Nanomaterials for Removal and Speciation of Chromium

Overview

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Key numbers

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• Citation: Pyrzynska, K. chromium in drinking water are 20 µg/L and 50 µg/L, respectively (7).
• maximum sorption of Cr(V) onto MWCNTs (~450 mg/kg) was determined for sample pH
• of 250 mg/L (46). For a pH higher than the PZC, the sorption rapidly decreased since the
• chromium concentration (11 mg/L), the value for Cr(VI) maximum sorption (~10 mg/kg)
• a fast Cr(VI) sorption rate, achieving 95% removal within 3 min at pH 4 (56). PA-MWCNTs
• juice (OJMW) was proposed by Amaku and Taziwa (57). Orange juice, which was used as
• cess with 0.5 M NaOH. A removal efficiency of over 70% was observed after
• A removal efficiency of over 70% was observed after the fourth adsorption–desorption the fourth
• for Cr(VI) removal (65). Using a solution with a 10 mg/L concentration and pH 2, an
• adsorption efficiency of 87% was achieved with only 5 mg of this nanocomposite. The
• decrease its concentration from 9.9 mg/L to below 0.05 mg/L within 50 s with an adsorbent
• at an equivalent concentration (~50 mg/L)
• at an equivalent concentration (~50 mg/L) (86). (86). This suggests
• reached 182.43 mg/g. CS@SiO2 @TiO2 demonstrated over 90% removal efficiency for Cr(VI)
• 182.43 mg/g. CS@SiO2@TiO2 demonstrated over 90% removal efficiency for Cr(VI) from
• removal of Cr(VI) ions. Table 1 presents their recently reported performances. The results
• Table 1. Examples of the recent application of nanomaterials for Cr(VI) removal.
• SBET of Cr(VI) ions. Table 1 presents their recently reported
• GO@SiO2 _ 3 24 h 92.3% removal (66)
• GO@SiO2 _ 3 24 h 92.3% removal (66)
• removal of Cr(III) from a real effluent sample with a concentration of 3477.5 mg/L (91).
• 51.88%. Cr(III) adsorption on the graphene oxide surface was attributed mainly to elec-
• nanocomposite (92). However, Cr(III) ion removal decreased from 91% to 43% after five
• nanomaterials are presented in Table 2. The high adsorption capacity of the adsorbent
• to the desorption process (15 min) (23). As can be seen from Table 2, the addition of aniline
• parison to the desorption process (15 min) (23). As can be seen from Table 2, the addition
• range of 2.5–7 for Cr(III) and 2.5–3.5 for Cr(VI). Under an
• Fe3 O4 @PANI 8 5 0.2% TU + 2 M HCl 80 (99)
• Fe3 O4 @PANI-PTh 10 5 0.2% TU + 1 M HNO3 38.5 (100)
• Table 2. Examples of recent procedures for chromium speciation using nanomaterials.
• MWCNTs@CuAl2 O4 @SiO2 5 Conditions 3 M HNO3 in 10% acetone 17 (102)
• NiO/NiFe2 O4 /LDH 6 15 10% (NH4 OH)Cl 250 (105)
• Fe3O4@PANI-PTh 10 5 0.2% TU + 1 M HNO3 38.5 (100)
• 10% (NH was adjusted to pH 3 and
• monium range of 20–800
• solution (3 mL) in 10% acetone was used for its elution. Complexes of chromium with
• species. In most cases, recoveries for both ions above 95% were achieved, indicating the
• adsorbent for efficient removal of Cr(VI) and Hg(II) from aqueous solutions under wide pH range. J. Hazard. Mater. 2021,
• 70. Bao, S.; Yang, W.; Wang, Y.; Yu, Y.; Sun, Y. Highly efficient and ultrafast removal of Cr(VI) in aqueous solution to ppb level by
• affinity to Congo red, methyl orange and Cr(VI) ions. J. Hazard. Mater. 2019, 369, 214–222. (CrossRef) (PubMed)

Methods (brief)

• Chromium speciation in different environmental samples usually involves distinguish-
• plasma mass spectrometry (ICP MS) offers a low detection limit, matrix interferences and
• Additionally, factors such as sample pH, sorbent dosage, analyte concentration, extraction
• groups, influence adsorption efficiency. In addition, sample pH affects sorption yields by
• The adsorption process is more efficient when the sample’s pH is higher than the
• the sampleinformation
• maximum sorption of Cr(V) onto MWCNTs (~450 mg/kg) was determined for sample pH
• Nanomaterial 2 Sample pH Contact Time Ref.
• GO@AHMT 32 Sample100pHmin Contact Time 734.2 Ref.
• Nanomaterial Sample pH Contact Time Ref.
• removal of Cr(III) from a real effluent sample with a concentration of 3477.5 mg/L (91).
• used permits a large sample volume to be uploaded and consequently achieves a good
• lower detection limit for GFAAS detection, while modification with aminosalicylic acid
• Selective sorption of Cr(III) ions (Figure 7). The second subsample was adjusted to pH 3 and sonicated with 10 mg of
• EF—enrichment factor (ratio of the sample volume to eluent volume); TYR—tyrosine; ASA—aminosalicylic acid;
• NiO/NiFe2O4/LDH Cr(III) ions 6(Figure 7). The 15second subsample
• but at a sample pH of 5. In another work, Cr(VI)-APDC chelates were adsorbed onto a
• Successful examples of chromium speciation in environmental water and soil samples

Implications

This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.

Wiki pages this source may touch

• Baby Sunscreen, Mineral (ZnO + TiO2)
• Nickel
• Chromium

Verification notes

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Update history

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