Showing papers in "Applied Clay Science in 1988"

TL;DR: The rheological behavior of dispersions of montmorillonite in water is highly pH-and salt-dependent as discussed by the authors, which is exemplified for 4% (wt/wt) dispersions from Wyoming and its homoionic sodium form in water, at different pH and at temperatures from 20°C to 60°C.

TL;DR: In this paper, the authors used china clay as an adsorbent for removal of fluoride from water at different concentrations, temperatures and pH, and investigated the kinetics of adsorption and isotherms at different temperatures for the present system.

TL;DR: In this paper, the gelling properties of four different sources of sepiolites were compared with a Na-montmorillonite from Wyoming, based on ease of gel preparation, gel viscosity and yield stress, and the modulus of rupture of slip cast bars made with kaolinite.

TL;DR: The feasibility and safety of a high-level nuclear waste repository in the Columbia River basalts was investigated by the Basalt Waste Isolation Project (BWP) in this paper, where a mixture of crushed basalt and sodium bentonite was used as packing material around individual waste containers.

TL;DR: In this paper, the dependence of the interaction of montmorillonite with a brown-coal humic acid on the pH and electrolyte concentration was examined, and the effects of these two factors were studied separately.

TL;DR: In this article, the degradation of Na2CO3-activated bentonites has been investigated by X-ray diffraction, chemical analysis and rheology measurements, and the evolution of the Na content during ageing is the most important parameter in accounting for the loss of its rheological properties.

TL;DR: In this paper, the authors studied the interaction of montmorillonite with hydralazine hydrochloride, a cardiovascular drug, considering the following aspects: (a) the maximum adsorption capacity; (b) the mechanism of intercalation; and (c) the “in vitro” desorption of the drug.

TL;DR: In this paper, the conversion of 2-propanol and ethanol over these materials were carried out in order to assess their catalytic properties, and both the dehydration and dehydrogenation products were observed in every case, indicating that these materials have both acidic and basic properties.

TL;DR: In this paper, structural changes that kaolinite underwent when leached with H2SO4 were studied through IR, XRD and electron microscopy, and the evolution of IR bands and XRD spectra were analyzed as a function of Al3+ extraction, similar behavior in the (001) plane integrated intensity and the IR absorbance of bands assigned to bonds in which Al 3+ takes plane was found.

TL;DR: In this paper, the relative viscosity increment (RVI) and sediment volume (SV) of three smectitic clays taken both from within and outside the slip surfaces in the Kamenose landslide was assessed in terms of the clay sol saturated with sodium and calcium.

TL;DR: In this paper, a double ternary Bingham model was proposed to explain the complex rheological behavior of a mixture of deflocculant and clay in the presence of viscous, elastic and plastic properties.

TL;DR: In this article, the authors investigated the cracking behavior of an allophanic material by sedimenting an aqueous suspension of the material onto a filter paper in a Buchner funnel, and allowing the filter pad to dry out at ambient humidity and temperature.

TL;DR: In this paper, the adsorption of NH4+ and Zn2+ by four Korean zeolite samples which contained clinoptilolite, mordenite or both was measured by adding solutions containing NH4+, Zn 2+, or both, each at a concentration ranging from 1 to 7 meq/l.

TL;DR: In this article, a detailed mineralogical examination of their natural soil or soil-like materials was performed and the smectite species was identified as ferriferous beidellite containing approximately 10% Fe 2 O 3.

TL;DR: Modified sepiolites, with aluminium, chromium or protons substituting octahedral magnesium, have been studied in this article, where the pyridine adsorption has been measured.

TL;DR: In this paper, the adaption of the herbicides Fluazifop-butyl and FluAzifop by two smectites homoionic to Al, Fe(III), Ca, Mg, Na, K and Cs, has been studied by infrared spectroscopy, X-ray diffraction and thin-layer chromatography.

TL;DR: Authigenic palygorskite is recorded only in the Esh-Shidiya area and Detrital kaolinite is an accessory clay mineral in the lower horizons of the Jordanian phosphates as mentioned in this paper.

TL;DR: Montmorillonite (Mont)/aliphatic amine complexes were synthesized using five kinds of C 2 -C 18 ) hydrochlorides, and their thermal degradation below 1473 K in nitrogen was examined as mentioned in this paper.

TL;DR: An extraction sequence in three steps with buffered hydroxylamine hydrochloride, oxalate and dithionite solutions was used for removal of Fe-oxide coatings from standard clay minerals: kaolinite, illite and mixed layer smectite/illite as mentioned in this paper.

TL;DR: In this paper, the influence of grain size distribution on the rheological behavior of Galician kaolins is studied, with favorable results, which allows them to be used in ceramic and paper industries.

TL;DR: In this paper, the authors measured the permeability coefficients during percolation of unconsolidated Triassic sandstone collected in drill cores in the Sherwood area (N.Ireland) and found that the effect of temperature on the evolution of permeability is different at different ionic strengths of the percolating solution.

TL;DR: In this article, the residues remaining after drying of visually clear colloidal sols from natural river water and artificially prepared suspensions of Source Clays were observed by scanning electron microscopy.

TL;DR: In this paper, the thermal stability of Li-taeniolite (TNL) and its complex with acriflavine (TAC) was studied under nitrogen. And the results gave directions for preparing a faultless clay-mineral/carbon-layer complex from clay/organic complexes.

TL;DR: In this article, a modified photometric method was developed to overcome the pitfalls of traditional photometric techniques, which fail to deliver circular vectorial data (both magnitude and direction) for preferred orientation, and cannot detect bimodal or polymodal patterns.

TL;DR: Halloysite was trimethylsilylated in a mixture of hexamethyldisiloxane, 2-propanol and hydrochloric acid to the extent that small amounts of raw halloysite remained.

TL;DR: In this paper, Na- and Ca-clays were flocculated from suspension by two anionic soluble polymers, and it was shown that the clay had to adsorb a minimum amount of polymer: 0.8 mg/g for a 0.735 g l−1 Na-montmorillonite suspension and 1.436 g l −1 Ca-montmorphite suspension.

TL;DR: In this article, the authors investigated the kind and stability of the main structural bonds between minerals and found that also other parameters are necessary to describe the geochemistry of the structural bonds in a better way.

TL;DR: In this paper, a triaxial swelling-pressure measuring device was used for the first time in assessing expansion stresses in the Pfaendertunnel in Vorarlberg, Austria.