scholarly journals Crosslinked Carboxymethyl Sago Starch/Citric Acid Hydrogel for Sorption of Pb2+, Cu2+, Ni2+ and Zn2+ from Aqueous Solution

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2465
Author(s):  
Amyrah Auni Keirudin ◽  
Norhazlin Zainuddin ◽  
Nor Azah Yusof

In the present study, CMSS (carboxymethyl sago starch)-based hydrogel was synthesized by crosslinking with citric acid via esterification and then applied as a metal sorbent to overcome excessive heavy metal pollution. The CMSS/CA (carboxymethyl sago starch/citric acid) hydrogel was characterized by Fourier Transform Infrared (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and X-ray diffraction (XRD). The absorption band at 1726 cm−1 was observed in the FT-IR spectrum of CMSS/CA hydrogel and indicated ester bonds formed. Further findings show that the cross-linkages in the CMSS/CA hydrogel increased the thermal stability of CMSS and various sizes of pores were also shown in the SEM micrograph. Conversely, the removal of heavy metals was analyzed using Inductively Coupled Plasma-Optic Emission Spectra (ICP-OES). The effects of the pH of the metal solution, contact time, initial concentration of the metal ions and temperature on the sorption capacity were investigated. Under optimum condition, the sorption capacity of Pb2+, Cu2+, Ni2+ and Zn2+ onto CMSS/CA hydrogel were 64.48, 36.56, 16.21, 18.45 mg/g, respectively. The experiments demonstrated that CMSS/CA hydrogel has high selectivity towards Pb2+ in both non-competitive and competitive conditions. In conclusion, the CMSS/CA hydrogel as a natural based heavy metal sorption material exhibited a promising performance, especially in the sorption of Pb2+ for wastewater treatment.

2021 ◽  
Author(s):  
Ayat Nuri ◽  
Abolfazl Bezaatpour ◽  
Mandana Amiri ◽  
Nemanja Vucetic ◽  
Jyri-Pekka Mikkola ◽  
...  

AbstractMesoporous SBA-15 silicate with a high surface area was prepared by a hydrothermal method, successively modified by organic melamine ligands and then used for deposition of Pd nanoparticles onto it. The synthesized materials were characterized with infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), nitrogen physisorption, scanning electron microscopy (SEM) coupled with energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), nuclear magnetic resonance (NMR) and inductively coupled plasma (ICP-OES). The catalyst was effectively used in the Mizoroki–Heck coupling reaction of various reactants in the presence of an organic base giving the desired products in a short reaction time and with small catalysts loadings. The reaction parameters such as the base type, amounts of catalyst, solvents, and the temperature were optimized. The catalyst was easily recovered and reused at least seven times without significant activity losses. Graphic Abstract


2006 ◽  
Vol 118 ◽  
pp. 639-644
Author(s):  
Hye Sung Kim ◽  
Su Chak Ryu

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) powders is synthesized using the mixed powders of CaCO3 refined from oyster shells and phosphoric acid (H3PO4-98%, Daejung) as starting materials. The characteristic evaluation and chemical analysis of the synthesized powders is performed by X-ray diffraction (XRD), Fourier-transformed infra-red spectroscopy (FT-IR), and inductively-coupled plasma atomic emission spectroscopy (ICPAES). XRD analysis of synthetic powder by heat treatment at 1300°C for 2hrs shows only HAp peaks corresponding to stoichiometric HAp. It is confirmed by ICP-AES test that impurities such as Zn, In, Ti, Ba, Cd, Pb, and Mn, is not detected at all, but small amounts of Ti and Be is observed (0.099ppm Ti and 0.002ppm Ba). Variation of bone density is measured by giving medication of HAp powder with drinking water into human body continuously for three month. After the medication, the bone density is higher than the medication before. This means that HAp powder made from this process can be used as improver of bone density.


2021 ◽  
pp. 096032712199321
Author(s):  
M Charehsaz ◽  
S Helvacıoğlu ◽  
S Çetinkaya ◽  
R Demir ◽  
O Erdem ◽  
...  

