Removal of Cr(III) ions from water and wastewater by sorption onto peats and clays occurring in an overburden of lignite beds in central Poland

Abstract

Sorption capacities of low-moor peats and Neogene clays from the overburden of lignite beds in Central Poland for Cr(III) ions as chloride and metalorganic complex ions have been investigated. The binding mechanisms and sorption parameters were determined based on the Freundlich and Langmuir nonlinear sorption isotherms. The sorption capacities of studied materials for Cr(III) ions depended on their properties (porosity, average pore diameters, specific surface area and content of Fe hydroxyoxides) as well as charge of Cr(III) ions, functional groups and their diagonal lengths. Cr(III) ions from chlorides were bound onto sorbents via Coulomb attraction and by Fe hydroxyoxides. However the complex Cr(III) ions were bound to the sorbent surface via hydrogen bonds between the dye -OH groups and =O of the sorbent functional groups. The equation parameters of sorption isotherms indicate cooperative heterogeneous adsorption at low Cr(III) concentrations and chemisorption at high Cr(III) concentrations.

Smectitic clays enriched with ferric ions for the rapid removal of anionic dyes in aqueous media

“…The FTIR spectra of Argel and Volclay (Fig. 4) are consistent with previously reported spectra of smectite clays (Santos et al, 2002;Mariani et al, 2013;Kyzioł-Komosińska et al, 2014). These spectra include bands at 990 cm -1 (Si-O-Si asymmetric stretching), 912 cm -1 (Al-OH-Al deformation vibrations), 795 cm -1 (Si-O-Al vibrations with substitution of Si by Al at the tetrahedral site), 513 cm -1 (Si-O-Al vibrations with Si at the tetrahedral site and Al at the octahedral site), 455 cm -1 (Si-O-Si angular deformation) and 619 cm -1 (Al-O and Si-O bonds).…”

Removal of chromium (VI) from aqueous solution using vesicular basalt: A potential low cost wastewater treatment system

“…1 a. The band in the region 3000–3700 cm −1 , maximum peak at 3430 cm −1 was due to −OH symmetric stretching vibration and in the region 1600–1700 cm −1 a maximum peak at 1634 cm −1 was fundamental bending vibrations of H-OH [ 27 , 48 ]. The spectral features displayed in the reststrahlen band region (1200–800 cm −1 ) revealed more overlap and are comparable to mineral features in the range of silica polymerization such as plagioclase, pyroxene and olivine ( Fig.…”

“…An adsorbent is considered as a low cost if it requires little processing, abundant in nature and is a by-product or waste material resulting from an industry [26] . Several low cost adsorbents including clays [ 27 , 28 , 29 , 30 ], industrial by-products [ 31 , 32 ], agricultural wastes [ 33 , 34 ], biomass [35] , and polymeric materials [36] , and young vesicular volcanic rocks [37] have been investigated for Cr (VI) removal.…”

Fraction Of Heavy Metals In Sludges From Typical Coking Wastewater Treatment Plants By Modified Bcr Sequential Extraction Procedure

“…Heavy metals are concerned contaminants due to the high toxicity and nonbiodegradability. The speciation of heavy metals determined the biodegradability and the toxicity [1,2]. Many factors could affect the speciation of metals such as pH, concentration of sulfide and inorganic phosphate in soil and sludge [3].…”

“…_________________________ 1 The Key Laboratory of Pollution Control and Ecosytem Restoration in Industry Cluster, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou, China, 510006. 2 School of Environment and Planning, Liaocheng University, Liaocheng, China, 252059, corresponding author C. H. Wei, e-mail address: cechwei@scut.edu.cn Different speciation of heavy metals in soil, sludge and sediment is distinguished by means of specific solvents [4]. Based on different solvents, numerous methods were proposed to assess the actual toxicity of heavy metals [5][6][7].…”