Engineering and Technology Journal

Bentonite is a mixture of clay and non-clay minerals. Montmorillonite clay mineral is a dominant mineral in bentonite. Silica and alumina bond in the crystal structure of montmorillonite. Therefore, they cannot contribute to the pozzolanic reaction. Heat treatment of bentonite leads to the destruction of the crystal structure of montmorillonite and converting silica and alumina to reactive phases. Thermally activated bentonite (TAB) is a relatively low reactive pozzolan when used as partial replacement of Portland cement modifies both fresh and hardened properties of cement paste, mortar, and concrete. The most desired effects of TAB are: improve segregation resistance, reduce the rate of strength gain, and enhance concrete durability against sulfates, chlorides, and acids, in addition to economic and ecological beneficiations. This paper provides information related to heat treatment of bentonite clays and montmorillonite minerals, and their effects on the paste, mortar, and concrete when used as a partial replacement of Portland cement.

Recently, the world has directed to find environmentally friendly and clean materials to be used to treat wastes difficult to treat in the traditional way such as dyes. The object of this study was to synthesize iron nanoparticles using black tea extracts in an environmentally sustainable method. Also, it was developed by supporting with bentonite, used to remove Eriochrome blue-black B dyes from synthesis wastewater of textile factory. From the results, it was noted that black tea leaf extract has reduced iron ions to iron nanoparticles at room temperature. Composite iron nanoparticles were characterized using Scanning Electron Microscope (SEM), and Atomic force microscopy (AFM) studies where the diameter of iron nanoparticles was less than 70 nm. This research shows that ferrous nanoparticles can be manufactured using black tea leaf extract as a reducing agent. It also shows better-supported nanoparticles than unsupported. The decolorization efficiency catalyzed BT-NZVI, B-BT-NZVI increased from (14%, 42%) to (48%, 68%) at 180 min of batch processes when the NZVI concentration was increased from 0.5 g/L to 2 g/L respectively.

The bentonite is an adsorbent material that is used frequently in industrial fields. bentonite was used with laser to treat wastewater, when laser is a new technique that has ability to remove the dye. Using of laser as a source to refresh with high efficiency has the important in industrial field.In this study laser diode with power 50 mw, He-Ne laser with power 10 mw and DPSSL with power 500 mw were used with the help of ultrasonic bath and H2O2 to promote the work of the laser. AFM and FTIR testing were made to bentonite to study the characteristics of it. Minitab program was used to facilitate calculations and choose the optimum parameters of experiments. The optimum input conditions of experiments to remove the dye from wastewater were chosen. The best concentration of bentonite is 4 g/l, the best temperature of wastewater is 42◦C, the best time of work is 27 min and the best concentration of H2O2 is 10%. It found from study that the increase of each parameters cause decrease in output concentration of wastewater. The accuracy of work was determined from Minitab program, it was 94.54%.

Corrosion processes are accountable for serious losses in the oil industry. Although organic and inorganic materials and mixed materials inhibitors have been used for a long time to control or reduce corrosion. Using nano-materials as inhibitors has gained an increasing applications role because of their exceptional properties. Nano materials are good corrosion inhibitors because they possess many advantages such as high efficiency of inhibition, low cost, minimum toxicity and effortless production. This work examines the use of nano-materials as inhibitors to prevent corrosion of carbon steel in drilling mud. Anti-corrosion properties of zinc and nickel ferrite nano materials (ZnFe2O4, Zn0.6Ni0.4Fe2O4) have been investigated over carbon steel in local Iraqi bentonite mud as a source of the corrosion. It has been found that under the given conditions, ferrites act as efficient corrosion inhibitors of carbon steel.

