Fuller's Earth Research Articles

Stabilization of swelling clays by Mg(OH) 2. Changes in clay properties after addition of Mg-hydroxide

Stabilization of the swelling clay structure is attempted by intercalation of Mg(OH) 2 and the development of a brucite interlayer between the clay layers. The properties of the product obtained by applying the technique, formulated as described in a previous work, are considered here. The materials used were Wyoming bentonite (USA), Fuller's Earth (UK), kaolinite, illite, lignite, and silica gels. The Mg(OH) 2-clay products were examined by the methylene blue dye test, X-ray diffraction analysis (XRD), differential thermal analysis (DTA), and derivative thermogravimetry analysis (DTGA). From the results obtained it is concluded that: the Mg-hydroxide is adsorbed by swelling clays both on their external and internal surface, whereas it is adsorbed on the external surface by non-swelling clays. The internally adsorbed phase of Mg-hydroxide forms an ill-defined interlayer of brucite, retarding swelling, whereas the external phase covers the particles modifying drastically their surface properties, like the adsorption of the MB dye. The material produced after precipitation of Mg-hydroxide on swelling clays (smectites) did not re-expand on wetting or after glycolation. The adsorption of MB dye was also reduced by some 80–90%, due to coating effect, preventing the measurements of the external surface area of the clay by polar molecules. The principal forces involved in the process are believed to be physical adsorption on the external surface, along with chemisorption and some chemical bonding, mostly in the internal surface. Cementation due to crystallization and, in the long term, some pozzolanic reactions take also place. Internal adsorption of the Mg-hydroxide is postulated to be in the form of positively charged mono- and/or small polymers and it is, chiefly, diffusion controlled. Since Mg-hydroxide is internally adsorbed by swelling clays, whereas Ca-hydroxide(lime) is not, and the (Mg, Ca)-clay aggregates are more stable than the Ca-clay or the Mg-one, the combination of the two hydroxides could give better results in soil stabilization than each hydroxide alone.

Effects of Fuller's Earth and activated charcoal on oral absorption of paraquat in rabbits.

1. Thirty male rabbits of local strain (weighing 1.5-2 kg) were divided into five groups. Four groups were treated with an oral dose of paraquat, which was followed by either Fuller's Earth or activated charcoal 0.5 or 2.0 h later. The remaining group acted as the control group and was treated only with an oral dose of paraquat. The dose of paraquat was 20.0 mg/kg given in a concentration of 20.0 mg/mL. 2. Both adsorbents were administered in 15 mL normal saline as a 30% slurry. Blood was sampled from the ear vein 0.5, 1, 2, 4, 8 and 24h after the administration of paraquat. 3. Paraquat concentration was determined spectophotometrically at 600 nm by comparing against a standard curve of paraquat obtained by the addition of standard paraquat into normal rabbit serum and extracting interfering substances with ether. 4. The results of the present study show that either adsorbent can bring down the serum paraquat level. There was no significant difference found in the effectiveness of either adsorbent. 5. It is concluded that the administration of an adsorbent as early as possible will help in the reduction of paraquat absorption from the gastrointestinal tract. 6. Activated charcoal is still effective in lowering serum paraquat concentration when given more than 1 h after ingestion of paraquat.

Tem and X-Ray Diffraction Evidence for Cristobalite and Tridymite Stacking Sequences in Opal

AbstractIn an attempt to resolve the structure of opal-CT and opal-C more precisely, 24 opal samples from bentonites, Fuller's Earths, zeolite tuffs, biogenic silicas and silicified kaolins have been analyzed by high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). Results of this examination demonstrate that opal-C and opal-CT are part of a continuous series of intergrowths between end-member cristobalite and tridymite stacking sequences.These findings are consistent with Flörke's (1955) interpretation of the most intense opal peak at ~4 Å as a combination of the (101) cristobalite and (404) tridymite peaks. The position and width of this peak are controlled by the relative volume of the two stacking types and the mean crystallite size. Direct evidence obtained by HRTEM provides data showing various stacking sequences in opals. Broadening due to crystallite size alone was determined by directly measuring crystallite size by TEM and comparing the measured size to the apparent size calculated using the Scherrer equation. XRD peak broadening is also described in terms of various contributions from structural disorder. The mean opal crystallite size ranges from 120 to 320 Å. For samples at either end of the size range, the crystallite size plays a larger role, relative to stacking disorder, in controlling peak broadening.

