Hybrid organic–inorganic derivatives of layered double hydroxides and dodecylbenzenesulfonate: Preparation and adsorption characteristics

Abstract

Layered double hydroxides (LDHs) are anionic clays that can be synthesized under laboratory conditions. In this study, different LDHs were synthesized by a coprecipitation method, with the parent products and calcined derivatives evaluated for their ability to adsorb the anionic surfactant, dodecylbenzenesulfonate (DBS). Adsorption isotherms for DBS retention on LDHs were typical L-type curves, with adsorption data conforming to a simple Langmuir equation. Langmuir maximum adsorption of DBS on calcined-LDH was significantly higher than that on uncalcined-LDHs. Organo-LDHs were also synthesized by incorporating DBS into LDHs via ion-exchange, reconstruction of calcined-LDH and in-situ synthesis methods. X-ray diffraction analysis of organo-LDHs revealed that DBS was intercalated into LDHs with the mono-layer DBS molecules oriented perpendicularly to LDH surfaces. Intercalation of DBS into LDHs decreased surface area according to BET analysis. The adsorption capacities of organo-LDHs for trichloroethylene (TCE) and tetrachloroethylene (PCE) were substantially greater than the original LDH materials. Adsorption of organic compounds by organo-LDHs was due to a partitioning mechanism.Reagent grade metal salts were obtained from Spectrum Quality Products (Gardena, CA, USA). Sodium dodecylbenzenesulfonate and the organic compounds, trichloroethylene

Inorganic nanolayers: structure, preparation, and biomedical applications

“…[58][59][60][61] Also, halogen anions and perchlorate anions have been removed by LDH application. [62][63][64][65] Organic 32,[67][68][69][70] In water-treatment plants, disinfection is an important procedure, and currently halogens and ozone are employed as disinfectants. However, there are certain issues with respect to these disinfectants, such as the fact that they can form genotoxic and carcinogenic by-products in the presence of organic compounds.…”

“…2,18 This is a very useful method, especially for the intercalation of organic molecules, and many different anions have been successfully incorporated in LDHs, such as caprolactam, organic chromospheres, dyes, surfactants, and metal complex anions, and this is even a very useful method for the intercalation of nonionized species, eg, sugar molecules like pentoses. [29][30][31][32][33] The whole process of rehydration should be carried out under an inert nitrogen atmosphere.…”

Compósitos de Poliestireno e Argila Aniônica Funcionalizada com Cinamato com Propriedade de Absorção de UV

“…O processo de obtenção de nanocompósitos envolve o estabelecimento da compatibilidade entre a carga inorgânica, de natureza hidrofílica e a matriz polimérica. No caso de utilizar um polímero hidrofóbico, como o poliestireno (PS), a modificação química da superfície dos LDH pela ação de agentes químicos contendo grupamentos orgânicos aniônicos pode reduzir as forças repulsivas e aumentar a compatibilidade da argila com o polímero, promovendo a dispersão e a intercalação das cadeias poliméricas, podendo até mesmo resultar em delaminação [8][9][10][11] . Alguns ânions orgânicos tais como, carboxilatos, sulfatos e sulfonatos, podem ser facilmente intercalados [11,12] .…”

Applications of Layered Double Hydroxides in Removing Oxyanions From Oil Refining and Coal Mining Wastewater

“…Most of these sorbents possess negatively charged surfaces; therefore fail to adsorb negatively charged oxyanions and cyanides. Organic substances can be intercalated with LDH (You et al, 2002) and cations, such as sodium, may also be removed by combining LDH with lignin, where lignin provides an anionic surface. Reverse osmosis (RO), which uses nano-membranes as the filters, is a highly effective tool to eliminate all impurities from water; however, the high cost of this technology prohibits its use in industrial wastewater treatment.…”