Adsorption of Environmental Pollutants on Pillared Montmorillonite

Both inorganic and organic pillared montmorillonites were used to adsorb phenol. Batch kinetics and isotherm studies were carried out to evaluate the effect of equilibrium time and pH on adsorption of phe- nol by montmorillonites and re-adsorbing characteristics of pillared montmorillonites. The adsorption of phenol increased with increasing solution pH values. The elimination ratio of phenol from the solution by the absorption of organic modified pillared montmorillonite (OrPMt) reached equilibrium quickly after vibrating for 5 minutes. Meanwhile for organic montmorillonite (OrMt), pillared montmorillonite (PMt) and montmorillonite (Mt), the time to reach phenol-absorption equilibrium were 20, 30 and 90 minutes, respectively. The adsorbing capacity of the pillared montmorillonite modified with surfactant improved greatly. The phenol-adsorbing capacity of pillared molltmorillonites mainly depended on microporous structure and surface component of the modified clays. After calcination at 500 ℃, the pillar structure and the basal spacing (1.83 um) were still stable. So the pillared montmorillonite could be recycled, and it was a potential material for adsorbing environmental pollutants.

Dehalogenation of Aryl Halides Catalyzed by Montmorillonite Immobilized Bimetal Catalyst in Aqueous System

A novel bisupported bimetal catalyst PVP-PdCl2-FeSO4/Al-Mont-PEG600 was prepared by immobilization of PVP （poly （N-vinyl-2-pyrrolidone）） supported bimetallic catalyst using alumina pillared inartificial montmorillonite as the carrier. This catalyst has good dehalogenation activity and selectivity to aryl halides o-chlorotoluene in aqueous system in the presence of phase transfer catalyst （PEG） and sodium formate as hydrogen source. The catalyst also shows good reusability.

Hydrogenation of Benzene at Presence of Rhodium Support Catalyst

In this article, hydrogenation of benzene in liquid phase at presence rhodium support catalyst is considered, where as carrier is used pillar structural montmorillonite obtaining from bentonite clay. The degree of using an internal surface of porous system is depended of the size particles.

Facile Synthesis of Al-pillared Mesoporous Montmorillonite Assisted with Concentrated Al13 Solution

Al-pillared mesoporous montmorillonite was facilely synthesized from concentrated Al13 solution obtained by vacuum concentrating-ultrasonic pillaring strategy.Concentrated Al13 solution could reduce the process of pillare and increase pillaring efficiency.The absolute value of layer distance could be increased by 0.96 nm via concentrated Al13 solution pillare.27Al NMR indicates that Al Keggin ions of concentrated Al13 are arranged in a more regular way by vacuum concentrating method.The Al-pillared mesoporous montmorillonite from concentrated Al13 solution has bigger specific surface area and even pore size distribution which were characterized by X-ray diffraction（XRD） and nitrogen adsorption measurement.Furthermore the catalytic activity of Ai-pillared montmorillonite loaded Ni and Mo catalysts was tested by the hydrodesulfurization of thiophene.The thiophene conversion reached 77.5％,which was higher than the corresponding value reported in the literature.

Hierarchical MoS2 intercalated clay hybrid nanosheets with enhanced catalytic activity

Emerging hierarchical MoS2/pillared-montmorillonite （MoS2/PMMT） hybrid nanosheets were successfully prepared through facile in-situ hydrothermal synthesis of MoS2 within the interlayer of cetyltrimethylammonium bromide PMMT, and their catalytic performance was evaluated by the reduction reaction of 4-nitrophenol （4-NP） using NaBH4 as a reductant. Microstructure and morphology characterization indicated that MoS2/PMMT exhibited hybrid-stacked layered structures with an interlayer spacing of 1.29 nm, and the MoS2 nanosheets were intercalated within the montmorillonite （MMT） layers, with most of the edges exposed to the outside. The catalytic activity and stability of MoS2/PMMT were both enhanced by the MMT. With the MoS2/PMMT as the catalyst, the apparent reaction rate constant of the 4-NP reduction was 0.723 min-1 and was maintained at -0.679 min-1 after five reaction cycles. The structural evolution of MoSdPMMT and the possible catalysis mechanism for the reduction reaction of 4-NP were investigated. The as-prepared MOSR/PMMT hybrid nanosheets are promising candidates for catalytic application in the water-treatment and biomedical fields. The strategy developed in this study can provide insights for designing hybrid nanosheets with diverse heterogeneous two-dimensional （2D） nanomaterials.

Synthesis and Characterization of New Material --La/Zr/MMT Employed in Acetone Oxidation

A new material of zirconium pillared montmorillonite added with lanthanum （denoted as La/Zr/MMT） was prepared for acetone oxidation. Surface properties of the catalysts were investigated by means of XRD, TEM, TG-DTA and BET methods. The XRD result indicated that the interlayer space of the montmorillonite was enlarged from 1.57 to 4.85 um after the treatment with zirconium pillaring and the addition of lanthanum. N2 adsorption-desorption result showed that by the process of zirconium pillaring, the specific surface area of the sample was increased to 128.0 m^2/g, which was two times almost as large as pure montmorillonite. Simultaneously, the thermal stability was also enhanced. The activity of the new material on the total oxidation of acetone was investigated, and the results indicated that the catalytic activity of the montmorillonite was greatly improved. Over the sample of La/Zr/MMT, the T98 of acetone was obtained at 350 ℃, while it needs 400 ℃ over the pure montmorillonite. After 0.1% Pd was supported on the sample of La/Zr/MMT, the T98 decreased from 350 to 280 ℃, indicating the montmorillonite is a promising material for the control of some types of the volatile organic compounds such as acetone.

Enhanced gelled hydrocarbon well treatment fluids

Compared with water-based well treatment fluid systems,hydrocarbon-based fluids possess advantages such as better fluid compatibility and lower formation damage,especially in water-sensitive formations.Hydrocarbonbased fluids are therefore often used in oilfield operations including hydraulic fracturing,sand control,and coiled tubing cleanout.The metal-crosslinked,phosphate ester-based gelled hydrocarbon(or gelled oil)fluids have been the preferred choice among hydrocarbon-based fluids since they are cost effective,robust at elevated temperatures,and operationally simple as only a couple of fluid additives are involved.Functioning as the gelling agent in gelled oil fluids,phosphate ester could cause fouling in refinery equipment.It is therefore desirable to lower the dosage of the phosphate ester-based gelling agent as much as possible,but without adversely affecting the fluid performance.A number of materials have been identified that could enhance the gelled oil viscosity and stability,which in turn translates into the reduction of the phosphate ester needed in the gelled oil.Among these enhancing materials,a type of aluminum pillared montmorillonite clay(the additive)was found to enhance the gelled oil viscosity to the largest extent.In laboratory tests,30 ppt(30 pounds per thousand gallons)of the additive increased the gelled oil viscosity by 84%(±5%)at 250°F when compared with the baseline gelled oil without the additive.With the additive dosage at 30 ppt,the amount of the phosphate ester in the gelled oil could be reduced by 25%without decreasing the fluid viscosity.The additive was successfully applied to the crude oil-based gelled fluid,resulting in multiple times of viscosity increase in the study.In addition to the gelled oil viscosity enhancement,the additive also increased the regained permeability in the coreflow tests to near 3 times.