The sedimentological significance of concentrically laminated burrows from Lower Cretaceous Ca-bentonites, Oxfordshire

Concentrically laminated burrows are common at outcrop and in core in Mesozoic and younger shallow marine siliciclastic sedimentary rocks. They are generally referred to Cylindrichnus concentricus Howard. an imperfectly understood ichnotaxon here considered to be a nomen dubium. Concentric lamination can be formed in several ways: either actively contrived by the producer, or by passive filling (draught filling) of a burrow with constricted apertures. In the latter case the fill cannot be regarded as an ichnotaxobase. Passive infilling of concentrically laminated, bow-form, deep-tier burrows is described from Lower Cretaceous (Aptian) sedimentary rocks associated with fuller's earth (Ca-bentonite) at Baulking, Oxfordshire. The distribution and taphonomy provide information on the sedimentological setting of the tephra and associated sediments. The lower seam was already compacted and of clay grade before it was repeatedly eroded and colonized the latter has significantly reduced seam quality. Subsequent sedimentation was essentially aggradational, including the uniquely preserved upper bentonite which had a complex recovery history. Among other ichnotaxa, concentrically laminated Thalassinoides (and possibly Diplocraterion ) may be misidentified as ‘Cylindrichnus’. Since Thalassinoides and Diplocraterion are important indicators of bounding surfaces, information of significance in sequence stratigraphy may be lost as a consequence. Citations of Cylindrichnus in the literature are briefly discussed: many must be assigned to other ichnotaxa.

Effects of some additives on the performance of acid-activated clays in the bleaching of palm oil

The effects of FeCl 3 and CUS0 4 on the performance of acid-activated clays in bleaching of palm of oil have been examined. Activation of the clay by an acid strength of 15% proved most effective. The effects of the additives on the performance of these acid-activated clays depend on the type and amount of the additive. For both salts added the maximum performance was obtained when the additive content is 12%. The ferric salt was more effective in improving the performance of the acid-activated clay than the Cu 2+ salts. The performance of the activated clay with 12% Fe 2+ salt as additive compares favourably with that of the commercial adsorbent, Fullers Earth.

Interview with Richard Oelman

Richard Oelman is the Senior Laboratory technician at Coulsdon College. Richard started work at Fullers Earth in Redhill and has been a technician in a number of schools. He has trained as a teacher, and joined the staff at Coulsdon College in 1991.

Evaluation of a 2-active ingredient gas cartridge for controlling northern pocket gophers

The efficacy of a four-ingredient (two active and two inert) gas cartridge to control northern pocket gophers in an oat-alfalfa hay field was evaluated. The reformulated rodent gas cartridge was jointly developed by the Denver Wildlife Research Center and Pocatello Supply Depot to replace the currently registered eitht-ingredient gas cartridge. The reformulated cartridge contains sodium nitrate and charcoal as active ingredients, with Fuller's earth and borax as inert ingredients. When ignited, the active ingredients produce primarily carbon monoxide. Four test areas (one control and three fumigated) were randomly established with 15 sample plots (each 0·008 ha) on each test area. Active burrow systems were treated: (1) in the sample plots; (2) outside the sample plots but within each test area; and (3) in the buffer zone around each test area. Pocket gopher activity on each plot was determined pre- and post-testing by an open-hole index. Although there was an increase in pocket gopher activity on the control test area and declines of 7·1, 13·3 and 30·8% on the three test areas receiving the gas cartridges, the difference in activity was not statistically different ( p = 0·174). The 17·1% mean reduction in pocket gopher activity in the fumigated test areas was substantially below the minimum standard efficacy of 70% established by the U.S. Environmental Protection Agency for fumigants. This result was similar to two previous studies conducted with the original eitht-ingredient gas cartridge for the control of northern pocket gophers.

The role of mineral processing in reducing the environmental impact of mining activity in Cornwall, UK

The causes of environmental impact from mineral extraction are discussed. The problems associated with contaminated land in general and some of the previous reclamation techniques are reviewed. Mineral processing techniques and novel approaches to reclamation, developed at Camborne School of Mines (CSM), are described. The theoretical properties of various industrial minerals, their ability as in situ additions, or amendments, on contaminated land are presented. Mechanisms are described to explain the beneficial effects of such materials as kieselguhr, Fuller's earth, and certain zeolites, in treating contaminated land. Field trials of these and other materials are outlined. The relationship of these field trials to detailed laboratory tests is discussed. Possible uses as “end-of-pipe” additions for cleaner technology in minerals processing are outlined.

