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Eco-friendly magnetic biochar from Leb Mu Nang banana peel: Response surface methodology optimization for Cd(II) adsorption from synthetic wastewater
(2024-02-01)
Limmun, Wanida
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Limmun, Warunee
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Borkowski, John J.
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Ishikawa, Nao
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Pairintra, Rattanachai
Magnetic biochar derived from Leb Mu Nang banana peel waste is introduced as a novel precursor for Cd(II) removal from synthetic wastewater. This study comprehensively evaluates and optimizes variable factors, including initial Cd(II) concentration, magnetic biochar (MLP) dosage, adsorption time, and initial pH level, using the Response Surface Methodology (RSM). A Cd(II) removal efficiency of up to 93.4 % is reached under the conditions of a 50 mg/L initial concentration, 5 g/L MLP dosage, 24 h of adsorption time, and a solution pH of 8. The pseudo-second-order and Langmuir models accurately represent the kinetics and isotherm adsorptions, highlighting ion exchange, surface complexation, and precipitation as primary adsorption mechanisms. The magnetic biochar derived from Leb Mu Nang banana peels shows promise for efficient Cd(II) removal with easy post-adsorption separation.
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The Influence of Chemical Fertilizers on the Effectiveness of Biochar in Mitigating Cadmium Mobility in Soil
(2024-01-01)
Chaiyaraksa, Chompoonut
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Sangworn, Navapat
The focus of this study was to explore how various fertilizers influence the movement of cadmium in soil treated with biochar. The research utilized a strong acid sandy loam soil from Chanthaburi Province, naturally rich in organic matter with moderate cation exchange capacity and low nitrogen, potassium, phosphorus, sulfate, salinity and chloride levels. The soil was purposely contaminated with 50 mgkg-1 of cadmium and treated with biochar derived from water hyacinth through pyrolysis at 450°C for an hour. This biochar displayed moderate alkalinity, high organic matter, phosphorus, potassium, and cation exchange capacity, but low nitrogen content. Analytical techniques like Scanning Electron Microscopy and Fourier-Transform Infrared Spectroscopy were employed to study the surface characteristics of the biochar. The cadmium adding soil was blended with 10% biochar and various chemical fertilizers at a 0.04% ratio. Diethylenetriamine pentaacetate (DTPA) extraction was used to assess the bioavailability of cadmium to plants in the soil, while sequential extraction was conducted to identify the different forms of cadmium present in the soil. The study revealed distinct effects of different fertilizers on cadmium mobility. Fertilizers like 46-0-0 and 0-3-0 caused a transformation of cadmium from stable to less stable forms, increasing the bioavailability of cadmium to plants. Conversely, fertilizers such as 15-15-15, 0-0-50, 0-0-60, and 0-52-34 shifted cadmium from less stable to more stable forms, resulting in decreased cadmium extracted by DTPA. Other fertilizers showed no significant impact on cadmium mobility in the soil. A stepwise linear regression analysis highlighted that nitrogen content, potassium content, and electrical conductivity were influential factors affecting cadmium mobility.
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Immobilization of cadmium in soil using magnetic biochar derived from Eichhornia crassipes
(2020-08-01)
Chaiyaraksa, Chompoonut
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Lokham, Nongnapa
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Kuikrong, Rawisara
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Artsanapaiboon, Sangarun
Heavy metal contamination in an environment is a critical problem in Thailand that needs to be addressed urgently, particularly contaminated soil. This research aims to study the adsorption of cadmium ion by unmodified biochar and sodium dodecyl sulfate modified magnetic biochar (SDS-MB) derived from Eichhornia Crassipes. The adsorbent and soil characteristics were determined. Observed by scanning electron microscope (SEM), the surface of unmodified biochar (B) was smoother than SDS-MB. The X-ray diffractometer (XRD) pattern showed peaks for iron oxide. The values of point of zero charge (pH<inf>PZC</inf>) and acid neutralization capability (ANC) were 3 and 1000.3 meq/kg, respectively. The greatest adsorption of cadmium occurred when the pH of the wastewater was 8. The adsorption reached equilibrium within 1 h. It followed Freundlich, Temkin, and Dubinin-Radushkevich isotherm model and the pseudo-second-order kinetic. SDS-MB was mixed with sandy clay loam soil (pH 7.87) contaminated with cadmium 50 mg per kilogram soil at the ratio of 0-5%. The results from the extraction with ethylenediaminetetraacetic acid (EDTA), ammonium acetate, calcium chloride, diethylene triamine pentaacetic acid (DTPA), and sequential extraction method indicated that 5% mixing ratio showed the best ability to reduce cadmium movement in the soil. Cadmium in a form that bound to oxide and a form that bound to organic matter significantly increased.
