green Algae ◽  
Removal Efficiency ◽  
Heavy Metal Contamination ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Pilot Scale ◽  
Nickel Zinc ◽  
Ecological Protection

Heavy metal contamination is among the globally environmental and ecological concerns. In this study we assessed the development of the two green algae Schroederia setigera and Selenastrum bibraianum under exposures to 5 – 200 µg/L of Ni, Zn, and Cd in the laboratory conditions. Heavy metal removal efficiency of S. setigera was also tested in 537 µg Ni/L, 734 µg Zn/L, and 858 µg Cd/L. We found that the exposures with these heavy metals caused inhibitory on the growth of S. bibraianum. The S. bibraianum cell size in the 200 µg Zn/L treatment was around two times smaller than the control. However, Zn and Cd at the concentration of 200 µg/L did not inhibit the growth of S. setigera over 18 days of exposure. The S. setigera also grew well during 8 days exposed to Ni at the same concentration. Besides, the alga S. setigera could remove 66% of Zn, 18% of Cd and 12% of Ni out of the test medium after 16 days of incubation. The Vietnam Technical Regulation related to metals should be considered for ecological protection. We recommend to test the metal removal by the alga S. setigera at pilot scale prior to apply it in situ

Potential of Agricultural Waste Material (Ananas cosmos) as Biosorbent for Heavy Metal Removal in Polluted Water

2020 ◽  
Vol 1010 ◽  
pp. 489-494
Author(s):  
Abdul Hafidz Yusoff ◽  
Rosmawani Mohammad ◽  
Mardawani Mohamad ◽  
Ahmad Ziad Sulaiman ◽  
Nurul Akmar Che Zaudin ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Adsorption Capacity ◽  
Metal Removal ◽  
Low Cost ◽  
Agricultural Waste ◽  
Heavy Metal Removal ◽  
Polluted Water ◽  
Maximum Adsorption Capacity ◽  
Pineapple Peel

Conventional methods to remove heavy metals from polluted water are expensive and not environmentally friendly. Therefore, this study was carried out to investigate the potential of agricultural waste such as pineapple peel (Ananas Cosmos) as low-cost absorbent to remove heavy metals from synthetic polluted water. The results showed that Cd, Cr and Pb were effectively removed by the biosorbent at 12g of pineapple peels in 100 mL solution. The optimum contact time for maximum adsorption was found to be 90 minutes, while the optimum pH for the heavy metal’s adsorption was 9. It was demonstrated that with the increase of adsorbent dosage, the percent of heavy metals removal was also increased due to the increasing adsorption capacity of the adsorbent. In addition, Langmuir model show maximum adsorption capacity of Cd is 1.91 mg/g. As conclusions, our findings show that pineapple peel has potential to remove heavy metal from polluted water.

Removal of Some Heavy Metals by Electrocoagulation

2012 ◽  
Vol 468-471 ◽  
pp. 2882-2890 ◽  
Author(s):  
R. H. Al Anbari ◽  
S. M. Alfatlawi ◽  
J. H. Albaidhani
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Removal Efficiency ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Efficient Treatment ◽  
Electrolytic Cells ◽  
Removal Capacity ◽  
Metals Removal ◽  
Working Parameters

Heavy metal removal by electrocoagulation using iron electrodes material was investigated in this paper. Several working parameters, such as pH, current density and heavy metal ions concentration were studied in an attempt to achieve a higher removal capacity. A simple and efficient treatment process for removal of heavy metals is essentially necessary. The performance of continuous flow electrocoagulation system, with reactor consists of a ladder series of twelve electrolytic cells, each cell containing stainless steel cathode and iron anode. The treatment of synthetic solutions containing Zn 2+,Cu 2+,Ni 2+,Cr 3+,Cd 2+ and Co 2+ ,has been investigated. Results showed that iron is very effective as sacrificial electrode material for heavy metals removal efficiency and cost points. Also it was concluded that the chromium has lower efficient removal as compared to zinc, copper and nickel. At the same time cadmium and cobalt have minimum removal efficiency.

scholarly journals Using bioleaching to remove metals from sewage sludge intended for land application

2021 ◽  
Author(s):  
Jun Nie
Keyword(s):  
Heavy Metal ◽  
Sewage Sludge ◽  
Removal Efficiency ◽  
Agricultural Land ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Treatment Plant ◽  
Land Application ◽  
Sulphur Compounds ◽  
Recommended Level

