Fabrication of β-cyclodextrin/poly ( l -glutamic acid) supported magnetic graphene oxide and its adsorption behavior for 17β-estradiol

J of Chemical Tech & Biotech

et al. 2017

Self Cite

BACKGROUND This article reports the synthesis and characterisation of titanium dioxide‐coated biochar composites (TBCs) by pyrolysing titanium dioxide‐treated biomass prepared by a modified sol–gel method. Their adsorptive and photocatalytic activities were evaluated based on the removal of safranine T (ST) from an aqueous solution with/without UV‐light irradiation. RESULTS Characterisation studies suggested that TiO2 was successfully loaded on the biochar substrate. The biochar and TiO2 contents of the composite significantly affected its performance. The ST removal capabilities of the TBCs with 1, 1.5, 2, and 2.5 g of the biomass are 1.7, 2.3, 7.2, and 2.3 times better than that of the raw biochar, respectively. Thus, the optimum amount of biomass in TBC‐x was determined to be 2 g, with the corresponding sample exhibiting excellent stability, effectiveness over a wide pH range, and a maximum ST removal capacity of 226.7 mg g‐1. CONCLUSION The loading of TiO2 significantly enhanced the adsorption performance of biochar and the high specific surface area of the biochar synergistically promoted the photocatalytic activity of TiO2. Both adsorption and photocatalytic degradation were confirmed to contribute to the decolourisation of the aqueous solution because of the removal of ST, with the effect of adsorption being slightly higher than that of photocatalysis. The synthesised composite is a promising alternative material for removing chemical contaminants. © 2017 Society of Chemical Industry

“…Based on the XRD results, the crystal size of the microspheres was determined using Scherrer's formula:

L = \frac{italicK λ}{β \cos normalθ}

Section: Resultsmentioning

confidence: 99%

“…The specific surface area and total pore volume of raw BC are 3.29 m 2 g -1 and 0.007 cm 3 g -1 , which increased to 10.55 m 2 g -1 and 0.019 cm 3 g -1 , respectively, for the TBC-2 nanocomposite. Based on the XRD results, the crystal size of the microspheres was determined using Scherrer's formula 33 :…”

Section: Characterisation Of the Compositesmentioning

confidence: 99%

Titanium dioxide‐coated biochar composites as adsorptive and photocatalytic degradation materials for the removal of aqueous organic pollutants

Cai

Jiang

J of Chemical Tech & Biotech

et al. 2017

Self Cite

“…and the parameters calculated from the two isotherm models are listed in Table . The Langmuir model is used to describe homogeneous adsorption systems in which adsorption occurs at a homogeneous surface via a monolayer and equivalent adsorption, while the Freundlich isotherm is adapted to heterogenous adsorption without being limited to the formation of a monolayer . Comparing the values of R 2 for the two models, the adsorption isotherms of three antibiotics were different.…”

Section: Resultsmentioning

confidence: 99%

Comparative study of rice husk biochars for aqueous antibiotics removal

Zeng

Tian

J of Chemical Tech & Biotech

et al. 2017

BACKGROUND Antibiotics are widely used for the treatment of bacterial infections in humans and animals, but it can be released into water sources due to incomplete metabolism in humans or via discharge from drug manufacturers. RESULTS The efficiency of removal of three antibiotics was enhanced with increasing biochar dosage. The adsorption of three antibiotics by RH700 was much higher than by RH300 and RH500, which might be due to the larger surface area and adsorption pore volume of RH700 (211.76 m2 g‐1 and 6.25 nm, respectively). In addition, the adsorption capacity was greatly affected by the solution pH, background electrolyte and humic acid. The kinetics experiment data were well fitted by the pseudo‐second‐order kinetic model. The maximum adsorption capacities of tetracycline hydrochloride (TC), doxycycline hydrochloride (DC) and ciprofloxacin (CF) based on the Langmuir model by RH700 at 318 K were 80.9, 85.2 and 36.1 mg g‐1, respectively. RH700 exhibited high affinity for antibiotics, mainly ascribed to the chemical interaction between oxygen‐containing functional groups (phenolic hydroxyl group, carboxyl and alkoxy groups) of the biochar surface and TC, DC and CF. CONCLUSION The rice husk biochar produced at high temperature could be applied as a potential adsorbent for removal of antibiotics from water. © 2017 Society of Chemical Industry

“…Endocrine-disrupting chemicals (EDCs), widely existing in water in the environment as well as in drinking water, 1 have gained growing concern in recent years. EDCs are classied into natural and synthetic estrogens, such as 17b-estradiol (E2) and 17a-ethynylestradiol (EE2), respectively.…”

Section: Introductionmentioning

confidence: 99%

Hydrothermal synthesis of montmorillonite/hydrochar nanocomposites and application for 17β-estradiol and 17α-ethynylestradiol removal

Tian

et al. 2018

RSC Adv.

abWith a view to reducing estrogens pollution in aqueous environments, montmorillonite/hydrochar (MMT/ HC) with or without modification by KOH via hydrothermal carbonization process (HTC) were applied to remove 17b-estradiol (E2) and 17a-ethynylestradiol (EE2). The characterizations of MMT/HC indicated that MMT had been successfully attached onto HC surface, which could cause an improvement in the stability of the clay nanoparticles. MMT/HC with 1% KOH (MMT/HC-K1) exhibited excellent adsorption) compared to those of other adsorbents; approximately 2-fold higher than that of HC. Moreover, the adsorption capacity maintained a high level over a wide pH range (2-8). The pseudo-second-order model and Freundlich model exhibited prior fitting performance for adsorption of E2 and EE2. The regenerated MMT/HC-K1 retained over 80% of its initial capacity after four cycles. The adsorption mechanism on MMT/HC-K1 could be explained by hydrophobicity, p-p bond, electrostatic interaction and H-bonding interaction. Overall, MMT/HC-K1 synthesis from two low-cost materials, could be considered as a competitive adsorbent for estrogens removal from aqueous environment, considering its high adsorption capacity and regeneration ability.