Oil removal from oily water by a low-cost and durable flexible membrane made of layered double hydroxide nanosheet on cellulose support

A three-dimensional Ni–Fe layered double hydroxide/graphene hybrid aerogel (Ni–Fe LDH/GHA) was synthesised and used as a high performance supercapacitor electrode material.

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Ni-Based Catalyst Derived from NiAl Layered Double Hydroxide for Vapor Phase Catalytic Exchange between Hydrogen and Water

Nanomaterials ◽

10.3390/nano9121688 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1688 ◽

Cited By ~ 1

Author(s):

Xiaoyu Hu ◽

Peilong Li ◽

Xin Zhang ◽

Bin Yu ◽

Chao Lv ◽

...

Keyword(s):

Layered Double Hydroxide ◽

Vapor Phase ◽

Active Sites ◽

Low Cost ◽

Isotope Separation ◽

Nickel Catalysts ◽

Dissociative Chemisorption ◽

High Efficient ◽

Double Hydroxide ◽

Catalytic Exchange

A high-efficient and low-cost catalyst on hydrogen isotope separation between hydrogen and water is an essential factor in industrial application for heavy water production and water detritiation. In past studies, Pt-based catalysts were developed but not practical for commercial use due to their high cost for vapor phase catalytic exchange (VPCE), while for impregnated nickel catalysts with a lower cost the problems of agglomeration and low Ni utilization existed. Therefore, to solve these problems, in-situ grown Ni-based catalysts (NiAl-LDO) derived from a layered double hydroxide (LDH) precursor were fabricated and first applied in VPCE in this work. Compared with traditional impregnated Ni-based catalysts, NiAl-LDO catalysts own a unique layered structure, homogeneous dispersed metallic phase, higher specific surface area as well as stronger metal-support interactions to prevent active metal from agglomerating. These advantages are beneficial for exposing more active sites to improve dynamic contacts between H2 and HDO in a catalyst surface and can bring excellent catalytic activity under a reaction temperature of lower than 400 °C. Additionally, we found that the dissociative chemisorption of HDO and H2 occurs not only in Ni (111) but also in NiO species where chemisorbed H(ads), D(ads), OH(ads) and OD(ads) are formed. The results highlight that both of the Ni2+ species and Ni0 species possess catalytic activities for VPCE process.

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Advances in layered double hydroxide-based ternary nanocomposites for photocatalysis of contaminants in water

Nanotechnology Reviews ◽

10.1515/ntrev-2020-0102 ◽

2020 ◽

Vol 9 (1) ◽

pp. 1381-1396

Author(s):

Hao Sun ◽

Young-Jung Heo ◽

Ji-Hye Park ◽

Kyong Yop Rhee ◽

Soo-Jin Park

Keyword(s):

Layered Double Hydroxide ◽

Heavy Metal Ions ◽

Photocatalytic Performance ◽

Low Cost ◽

Aqueous Media ◽

Energy Crisis ◽

Electron Hole ◽

Light Utilization ◽

Double Hydroxide ◽

Photocatalytic Applications

Abstract Recently, photocatalysis technology has been widely considered as an effective method for solving environmental pollution issues and addressing the energy crisis. Hybrids of layered double hydroxide (LDH) exhibit excellent photocatalytic properties for use in the field of wastewater treatment due to the large interlayer spaces, chemical stability, and low cost. However, pristine LDH suffers from numerous limitations, such as insufficient visible light utilization and a high recombination rate of electron–hole pairs, resulting in degradation of photocatalytic performance. Recent advancements have demonstrated that LDH-based hybrids are suitable nanocomposites for photocatalytic applications when combining LDH with other semiconductors. This article summarizes the progress in the field of LDH-based ternary composites with emphasis on the removal of organic pollutants and heavy metal ions from aqueous media. Moreover, the applications and synthesis of LDH-based ternary composites, including corresponding examples, are discussed. In addition, the interaction mechanisms between photocatalysts and contaminants in water are comprehensively explained. Finally, the review provides insights into the challenges and prospects for the advancement of LDH-based photocatalysts.