Removal of heavy metal contaminants from sewage sludge is a necessity before it is used as an agricultural fertilizer (biosolid), due to environmental concerns and municipal, provincial and federal regulations. The bioleaching method is recommended as an economical and effective process for the removal of heavy metals from the Ashbridges Bay Treatment Plant (ABTP) sludge, some of them with concentrations exceeding the recommended level by the Ontario Ministry of Agriculture, Food, and Rural Affairs guidelines. The Gram-negative thiobacilli is a group of organisms with physiological and morphological similarity and grows by oxidizing ferrous ion and reduced sulphur compounds. One species of thiobacillus, T. ferrooxidan , was recommended as an effective bacterium for the heavy metal removal from sewage sludge. This research involved the incubation of adapted sludge using fresh raw digested sludge and activated sludge of ABTP. Using adapted sludge for the bioleaching process, the method was tested in a continuously stirred tank reactor (CSTR) in combination with a series of jar tests. Results showed that the metal removal efficiency increases with decreasing pH, and the solids content does not affect the removal efficiency of cupper and zinc very much during short term jar test. The results from the long-term (20-day) CSTR test demonstrated that the high T ferrooxians-contained adapted sludge could remove copper from the sewage sludge of ABTP very effectively, by as much as 79.2%. In comparison, the simultaneous removal efficiency of zinc and cadmium were also studied for the same process and, they are 82.0% and 83.9% respectively. The TSS degradation constant rate during the 20 days' bioleaching was found to be 0.0522 day -1. It is concluded that Ontario should continue to apply sludge to agricultural land, as sludge is an economic alternative, promotes recycling of resources, and is a valuable fertilizer. However, the toxic metals in sludge should be removed from sewage sludge using the bioleaching process to recommended level before it is disposed as a fertilizer for land application.

scholarly journals Comparison of the experimental results with the Langmuir and Freundlich models for copper removal on limestone adsorbent

2019 ◽  
Vol 9 (8) ◽  
Author(s):  
Thair Sharif Khayyun ◽  
Ayad Hameed Mseer
Keyword(s):  
Heavy Metal ◽  
Metal Ion ◽  
High Efficiency ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Equilibrium Concentration ◽  
Freundlich Isotherm ◽  
Isotherm Model ◽  
Batch Adsorption ◽  
Empirical Constant

Abstract The purpose of this study was to investigate the possibility of the limestone as an adsorbed media and low-cost adsorbent. Batch adsorption studies were conducted to examine the effects of the parameters such as initial metal ion concentration C0, particle size of limestone DL, adsorbent dosage and equilibrium concentration of heavy metal Ce on the removal of the heavy metal (Cu) from synthetic water solution by limestone. The removal efficiency is increased with the increase in the volume of limestone (influenced by the media specific area). It has been noted that the limestone with diameter of 3.75 is the most effective size for removal of copper from synthetic solution. The adsorption data were analyzed by the Langmuir and Freundlich isotherm model. The average values of the empirical constant and adsorption constant (saturation coefficient) for the Langmuir equation were a = 0.022 mg/g and b = 1.46 l/mg, respectively. The average values of the Freundlich adsorption constant and empirical coefficient were Kf = 0.010 mg/g and n = 1.58 l/mg, respectively. It was observed that the Freundlich isotherm model described the adsorption process with high coefficient of determination R2, better than the Langmuir isotherm model and for low initial concentration of heavy metal. Also, when the values of amount of heavy metal removal from solution are predicted by the Freundlich isotherm model, it showed best fits the batch study. It is clear from the results that heavy metal (Cu) removal with the limestone adsorbent appears to be technically feasible and with high efficiency.

scholarly journals Aquatic Mosses as Adaptable Bio-Filters for Heavy Metal Removal from Contaminated Water

2020 ◽  
Vol 21 (13) ◽  
pp. 4769
Author(s):  
Paride Papadia ◽  
Fabrizio Barozzi ◽  
Danilo Migoni ◽  
Makarena Rojas ◽  
Francesco P. Fanizzi ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Significant Proportion ◽  
Pollutant Removal ◽  
Polluted Water ◽  
Aquatic Moss ◽  
Aquatic Mosses ◽  
High Concentrations ◽  
Short Time

Heavy metals (HMs) are released into the environment by many human activities and persist in water even after remediation. The efficient filtration of solubilized HMs is extremely difficult. Phytoremediation appears a convenient tool to remove HMs from polluted water, but it is limited by the choice of plants able to adapt to filtration of polluted water in terms of space and physiological needs. Biomasses are often preferred. Aquatic moss biomasses, thanks to gametophyte characteristics, can act as live filtering material. The potential for phytoremediation of Hypnales aquatic mosses has been poorly investigated compared to aquatic macrophytes. Their potential is usually indicated as a tool for bioindication and environmental monitoring more than for pollutant removal. When phytoremediation has been considered, insufficient attention has been paid to the adaptability of biomasses to different needs. In this study the heavy metal uptake of moss Taxiphyllum barbieri grown in two different light conditions, was tested with high concentrations of elements such as Pb, Cd, Zn, Cu, As, and Cr. This moss produces dense mats with few culture needs. The experimental design confirmed the capacity of the moss to accumulate HMs accordingly to their physiology and then demonstrated that a significant proportion of HMs was accumulated within a few hours. In addition to the biosorption effect, an evident contribution of the active simplistic mass can be evidenced. These reports of HM accumulation within short time intervals, show how this moss is particularly suitable as an adaptable bio-filter, representing a new opportunity for water eco-sustainable remediation.

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