The influence of granular calcareous particles on the residual shear strength of Fuller's Earth clay : A. B. Hawkins, & C. McDonald, Quarterly Journal of Engineering Geology, 26(4), 1993, pp 321–325

The influence of granular calcareous particles on the residual shear strength of Fuller's Earth clay : A. B. Hawkins, & C. McDonald, Quarterly Journal of Engineering Geology, 26(4), 1993, pp 321–325

Distinguishing well ordered opal-CT and opal-C from high temperature cristobalite by x-ray diffraction

A critical step in quantifying the amount of crystalline silica in mineral deposits is the accurate identification of all mineral constituents. It is particularly important to correctly identify the low-temperature opaline silica polymorphs opal-C and opal-CT which, depending on degree of ordering, can be mistaken for α-cristobalite in standard x-ray diffraction patterns. Misidentification occurs because there is limited x-ray diffraction data available from the literature and because these minerals have diffraction maxima that coincide with those of high temperature cristobalite, X-ray diffraction patterns of opal have been collected in 20 bentonite, fuller's earth, and diatomaceous earth deposits to illustrate the range in ordering that naturally occurs in these polymorphs. Two opaline silica polymorphs are commonly observed. Opal-C is characterized by sharp, intense (101) reflections centered near 4.0 Å with peak widths ranging from 0.222 to 0.453 Å and opal-CT is characterized by broader, less intense (101) reflections centered near 4.07 to 4.10 Å with peak widths ranging from 0.506 to 0.883 Å. Opal-A was observed in one sample. Opal-A is easily distinguished from the other opaline silica polymorphs and from α-cristobalite using x-ray diffraction. Opal-C and opal-CT, however, are not as readily distinguished from α-cristobalite. The position and width of the (101) peak can be used to distinguish these polymorphs from one another or a simple heating test can be used. Because opaline silica is hydrated, the position of the (101) reflection shifts and sharpens as a result of heating When α-cristobalite is heated to change in peak position is observed. It has also been found that opaline silica, when reacted with phosphoric acid, potassium pyrosulfate, and sodium sulfide solutions, is considerably more chemically reactive than the crystalline silica minerals. Based on results of the heating test and the position and width of the 4 Å peak of the unheated sample, none of the 20 bentonite, fuller's earths, or diatomaceous earth deposits analyzed contain high temperature α-cristobalite.

A step forward in enzymatic measurement of creatinine

We describe an improved enzymatic ultraviolet absorbance method for assaying creatinine in serum, plasma, and urine. Creatinine is hydrolyzed by creatinine iminohydrolase (EC 3.5.4.21) to ammonia and N-methylhydantoin. The ammonia produced combines with 2-oxoglutarate and NADPH in the presence of glutamate dehydrogenase to yield glutamate and NADP+. The consumption of NADPH, measured by a two-point fixed-time assay, is proportional to the amount of creatinine in the sample. The assay is carried out in two steps: The first step eliminates background absorbance in hyperlipemic samples and endogenous ammonia through a "clearing system" and an isocitrate dehydrogenase-based "ammonia scavenger system"; the second step starts creatinine measurement. The method affords a simple, rapid, and sensitive assay with good precision and extended linearity; it employs working solutions stable at least 4 months. Test results compare closely with those of the isotope dilution-mass spectrometry Definitive Method, the HPLC procedure, and the fuller's earth method. The proposed method is not subject to interference from several metabolites or from the 72 drugs tested. Because it is easily automated, the method is suitable for routine work in clinical laboratories.

Creatinine assay by the fuller's earth procedure or by enzymatic determination is adequate for urine but not plasma of mice

1. 1. Mouse plasma creatinine measured by fuller's earth (15.1 ± 0.5(41) μM, mean ± SE) exceeded the same pools read by HPLC [7.5 ± 0.2(41); P < 0.001]. 2. 2. For mouse urine, the fuller's earth method (3.26 ± 0.21 mM) slightly exceeded the HPLC method (2.65 ± 0.18; P < 0.001) with good correlation ( r = 0.915, P < 0.001). 3. 3. An enzymatic method (creatinine PAP, Boehringer-Mannheim Diagnostics) for plasma creatinine (5.2 ± 0.3 μM) was equivalent to HPLC (6.1 ± 0.1, NS) but with poor correlation ( r = 0.23, NS). 4. 4. Creatinine in the urine agreed closely between HPLC (2.84 ± 0.12 mM) and the enzymatic procedure (2.95 ± 0.17, NS) with good correlation ( r = 0.845, P < 0.001).