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Adsorption of Phenol from Wastewater Using Calcined Magnesium-Zinc-Aluminium Layered Double Hydroxide Clay

Sustainability ◽

10.3390/su12104273 ◽

2020 ◽

Vol 12 (10) ◽

pp. 4273

Author(s):

Lehlogonolo Tabana ◽

Shepherd Tichapondwa ◽

Frederick Labuschagne ◽

Evans Chirwa

Keyword(s):

Layered Double Hydroxide ◽

Low Cost ◽

Freundlich Isotherm ◽

Treatment Temperature ◽

Bet Surface Area ◽

Maximum Adsorption Capacity ◽

Phenol Removal ◽

Order Kinetic ◽

Equilibrium Data ◽

Double Hydroxide

The presence of priority and emerging aromatic-based pollutants in water sources is of growing concern as they are not bioavailable and are present in reuse plant feed streams. These pollutants have known mutagenic and carcinogenic effects and must therefore be removed. Adsorption has been widely accepted as a suitable remediation technology due to its simplicity. Clay-based adsorbents have attracted significant attention due to their low cost, environmentally benign properties and regeneration potential. The present work focused on the thermal modification of a commercial Layered Double Hydroxide (LDH) clay and its subsequent effectiveness as an adsorbent in the removal of phenol from wastewater. Calcination of the neat clay resulted in the formation of metal oxides with varying phases and crystallinity depending on the treatment temperature. The BET surface area increased by 233% upon calcination at 500 °C. The highest phenol removal (85%) was observed in the clay calcined at 500 °C compared to 10% for the neat clay. Optimization studies revealed a maximum adsorption capacity of 12 mg/g at an adsorbent loading of 10 g/L at pH 7. Phenol adsorption was postulated to occur via a two-stage intercalation and surface adsorption mechanism. The equilibrium data were best fitted on the Freundlich isotherm model which describes heterogeneous adsorption. The adsorption kinetics followed a pseudo-second-order kinetic model with rate constants of 4.4 x 10−3 g/mg.h for the first 12h and 6.1 x 10−3 g/mg.h thereafter.

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Layered Double Hydroxide Nanomaterial as Highly Efficient Adsorbent and its Recycling after Removal of a Carcinogenic Tartrazine Dye from Wastewater

Biointerface Research in Applied Chemistry ◽

10.33263/briac126.77257740 ◽

2021 ◽

Vol 12 (6) ◽

pp. 7725-7740

Keyword(s):

Layered Double Hydroxide ◽

High Efficiency ◽

Low Cost ◽

Dye Adsorption ◽

Infrared Analysis ◽

Retention Capacity ◽

Before And After ◽

The Matrix ◽

Two Phases ◽

Double Hydroxide

In this work, the tartrazine dye is removed from the wastewater by the layered double hydroxide (LDH) [Zn2-Al-Cl]. LDH materials have proven to be highly effective in removing pollutants, with a low cost of synthesis, non-toxic, and they do not regenerate the sludge. Several parameters were studied, the retention of dye by LDH nanomaterial is optimized for a pH between 6 and 8, the equilibrium retention is obtained after 24 hours, and retention kinetics follows the pseudo-second-order model. The isotherms are the H type, and they follow the Langmuir model, retention capacity reaches 100% for a mass ratio (adsorbate/adsorbent) between 0.1 and 0.5, and the maximum amount retained of the dye is 740.35 mg/g for an initial concentration of tartrazine was 1200 mg/L and 100 mg of mass of LDH. X-ray diffraction (XRD) showed that the synthesized matrix is crystallized in a lamellar structure. Two processes affect the removal of the dye, adsorption of the surface of LDH, and intercalation between the layers. Infrared analysis indicated the appearance of the band's dye in the spectrum of the matrix after retention. Moreover, scanning electron microscopy showed the lamellar character of the two phases obtained before and after retention. The thermodynamics study showed that the process is endothermic, and the adsorption mechanism is governed by physisorption. The LDH nanomaterial is a good adsorbent with low cost, high efficiency, and recyclable.

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Research on the application of horseradish peroxidase and hydrogen peroxide to the oil removal of oily water

Water Science & Technology ◽

10.2166/wst.2009.177 ◽

2009 ◽

Vol 59 (9) ◽

pp. 1751-1758 ◽

Cited By ~ 6

Author(s):

Z. L. Li ◽

W. Liu ◽

X. F. Chen ◽

W. L. Shang

Keyword(s):

Hydrogen Peroxide ◽

Horseradish Peroxidase ◽

Low Cost ◽

Oily Wastewater ◽

Oil Removal ◽

Ion Temperature ◽

Effect Factors ◽

Oil Concentration ◽

Oily Water ◽

Application Prospects

Horseradish peroxidase (HRP) has the advantages of low cost, obtaining convenience, broad substrate specificity, etc, so it may be a suitable kind of enzyme to remove dilute emulsified oil and dissolved oil from water. The effect factors of the oil removal using HRP, such as pH, concentrations of HRP and H2O2, additives, Fe2 + ion, temperature and reaction time were researched. When the initial oil concentration was 120 mg/L, the remaining oil concentrations of the synthetic oily water and an actual oily wastewater reached 24.83 mg/L and 21.30 mg/L, respectively. The treatment of oily water using HRP and H2O2 is feasible. It has good application prospects.

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