The present study investigated the possibility of enhancing collapsible gypseous soil of Al-Qarma site (with relatively high gypsum content around 50%), which is located in Al-Anbar Governorate, using kaolinite and bentonite as additives. The essential idea is concentrated in mixing these additives with natural soil using different percentages (5, 10, 15 and 20% by soil dry weight) to investigate soil shear strength enhancement. The effect of such additives on soil shear strength parameters, cohesion (C) and angle of internal friction (Φ), and their behavior were studied using direct shear test. The results showed that shear strength parameters of soil sometimes increased and then decreased with increasing additives. Generally, higher shear strength parameters have been obtained from bentonite mixed soil than that of kaolinite mixed soil for the same percentages of additives. It was concluded that bentonite was much more effective in increasing C and reducing Φ than kaolinite. While, kaolinite was much more effective in reducing C than bentonite. It was also concluded that gypseous soil shear strength is improved using such additives (with only 5% kaolinite or with only 20% bentonite) which provide cohesion strength to the soil mass and also acts as a binder agent material.

The sandy soil which covers the surface layer for the investigated area consists of
high gypsum content (50%). The soil was found to be a “collapsible” soil. Thus
bentonite and kaolinite have been used as an improving agents for such soil. The
essential idea of this study represents an investigation of the possibility of using
these materials as additives with different percents (5%, 10%, 15%, and 20%) to
enhance these soils. A testing program was conducted on 9 models of untreated and
treated gypseous soil specimens to study the behavior of such mixes as well as their
effects on physical properties, collapsibility and compressibility characteristics. It
was concluded that a significant reduction in collapsibility reaching 80 to 82 % for
the 10 percent mixed kaolinite and bentonite respectively. Lowest compression
index (Cc) and recompression index (Cr) have been obtained using the same
percentages of mixed additives. Generally, best improving results have been
obtained using bentonite additive (specially the ratio 10%) for its finer grains than
those of kaolinite.

Two types of Iraqi clays (Kaolin and Bentonite) were used in bonding process
with different weight percentage (5%, 10%, 15%, 20%, and 25%) and with
different particle size from clays and silicon carbide.
The specimens were formed by using low biaxial pressing and two types of
internal lubricants (sodium silicate and the carbon paste) to increase the
specimen's cohesion. These specimens were sintered at various temperatures of
(1100°C, 1200°C, 1300°C, and 1400°C).
Increasing of clay percentage leads to decreasing the porosity. But it leads to
increase mechanical properties (compressive strength, diametrical strength and
bending strength ). Also, the effect of particle size on all properties is studied
together with sintering temperature. All mechanical properties (when bonded SiC
with bentonite) are higher than kaolin bonded SiC.

In the present work a new type of composite material has been prepared
from mixing of polypropylene and polyamide 6 at constant ratio (80/20)] and
adding different weight percent (0, 5,10,15)% of both local bentonite and red
kaoline fillers respectively by using single screw extruder .Some of mechanical
properties such as tensile strength (Young modulus) tensile at fracture and
elongation of filled and unfilled PP/PN6 blends were determined at different
temperatures, and different weight percent of filler. Addition of filler increases the
Young modulus and tensile strength at break. Bentonite filler gives better
mechanical properties, than red kaoline fillers. Also empirical equations were
obtained which could be utilizing to calculate one of the mechanical properties in
term of temperatures and weight fraction of filler content. An equation was
proposed to show the best fit with experimental data, relevant contour diagrams,
for optimization of properties is also presented.

The present investigation is concerned to study the influence of poly vinyl
acetate (PVAc.) on flow behavior of bentonite dispersions in water, poly vinyl acetate
was added to the bentonite dispersion in different concentration (5, 7.5, 10, 12.5, 15, 17.5
and 20) gm/l. after that, the flow properties of these samples was measured and that
included (viscosity, shear stress, shear rate and Bingham yield value), The results show
thixotropy flow by a hysteresis loop of the flow curves for bentonite dispersion with and
without poly vinyl acetate, but with (PVAc.) give higher fluidity flow.
Also the morphology of bentonite dispersions was analyzed before and after adding
poly vinyl acetate by scanning electron micrograph (SEM), it is show that a weak
association between (PVAc.) and bentonite dispersions.