The influence of granular calcareous particles on the residual shear strength of Fuller's Earth Clay

Abstract Decalcification is proposed as a cause of the continued movement observed in many natural and engineered slopes in calcareous mudrock formations. It is deemed that such movement may potentially occur as granular calcareous particles, which otherwise maintain high residual shear strengths, are leached from shear surfaces within slipped masses, changing the mode of residual shear from transitional to sliding. Measurements of the residual shear strengths of 42 natural samples taken through the Fuller's Earth succession near Bath over a range of effective normal stresses emphasize the curved nature of many failure envelopes. The results demonstrate that the threshold between the two modes of shear occurs at approximately 25% calcite content. Fuller's Earth Clay with more than 25% calcite content is thus prone to significant decreases in residual shear strength upon partial or total decalcification.

Industrial Mineral Microscopy

Abstract What is industrial mineral microscopy? It is the application of any micro-analytical technique used to characterize and identify non-metallic and non-fuel earth materials. Humans have used industrial minerals since ancient times. The earliest known scientific work which dealt expressly with minerals and artificial products derived from them is Theophrastus On Stones. Theophrastus, a pupil and friend of Aristotle, described the use of fuller's earth and gypsum for whitening discolored cloth garments in the latter half of the 4th century, B.C. Fuller's earth is still used today as a decolorizing agent by manufacturers of oil and fat products. Gypsum, of course, is widely used in plaster of paris, cement, and paper. Today, industrial minerals are encountered often by people in everyday life. Electronic, pharmaceutical, cosmetic, construction, paper, and plastics industries use industrial minerals in a multitude of products.

Weathering and regolith properties at an earthflow site

Abstract The influence of weathering on the physical, chemical and geotechnical characteristics of soils has been examined for both unstable and adjacent stable ground at a site in North Island New Zealand where earthflows have developed in regolith overlying Tertiary calcareous mudrock of marine origin. The same sequence of weathering zones was visually identified during sample extrusion for both the unstable and stable ground, although the earthflow sites were characterized by extension of weathering to greater depths. Both the characteristics of the weathering zones and the relationships between calcite content and geotechnical index properties show significant similarities to those reported for the Fuller's Earth in the UK. Variations in density and moisture content throughout the profiles are attributed to variations in the extent of stress relief fissuring, augmented by a calcite content which varies with depth and position on the slope. If the variation in dry density (and moisture content) due to calcite content alone is removed, the depth at which stress relief fissuring becomes prominent can be readily discerned and appears to be associated with the zone of basal shear in the earthflows. Physico-chemical swelling appears to be absent, even though the soil mineralogy is dominated by Casmectites. Post-failure weathering, clay mineral alteration and calcite removal are expected to provide a mechanism for promoting gradually increasing earthflow instability.

Decalcification and residual shear strength reduction in Fuller's earth clay : Hawkins, A B; McDonald, C GeotechniqueV42, N3, Sept 1992, P453–464

Decalcification and residual shear strength reduction in Fuller's earth clay : Hawkins, A B; McDonald, C GeotechniqueV42, N3, Sept 1992, P453–464

APPLICATION OF NATURAL AND SYNTHETIC FULLER'S EARTH TO THE FRACTIONATION OF BITUMEN

ABSTRACT Synthetic (100% ) mentmorillonite and natural ( chlorite/ montmorillomite/palygorskite [33.3/36./30.5]) and Fullers earth have been used to fractionate bitumen. Insoite of the difference in the chemical composition and structure of the synthetic and natural Fuller's earth, their adsorption ability after activation are almost identical. Natural Fuller's earth was less selective in the soxhlet extraction compared to synthetic Fuller's earth. Pmr study of all fractions isolated indicate that HAB petrolenes have a high proportion of paraffinic and aromatic hydrocarbons and can be a good petrochemical feedstock. Fractions obtained from natural Fuller's earth are comparable to that isolated before using Attapulgus clay to fractionato Qaiyarah erude oil.

