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Exploitation of Nigerian bentonitic clay deposit will offer economic advantage in terms of utilization for drilling purpose and prevent money spent on importation. Clay used for this analysis was beneficiated using sodium Carbonate (Na2CO3) and the change in the elemental composition of the raw clay sample and treated clay with was estimated using X-ray fluorescence spectroscopy (XRF). The treated clay and locally sourced bio-materials were added to the formulation of drilling fluid using Reduced Central Composite Design (RCCD). The fluid loss and cake thickness of prepared drilling fluid were determined using filter loss test kit. The result of the investigation show that the maximum recorded fluid loss was 14.4 ml/30mins at 100 psi while cake thickness values improved with addition of the bio-materials to the drilling fluid formulation when compared with the standard values.

It is about problems in purification of industrial wastewater and utilization of solid wastes as raw materials resources which are needed a scientific way of studying. The way of generation composite granular sorbent filter material on the basis of man-caused and minerals, using which is allowed to increase ecological safety food industry enterprise because of using waste conversion technique, as well modern methods of sorption purification , is offered and described here. A detailed chemical composition, which consists of tobacco dust and natural component as bentonitic clay, using for getting granular sorbent filter material, is studied. They studied real industrial wastewater to make researches for the detection residual impurity in the filtrate using composite granular sorbent filter material.

Bentonitic clay is an important material required during drilling operation in oil and water industry. This study seeks to assess the deposit of the Bentonitic clay characteristics using geophysical techniques and geochemical assessment of the bentonitic clay unit in Afuze. Vertical Electrical Sounding (VES) using Schlumberger electrode arrangement were carried out along six traverses to determine the subsurface lithological characteristics of the area. Representative samples of the bentonitic clay layers were collected for X-Ray fluorescence (XRF) analyses and free swelling index parameters. The geophysical results show an appreciable thickness of the bentonitic clay unit among other stratigraphic units and are well defined based on its resistivity characteristic. The geochemical results show that the clay is a Ca-rich bentonitic type with a relatively low swelling properties and distinct to the Wyoming bentonite type. The Afuze bentonitic clay will be suitable for industrial application as drilling additives if beneficiated to increase the Na content in the clay and enhance its rheological properties for effective use in drilling operations.

The interaction between bentonitic clays and exchangeable cations Na+, К+, Ca++, and Mg++ is studied theoretically. It is stated that the insertion of exchangeable cations into the interlaminar space leads to reducing of the interlayer distance as compared with that calculated for the undoped clay. At that, the clay particles having Mg++ on their surface demonstrate more stable structure upon the increase of moistening. The calculation results for Mg++ compare well with the experiment performed.

The local consumption and the high importation cost of imported bentonite to Egypt led to find local substitute solutions for economical aspects. Hence, this paper presents the composition and activation capability of clays collected from the claystone quarries in Kom Oshim area at El-Fayoum province, Egypt for their application as a drilling fluid (water-based mud). It is an attempt to minimize the importation cost of the imported bentonites to Egypt by a local solution and maximize the usage of the studied clay sediments. The physical, chemical, thermal and mineralogical characteristics of five Egyptian clay samples were studied. The rheological properties of the prepared slurries from these samples and their activation characterization during studying the influence of NaOH and POLYPAC-R polymer as activators were investigated. It was found that the non-activated samples cannot be used as a drilling mud but it could be after the activation process where some significant changes in the rheological properties were observed. The experimental results revealed that the activated fitted samples may express as medium grade bentonitic clay and this type of clay can be used as a drilling fluid for shallow depth wells.