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Variations of grain iron and zinc concentrations among the promising low-grain cadmium rice (Oryza sativa l.) cultivars
(2020-03-01)
Sriprachote, Anongnat
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Manantapong, Kanokporn
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Kanyawongha, Pornthiwa
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Ochiai, Kumiko
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Matoh, Toru
We aimed to clarify whether low cadmium (Cd) accumulation in varieties of rice also lower human nutrient uptakes. This trial was setup to explore the correlation between grain-Cd and iron (Fe) and zinc (Zn) among four promising rice cultivars and the prevailing KDML105 and RD6. Their grain Cd (0.10–0.60 mg kg-1) and Zn (17.36–22.61 mg kg-1) contents were signi-ficantly different, but not significant for grain Fe (11.17–13.91 mg kg-1). The results revealed significant positive correlations between grain Cd and Zn of the prevailing cultivar (r=0.471). But no correlations between grain Cd and Fe and Zn were observed. The RD15 and KNU2 were identified as the low grain Cd, high grain Fe and Zn compared with the prevailing cultivar. Thus the RD15 and KNU2 led to reduced Cd in rice grain without changing the human essential elements.
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Six years monitoring of the promising low grain-Cd accumulating rice, RD15 cultivar grown on Cd-contaminated paddy soils
(2020-01-01)
Sriprachote, Anongnat
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Kanyawongha, Pornthiwa
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Boonplang, Nutcharee
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Phanchindawan, Naree
The experiment was conducted on the Cd-contaminated paddy field, two of Thai rice cultivars, the prevailing KDML105 and RD15 were included together with determining grain-Cd accumulation. The results had revealed that the RD15 contained Cd in grains not only lower than KDML105 but also lower than the critical level as proposed by Codex (0.4 mg kg-1 polished rice). Thus, the RD15 was selected as the promising low grain-Cd accumulating rice cultivar, and farmers were encouraged to grow this cultivar. The grains of prevailing and promising rice cultivars were annually collected for Cd analysis. After six-years monitoring, the results revealed that the average concentration of Cd in KDML105 was 0.658 mg kg-1, which exceeded the critical level. On the other hand, the average concentration observed in RD15 (0.127 mg kg-1) was lower than the critical level. The human dietary intake of Cd through rice consumption was calculated, comparing to the provisional tolerable weekly intake (PTWI) as adopted by FAO/WHO (7 ug Cd kg-1 BW per week), the PTWI of KDML105 was far exceeded the critical level. Contrary, the RD15 had the PTWI lower than the critical level. Present results indicated that, by cultivating RD15 the promising low-grain Cd cultivar, Cd intake together with health risk of human could be reduced.
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Application of biochar for enhancing cadmium and zinc phytostabilization in vigna radiata L. cultivation
(2014-12-01)
Prapagdee, Songkrit
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Piyatiratitivorakul, Somkiat
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Petsom, Amorn
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Tawinteung, Nukoon
Cadmium (Cd) is a toxic and nonessential element. Because of its toxicity, Cd soil contamination is a major environmental risk to living organisms. Several studies have reported on the successful use of biochar to immobilize Cd in soil as it reduces Cd accumulation in plant parts. This research reports on the contrasting effect of biochar on enhancing Cd uptake by plants. A cassava stem biochar produced through low-temperature pyrolysis was applied to natural Cd-contaminated soil that also had a high zinc (Zn) concentration. Vigna radiata L. (a green bean) was grown in treatments receiving three biochar rates, i.e., 5, 10, and 15 %, respectively. The results showed that the 10 % biochar-amended soil had a positive effect on promoting plant growth and seed yield. Unfortunately, 15 % biochar-amended soil caused an adverse effect to plant growth. Cadmium uptake by plants increased with increasing biochar application rate. Zinc uptake by plants tended to decrease with biochar application. Cadmium and Zn bioavailability in soil was significantly reduced with an increasing biochar application rate. The results also showed that the biochar-amended soil could be an alternative and cost-effective method to promote plant growth and decrease Cd mobility in soil. The ratio of Cd concentration in plant root to soil was higher than 1, while the translocation factor from root to shoot was less than 1. These results indicate that the cultivation of V. radiata L. coupled with biochar application is an appropriate method to enhance Cd phytostabilization efficiency of V. radiata L. in Cd-polluted sites.