Decalcification and residual shear strength reduction in Fuller's Earth Clay

Analyses of borehole samples at 1 m intervals through the Fuller's Earth succession at Bath reveal an inverse correlation between calcite content and Atterberg limits. The calcareous component of the soil is shown to have a major influence on the ultimate residual shear angle with a threshold of 28% calcite content dividing the soils that behave solely in the sliding mode of shear from the remaining soils that shear predominantly in the transitional mode. The threshold can alternatively be defined at 40% Ip. Progressive laboratory décalcification of one sample with 36% calcite content resulted in an increase in liquid limit from 63% to 101% and in plastic limit from 21% to 33%, whereas the percentage clay fraction increased from 52% to 82%, emphasizing the influence of the silt grade calcareous particles. Decalcification is accompanied by a marked reduction in residual shear strength over a range of effective normal stresses, demonstrating the influence of medium and coarse silt grade particles. The distinct relationship between the calcite content and the geotechnical properties is particularly important as the calcite content is prone to change as a consequence of dissolution. L'analyse des échantillons pris tous les I m dans des sondages traversant les couches de sols de Fuller à Bath a montré une corrélation inverse entre la teneur en calcite et les limites d'Atterberg. On montre que la fraction calcaire du sol a une grande influence sur l'angle de cisaillement résiduel avec un seuil de 28% de teneur en calcite séparant les sols qui se comportent uniquement dans le mode de cisaillement par glissement des autres sols qui se cisaillent principalement dans le mode transitoire. Le seuil peut être également défini à 40% de Ip. La décalcification progressive en laboratoire d'un échantillon contenant 36% de calcite a entruiné un accroissement de la limite de liquidité de 63% à 101% et de la limite de plasticité de 21% à 33%; la teneur en argile s'accrut de 52% à 82% soulignant l'influence des particules calcaires de taille limoneuse. La décalcification s'accompagne d'une réduction marquée de la résistance au cisaillement résiduel pour des variations des contraintes effectives normales, démontrant l'influence des particules de taille limoneuses moyennes et grosses. La relation claire entre la teneur en calcite et les propriétés géotechniques est particulièrement importante car la teneur en calcite est sujette à des changements en raison des phénomènes de dissolution.

New early Barstovian (middle Miocene) vertebrates from the upper Torreya Formation, eastern Florida panhandle

ABSTRACT A new vertebrate fauna has been recovered from the Dogtown Member of the Torreya Formation, Hawthorn Group (early to middle Miocene), northern Gadsden County, Florida. Fossils were recovered from four fuller's earth clay mines. This new fauna, called the Willacoochee Creek Fauna (WCF), contains at least 68 vertebrate taxa, including 29 mammals, from marine, freshwater, and terrestrial environments. The WCF is restricted to the early Barstovian land-mammal age based on the presence of Copemys, Perognathus, Rakomeryx, and Ticholeptus, and the overlapping chronologic ranges of 8 other mammals. Lanthanotherium, Perognathus, and a squalodont whale are reported from the southeastern U.S. for the first time. Biochronological range extensions into the early Barstovian are proposed for Lanthanotherium, Anchitherium clarencei and “Merychippus” primus. The WCF is the first well documented early Barstovian fauna in the southeastern U.S., thus filling a large gap in the temporal distribution of vertebrate fau...

The Palaeogene vegetation of peninsular India (Megafossil evidences)

The Palaeogene represents the age of spread and diversification of angiosperms in the Indian sub-continent. A comprehensive knowledge of the Palaeogene flora of peninsular India is, therefore, necessary to decipher the history of the modern flora of India. The Palaeogene plant megafossils of this region can broadly be considered under (i) Deccan Intertrappean flora, (ii) Eocene flora of Kutch, (iii) Eocene plant fossils described from the Fuller's earth deposits near Barmer in Rajasthan, and (iv) Eocene plant records from Meghalaya.&#x0D; The flora as a whole is characteristically tropical in character. It consists of taxa belonging to marine, estuarine, freshwater, and terrestrial habitat with both evergreen and deciduous forms. It is suggestive of an equable warm and moist tropical climate over the whole of peninsular India during the Palaeogene. The existence of this type of climate was the result of (i) a more or less equatorial position of peninsular India during the Palaeocene-Eocene period, and (ii) a warm sea which not only surrounded the peninsula from all the sides but also intruded into the landmass.&#x0D; Most of the plants recovered from the Palaeogene localities of peninsular India still continue to grow in various forests of this region. Part of this flora, thus, can be considered to be the ancestral stock for the present-day flora of India. Occurrence of some African, Madagascarian, Australian and South American elements in this flora suggests India's past connections with these Gondwanaland countries.