The purpose of the present investigation was to apply a discriminant function analysis (DFA) to quantitative mineralogical data from 124 Paleogene and Neogene bentonitic clays from the northern Western Desert of Egypt in order to establish an objective procedure for grouping the samples at three distinctly recognizable, but partially overlapping, levels of classification. These levels were province or geographic region, geologic age, and quarry. Quantitative mineralogical data were obtained by means of X-ray diffraction procedures employing least-squares fitting of simulated and standard mineral patterns with those from the laboratory. All data were transformed by a log-ratio procedure prior to the DFA. Fe-rich smectite (Feoct-1.4 a.p.f.u.), coarsely crystalline kaolinite, Fe-poor I-S (random with 60% S layers), quartz, and illite were the most important discriminator minerals. S-moderate I-S (random with 70% S), S-rich I-S (random with 80% S), two varieties of finely crystalline kaolinite, feldspar, and amorphous matter were also present. Calcite and gypsum were present in some samples. The median wt.% values for Fe-rich smectite, coarsely crystalline kaolinite, Fe-poor I-S, quartz, and illite in all samples were 16.6, 16.0, 15.2, 4.2, and 3.7, respectively. Abundances of quartz and feldspar have a good positive correlation, and finely crystalline kaolinite and Fe-rich smectite are negatively correlated. Other specific mineral associations are difficult to interpret visually because of the numbers of classes and variables employed in the investigation; however, DFA was successful in identifying statistically significant differences amongst the groups. At the province level, the back-classification of the samples was successful 92% of the time at the highest probability level, or 100% if the first plus second probability results were utilized. For samples of the same age, 80% of the first-choice assignments were correct and >90% were correct when the second choice was included. At the quarry level, the predictability rate ranged from 76 to >90%. Using both probability results, only seven of the samples were misclassified. In a blind test of quarry samples, the DFA assignment was 80% correct. These tests confirm the objective reliability of class assignments based on DFA. Results based on this data set can be used to classify new samples in future geologic interpretations and economic exploitation of the deposits in the region.

Miocene siltstone with variable sand content and bentonitic clay is the most abundant sediments encountered at the metro construction site at Rakoczi Square (Budapest). Core logs, drilling reports and records of laboratory analyses were studied to better understand the local geology and to prepare a database on engineering geologic properties of the materials. Using this database, geologic sections were prepared and geomathematical methods were used to obtain a better correlation of the strata in the area and a reconstruction of the geologic evolution of the area. The samples were divided into five groups based on physical properties. These five parameters allowed the use of multivariate statistical methods as cluster and discriminant analysis. As a result it was possible to identify several types of lithotypes, including two bentonitic clays with substantially different properties, one fat clay, one medium clay and one sandy, lean clay and siltstone group.

A pre–late Pliocene mega-landslide was discovered in southwest San Diego County during grading of several residential subdivisions. Outcrop evidence indicates that a single lateral spread occurring on a single continuous, bentonitic clay bed and encompassing approximately 125 km 2 occurred between 1.5 and 28 Ma. Steeply dipping shears separating lateral spread blocks mimic the structure in the nearby La Nacion fault zone. Future studies of faults in areas suspected to be within the lateral spread will need to differentiate tectonic faulting from lateral spread deformation. Investigations should include deep borings to determine if bentonite clay beds exhibit evidence of vertical offsets as a result of normal faulting. In addition to a well-developed basal rupture surface, the lateral spread debris contains discontinuous and unpredictably-oriented internal shears and fractures within large blocks of debris that will affect slope stability. Because much of the structure cannot be evaluated completely by subsurface investigations, in-grading mapping and engineering analysis are necessary to provide appropriate recommendations for stabilization of site-specific slopes.

Nigeria is ranked the seventh largest exporter of crude oil in the world. On a daily basis, it produces over two million barrels of crude Oil from hundreds of Oil wells drilled in the Niger Delta area. Not a single of these Oil wells are drilled without the use of Bentonite. Bentonite is a clay powder that is mixed with water (drilling mud) and forced through a drilling string into the wellbore during drilling operations in order to float and lift drilled cuttings out of the well, control the down-hole temperature, lubricate drilling bit, prevent corrosion and stabilize the wall of the hole from collapsing among other things. A very large sum of money is being spent by the Oil companies operating in Nigeria on the importation of millions of tons of Bentonite from overseas for Oil well drilling. Nigeria has large reserve of Bentonitic clay deposit that if properly utilized will go a long way in supporting the Oil well drilling demand in the country. This will translate into retaining the large sum of money sent overseas for importation of foreign Bentonite, create employment opportunities, bring external investment and boost the country’s economy. Though the Bentonite deposits studied are Ca-based, it can be beneficiated to a level that is comparable with the standard compliance. This study has beneficiated local Bentonitic clay using Na 2CO 3 as the beneficiating agent and ion exchange as the procedure. The rheological properties of the beneficiated clay were determined together

This paper presents the results of a series of experiments conducted to examine the hygro-thermal behaviour of a compacted, internally heated engineered clay barrier, consisting of a mixture of bentonitic clay and sand, compacted in a laboratory scale model simulating a waste emplacement borehole located in a granitic rock. The experiments considered the supply of water at a prescribed pressure at the outer cylindrical and plane boundaries of the compacted, engineered clay barrier. The experiments examined the manner in which the water supply conditions influenced the extent of the moisture uptake within the compacted clay barrier. The experimental results presented in this paper include contours of the time-dependent variation of temperature within the granite block, the time-dependent variations of temperature at the midsection level of the internally placed heater and along the axis of the experimental facility, and the residual volumetric moisture content distribution determined at the termination of the experiments.