In this study, the level of arsenic (As), lead (Pb) and cadmium (Cd) and also essential elements in beer samples consumed in Turkey were investigated using the inductively coupled plasma mass spectrometry (ICP-MS) method. The heavy metal-induced non-carcinogenic and carcinogenic risks were calculated. For essential elements, the calculated estimated daily intake of iron (Fe), copper (Cu), selenium (Se) and cobalt (Co) from beer consumption were compared with their toxicity reference values. Tukey post-hoc test showed that As was found at a significantly higher level when compared to Pb. Also, a significant correlation was found between As level and alcohol by volume percent. All samples had a hazard quotient and hazard index <1, indicating no non-carcinogenic risk from exposure to single or multiple heavy metals. Some samples exceeded the threshold limit of acceptable cancer risk for As in the high beer consumer group. This assessment showed that in addition to health implications based on the alcohol content of beer, there might be a carcinogenic risk associated with the heavy metals content of these beverages.


2015 ◽  
Vol 43 (1) ◽  
pp. 7-14 ◽  
Author(s):  
György Heltai ◽  
Ilona Fekete ◽  
Gábor Halász ◽  
Katalin Kovács ◽  
Márk Horváth ◽  
...  

Abstract For the characterisation of the environmental mobility of heavy metal contamination in aquatic sediments, the EU Bureau of Reference has proposed a fractionation by sequential extraction procedure. For its validation, the CRM-701 sample is available containing Cd, Cr, Cu, Ni, Pb, and Zn. In this paper, the matrix-matched calibration problems are presented. A multi-elemental inductively coupled plasma-optical emission technique is employed for the detection of heavy metals in the extracts. It was established that the sensitivities are strongly influenced by the extractants, which causes significant matrix effects: the sensitivities are strongly influenced by the solvents applied in extraction steps; the summarised recoveries show an acceptable agreement with the certified values; however, in the individual extraction steps for certain elements significant differences may occur due to the neglected interferences. Therefore, further optimisation is required utilising the flexible line selection possibility offered by the HORIBA Jobin Yvon ACTIVA-M instrument.


2021 ◽  
Author(s):  
Soni Kumari ◽  
Amarnath Mishra

In the era of industrialization, pollution has totally deteriorated the quality and diversity of life. Heavy metal contaminations are the major causes of environment deteriorations. The basic reasons are natural as well as anthropogenic. Chief sources of heavy metal contamination are air pollution, river sediments, sewage sludge, town waste composts, agricultural chemicals like fertilizers and pesticides, and industrial waste like factories releasing chemicals, anthropogenic activities, etc. Agricultural soils in many parts of the world are generally contaminated by heavy metal toxicity such as Cd, Cu, Zn, Ni, Co, Pb, Hg, As, etc. These are due to the long-term use of phosphate fertilizers, sewage sludge, dust from smelters, industrial waste, etc. Heavy metals in soils are detected with some specific instruments like atomic absorption spectroscopy, inductively coupled plasma, inductively coupled plasma-mass spectroscopy, and X-ray fluorescence and spectroscopy. Among all these instruments, atomic absorption spectroscopy (AAS) is the best because it gives the precise quantitative determination. AAS is a method applied for measuring the quantity of the trace elements present in the soil or any other samples.


Author(s):  
Anna Schild ◽  
Julie Cool

Waste wood collected at the Vancouver landfill has been sorted based on the visibility of coatings, paints, and the green colorization of wood typically associated with wood preservatives. The sorted material was then ground and tested with an inductively coupled plasma mass spectrometry (ICP–MS) for heavy metal elements that are toxic or harmful to humans and (or) the environment. Results indicated that wood preservatives were not visually detectable but paints and coatings were. Therefore, the study demonstrated that visual sorting is not sufficiently accurate to distinguish between treated and clean or untreated waste wood.


1985 ◽  
Vol 7 ◽  
pp. 175-180 ◽  
Author(s):  
S. Landsberger ◽  
R.E. Jervis

Three multi-elemental techniques (neutron activation analysis, proton-induced X-ray emission and inductively coupled plasma-atomic emission spectrometry) are described in terms of their special advantages in determining sulphur and heavy metal pollution in urban snow. Environmental analytical interpretations, including wash-out factors, enrichment factors, inter-elemental correlations, mobilization factors, and toxicity potential, are also discussed.


1985 ◽  
Vol 7 ◽  
pp. 175-180
Author(s):  
S. Landsberger ◽  
R.E. Jervis

Three multi-elemental techniques (neutron activation analysis, proton-induced X-ray emission and inductively coupled plasma-atomic emission spectrometry) are described in terms of their special advantages in determining sulphur and heavy metal pollution in urban snow. Environmental analytical interpretations, including wash-out factors, enrichment factors, inter-elemental correlations, mobilization factors, and toxicity potential, are also discussed.


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