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Current situation of cadmium-polluted paddy soil, rice and soybean in the mae sot district, tak province, thailand
(2012-01-01)
Sriprachote, Anongnat
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Kanyawongha, Pornthiwa
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Ochiai, Kumiko
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Matoh, Toru
Since 2002, a joint research team from the International Water Management Institute and the Department of Agriculture, Thai Government, has reported that there are cadmium (Cd)-contaminated paddy fields in northern Thailand. We evaluated the current situation of the Cd-polluted paddy fields in this report. Home-consumed rice grains were collected from all 23 households in the village of Pha Te, Mae Sot District of Tak Province, Thailand. The Cd concentration in unhusked rice (Oryza sativa L.) grains ranged from 0.04 to 1.75 mg Cd kg1, and the rice of more than half of the households contained Cd levels higher than the critical level of 0.4 mg Cd kg1 polished rice, which is CODEX standard. Among the paddy fields, we selected one plot (1.2 ha) and analyzed Cd concentrations of the soil, and rice and soybean (Glycine max L.) grains. In this area, a rotation cropping system of wet-season rice and dry-season soybean is common practice. The soil Cd concentration ranged from 0.31 to 13.9 mg Cd kg1 (total Cd) and 0.030 to 13.3 mg Cd kg1 [extracted with 0.1 M hydrochloric acid (HCl)], the Cd concentration in the rice grains ranged from 0.12 to 1.27 mg Cd kg1, and that in the soybean grains ranged from 0.07 to 0.80 mg Cd kg1. The soil extractable Cd concentration was well reflected in the soybean grain Cd levels (r2 ¼ 0.581), but not in the rice grain levels (r2 ¼ 0.015), suggesting that rice grain Cd levels are influenced not only by the soil Cd concentration, but by other factors as well, such as soil water regime and soil pH. However, a significant difference in the grain-Cd concentration was found; that is, lower Cd in the cultivar ‘‘Khao’ Khaeng’’ and higher in the ‘‘Khao Dawk Mali 105’’, which suggests a possibility of selecting a rice cultivar having low-grain Cd.
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Cadmium content of commercial and contaminated rice, Oryza sativa, in Thailand and potential health implications
(2010-03-01)
Zwicker, R.
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Promsawad, A.
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Zwicker, B. M.
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Laoharojanaphand, S.
Thailand is the number one global exporter and among the top five producers of rice in the world. A significant increase in anthropogenic contamination in agricultural soils over the past few decades has lead to concerns with cadmium and its uptake in rice. The cadmium levels in Thai rice from different sources/areas were determined and used to estimate the potential health risks to consumers. The cadmium concentration in the commercial rice samples ranged from below the detection limit to 0.016 mg/kg. The cadmium concentrations in the contaminated rice samples ranged from a low of 0.007 mg/kg to a high of 0.579 mg/kg. Five of the calculated values exceed the proposed PTWI, with one value almost three times higher and two values almost double. The three highly elevated values are certainly a concern from a health standpoint. Ultimately, action is required to address the health implications resulting from the cadmium contamination in agricultural soils used for rice production in a few select areas of Thailand. Overall, this study indicates that the vast majority of rice produced, consumed and exported by Thailand is safe pertaining to cadmium content. © 2009 Springer Science+Business Media, LLC.
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Evaluation of phosphate fertilizers for the stabilization of cadmium in highly contaminated soils
(2009-06-15)
Thawornchaisit, Usarat
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Polprasert, Chongrak
The efficiency of three phosphate fertilizers including triple superphosphate (TSP), diammonium phosphate (DAP), and phosphate rock (PR) as stabilizing agents of cadmium-contaminated soils has been assessed in this study. Two types of assessment criteria, (a) the reduction of leachable cadmium concentration; and (b) the changes in Cd association with specific operational soil fraction based on the sequential extraction data, are used in the evaluation of stabilization performance of each fertilizer. Results of the study showed that after the 60-day stabilization, the leachable concentrations of Cd in PR-, DAP- and TSP- treated soils reduced from 306 mg/kg (the control) to 140, 34, and 12 mg/kg with the stabilization efficiency as TSP>DAP>PR. Results from the assessment of Cd speciation via sequential extraction procedure revealed that the soluble-exchangeable fraction and the surface adsorption fraction of Cd in the soils treated with PO<inf>4</inf> fertilizers, especially with TSP, have been reduced considerably. In addition, it is found that the reduction was correspondingly related with the increase of more stable forms of cadmium: the metal bound to manganese oxides and the metal bound to crystalline iron oxides. Treatment efficiency increased as the phosphate dose (based on the molar ratio of PO<inf>4</inf>/Cd) increased. In addition, it was observed that stabilization was most effective when using the molar ratio of PO<inf>4</inf>/Cd at 2:1 and at least 21-day and 28-day stabilization time for TSP and DAP, respectively. © 2008.
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Bioaccumulation of cadmium in an experimental aquatic ecosystem involving phytoplankton, zooplankton, catfish and sediment
(2007-01-01)
Raungsomboon, Suneerat
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Wongrat, Ladda
The accumulation of cadmium (Cd) was studied in an experimental aquatic ecosystem involving the phytoplankton, Chlorella regularis, the zooplankton, Moina macrocopa, and the catfish, (cross bridge Clarias macrocepharus X Clarias gariepinus), and sediment. All organisms were selected in this study because of their economically importance. The accumulation of cadmium was mainly on phytoplankton. The cadmium concentration in all organisms increased with increasing cadmium concentration in the ecosystem. When the input cadmium concentration was 3.5 mg l-1, cadmium accumulated in the surface of sediment (0-1 cm.), phytoplankton, zooplankton, and catfish were 5.53±0.26, 586.18±23.37, 141.52±26.74 and 10.29±0.47 μg g-1 (dry wt.), respectively. Results showed that phytoplankton, zooplankton, and catfish exposed to cadmium represents a risk of secondary poisoning for their predators and such a risk could affect humans. The accumulation of cadmium in sediment may have an effect on benthic organisms.

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