A one-pot general alternative to prepare dithioacetals, with excellent yields, via the condensation of 1,3-propanedithiol, benzyl, and n-butyl mercapthanes with several carbonylic compounds using a bentonitic earth as the catalyst is proposed. Also, the acidic role of the clay in the reaction is discussed. The product structures were established by 1H and 13C NMR, as well as by the corresponding EIMS and HRMS data. To the memory of Professor Alvaro Leo Ramirez.

Supported MnO2 or HNO3 on bentonitic clay cleanly oxidize some hydroquinones under infrared or microwave irradiation to the corresponding quinones with excellent conversion in short reaction times, using an easy and solvent-free approach.

The authors have investigated the equilibrated adsorption of water vapors on GFG hopcalite, which was obtained using the extrusion shaping method, with bentonite clay as the binding compound. In the frames of the BET model, the values of the monolayer capacity and the size of medium area occupied by the water molecule in the filled monolayer have been determined. The distribution of pores according to their sizes has been evaluated. It has been established that the modification of the bentonitic clay allows directed construction of the hopcalite porous structure,i.e. the formation of the mesoporous structure with a narrow distribution of the pores capacities by sizes, which was achieved varying the sizes of binding compound particles.

Instrumental neutron activation analysis was applied to the determination of trace elements in a Na-bentonitic clay. The irradiation was done in the Triga Mark II type reactor of ITU Nuclear Energy Institute. The sample was irradiated in two steps for “short-” and “long-” lived isotopes. After irradiation, spectra were taken using a germanium detector, multichannel analyzer Canberra System 100 and a fitting program called Sampo 90. The spectra of short-lived isotopes were analyzed to determine Al, Mg, Na, K, Ca, Ti elements and Mn, V trace elements. The spectra of long-lived isotopes were analyzed to determine Sc, Br, Sb, Cs, La, Ce, Sm, Yb, Hf, Pa, Np trace elements.

The paper presents the results of a series laboratory experiments which were conducted to study the heat-induced moisture movement in a bentonitic clay buffer region. In the experimental investigations, hygro-thermal phenomena are induced by a cylindrical heater which is placed within the compacted buffer material located in a borehole centrally situated in a granite block. The paper summarizes the experimental methodologies and presents results for the time-dependent distribution of temperatures within the granite block and the residual moisture distribution within the buffer at the termination of the experiment.

International audience; Thermophysical characterization is a useful tool for studying mixtures of clay and saline solutions and evaluating their suitability from a thermotherapic point of view. This work focuses on studying the specific heat capacity, density, thermal conductivity and viscosity of a bentonitic clay (composed mainly of 55% Na+-saturated trioctahedral smectite, 28% sepiolite and 15% illite) mixed with different saline solutions (0, 1, 2, 3 and 3.5%) in the temperature range 293.15 to 317.15K. The results indicate meaningful differences in the thermal behavior of the studied pastes in relation to thermotherapy and pelotherapy.

An oxidative deblocking procedure of ketoximes using bentonitic clay supported silver carbonate, is proposed. Reaction yields are competitive with those methods previously reported, easy of set-up and work-up was encountered, some important characteristics of the clay are reported.

The flocculating efficiency of two cationic polyelectrolytes with quaternary ammonium salt groups in the main chain, with different branching degrees, on a bentonitic clay suspension, in comparison with polyacrylamide (PAM) was followed. The cationic polymer with a smaller branching degree operated similar to PAM. In both cases a purification of 100% was achieved. When the cationic polymer with a higher branching degree was used, a stabilization effect on the suspension was observed. The flocculating activity of the mixtures of the cationic polymer and polyacrylamide was also studied. Die Flockenbildungswirksamkeit von zwei kationischen Polyelektrolyten mit quaternaren Ammoniumsalzen in der Kette und verschiedene Verzweigungsgraden wurde an einer Bentonit-Suspension untersucht und mit der von Polyacrylamid verglichen. Das kationische Polymere mit einem kleineren Verzweigungsgrad wirkt ahnlich wie Polyacrylamid und fuhrt zu einer Entfernung von 100% der Suspensionspartikel. Im Fall des kationischen Polymeren mit einem hoheren Verzweigungsgrad wird eine Erhohung der Stabilitat der Suspension bei sehr kleinen Konzentrationen (>0,2 mg/L) beobachtet. In gleicher Weise wurde die Flockenbildungswirksamkeit fur kationische Polymer/Polyacrylamid-Mischungen studiert.

International audience; In thermotherapy, an appropriate and detailed chemical and physical characterization of the different clays and thermal muds is necessary for the use of these products. In order to predict the thermal behaviour of a mud the analysis of its physical properties is required; among these, those that have bigger influence are the specific heat capacity, the thermal conductivity and the density. This work focuses on the study of the behaviour of the specific heat of a bentonitic clay (composed mainly of 55% Na-saturated smectite, 28% sepiolite, and 15% illite) mixed with distilled water or sea water as a function of the water concentration in the temperature range 293.15-317.15 K. The experimental data were measured using a Calvet calorimeter, SETARAM BT 2.15, which permits studying with high precision all kind of substances and materials (oils, polymers, hydrates, powders) and simulate almost any process condition (reactions, crystallisation, freezing, etc.). The obtained specific heat values in the studied temperature range are between 851 and 889 J kg -1 K -1 for mineral phase, 3479 and 3505 J kg -1 K -1 for 19.9% bentonite + distilled water, and 2724 and 2758 J kg -1 K -1 for 39.8% bentonite + sea water. The results of this study can be used in the spas or thermal centres to determine the suitability and quality of the bentonitic muds for pelotherapy.

Tonsil Actisil FF, a commercial bentonitic clay, promotes the formation of a series of electrophilic-aromatic-substitution products from para-methoxybenzyl acetate in carbon disulfide. The molecules obtained correspond to linear isomeric dimers, trimers, tetramers and a pentamer, according to their spectroscopic data. A clear indication of the title mechanistic pathway for the oligomerization growth was obtained from the analysis of a set of computational-chemistry calculations using the density-functional-theory level B3LYP/6-311++G(d,p). The corresponding conclusions were based on the computed dipole moments, the HOMO/LUMO distributions, and a natural-populations analysis of the studied molecules.

An oxidative deblocking procedure of ketoximes using bentonitic clay supported silver carbonate, is proposed. Reaction yields are competitive with those methods previously reported, easy of set-up and work-up was encountered, some important characteristics of the clay are reported.

(1995). OXIDATIVE CLEAVAGE OF KETOXIMES WITH BENTONITIC CLAY-SUPPORTED COPPER (II) NITRATE. Organic Preparations and Procedures International: Vol. 27, No. 4, pp. 480-482.

Research on the longevity of potential bentonite-based barrier materials is an important part of the Canadian Nuclear Fuel Waste Management Program. Valuable information on the longterm effectiveness of bentonitic barriers can be obtained by examining the properties of unprocessed bentonites from natural deposits. This study compares the swelling capacity (Ps) and hydraulic conductivity (K) of an unprocessed (clay that has not been ground and dried by the supplier) and a processed bentonite from south-central Saskatchewan, Canada. The clay deposit is 75 to 85 Ma old. At a given clay density, the processed bentonite exhibits a greater P3 and a lower K than the unprocessed clay. This can be at least partially attributed to the partial cementation of the unprocessed bentonite particles; this cementation is likely ruptured when the clay is ground during processing. Even though K for the unprocessed clay is higher than that of the processed clay, it is still low enough (

In this paper, the dielectric spectra of moist bentonitic clay in the range of frequencies from 0.2 GHz to 15 GHz and temperatures from -30degC to +25degC have been obtained. Based on these results, a dielectric model of frozen clay soil was proposed which allows for predicting complex dielectric permittivity as a function of frequency and temperature.

The reaction of a number of aldehydes and ketones with 1,3-propanedithiol has been carried out in the absence of solvent, using microwave irradiation as the heat source. Under these conditions the corresponding 1,3-dithianes were obtained in short reaction times (5 min). In addition, a bentonitic clay was evaluated as promoter of this reaction

(1995). OXIDATIVE CLEAVAGE OF KETOXIMES WITH BENTONITIC CLAY-SUPPORTED COPPER (II) NITRATE. Organic Preparations and Procedures International: Vol. 27, No. 4, pp. 480-482.

The reaction of a set of five aldehydes, ethyl acetoacetate and urea or thiourea (Biginelli reaction) has been performed over a bentonitic clay as the catalyst, under solventless conditions using infrared irradiation as the energy source, obtaining the corresponding dihydropyrimidones .

Supported MnO2 or HNO3 on bentonitic clay cleanly oxidize some hydroquinones under infrared or microwave irradiation to the corresponding quinones with excellent conversion in short reaction times, using an easy and solvent-free approach.