Search results

1 – 10 of 178
To view the access options for this content please click here
Article
Publication date: 26 March 2021

Hamed Mahallei and Kazem Badv

The purpose of this paper is to assess sand-bentonite liners (SBL) which could be used as hydraulic barriers with a controllable quality, relatively low cost and easy…

Abstract

Purpose

The purpose of this paper is to assess sand-bentonite liners (SBL) which could be used as hydraulic barriers with a controllable quality, relatively low cost and easy operation in solid waste landfills.

Design/methodology/approach

These barriers have been used successfully in various applications and have attracted much attention in a short period of time. The only precautionary use of SBLs is related to the change of their hydraulic properties in high alkaline chemical environments. The main reason for this phenomenon is the presence of high ion exchange minerals in bentonite. By exposure to these environments, it is also laid open to degradation of the montmorillonite microstructure leads to change in hydraulic behavior. Three different compounds were used for laboratory-scale SBL, and diffusion was considered as the dominant mechanism of contamination transmission in these liners. Chlorine ion has been used as pollutant, and its diffusion coefficient was determined in the tested SBLs.

Findings

The sample’s diffusion coefficient for the first experiment containing 3% bentonite and 97% Semnan sand were 2.5 × 10^(−9) (m^2/s) and 2.44 × 10 ^(−9) (m^2/s), respectively. Similarly, for two samples with 6% bentonite and 94% Semnan sand, this parameter was equal to 2.17 × 10 ^(−9) (m^2/s) and 2.22 × 10 ^(−9) (m^2/s) and for two samples with 3% agglacial clay, 12% bentonite and 85% Semnan sand was 5.55 × 10 ^(−10) (m^2/s) and 6.11 × 10 ^(−10) (m^2/s). These values correspond to the range reported in previous studies. Also, it was observed that with comparing the diffusion coefficients of test, it was concluded that with increasing bentonite, the molecular diffusion decreases significantly.

Originality/value

In this study, three laboratory samples with different percentages of bentonite, clay and sand were considered and the results obtained from the laboratory were compared with the results obtained from numerical modeling.

Details

World Journal of Engineering, vol. 18 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

To view the access options for this content please click here
Article
Publication date: 20 October 2020

Lamiaa Kamal El-Gabry, Mohamed Fathy Nasr and Amira Adel Abou El-Kheir

This work aims to increase the dyeability of nylon 6 with basic dyeing through the treatment of the fibre with available and cheap nanomaterials, namely; nano bentonite

Abstract

Purpose

This work aims to increase the dyeability of nylon 6 with basic dyeing through the treatment of the fibre with available and cheap nanomaterials, namely; nano bentonite using an economic and simple method.

Design/methodology/approach

Different amounts of nano clay, namely, nano bentonite were dispersed in distilled water using an ultrasonic homogenizer for 1 h. Nylon fabrics were treated with different concentrations of dispersed nano bentonite (1%, 2%, 3%, 4%, 5% wt/v). After half an hour, the samples were padded using SVETEMA laboratory padding system. The padding pressure was adjusted at 3 bar to allow a pickup of 100%. The padded samples were dried at 80°C for 5 min and cured at 160°C for 3 min using ROACHES laboratory thermos-fixation. The cured samples were then washed with running water and left to dry at room temperature.

Findings

The obtained results indicated that the modification of polyamide 6 fibres with nano bentonite had a great impact on their dyeing properties. The obtained shades, absorption behaviour and fastness properties were significantly enhanced. Based on these results, it was concluded that polyamide fabrics could be successfully dyed with basic dyes using economical dyeing conditions.

Originality/value

This paper introduces a new method the loaded the nano-clay on the synthetic fibres, which are nylon 6 to enhance the dyeability with cationic dyes using the physical method without changing the structure of the fibres.

Details

Research Journal of Textile and Apparel, vol. 25 no. 1
Type: Research Article
ISSN: 1560-6074

Keywords

To view the access options for this content please click here
Article
Publication date: 17 May 2013

Nivin M. Ahmed, Hassan S. Emira and Hesham M. Tawfik

Ion‐exchange clays containing sodium such as bentonite and montmorillonite have the ability to exchange their cations. Few studies conducted with this type of ion‐exchange…

Abstract

Purpose

Ion‐exchange clays containing sodium such as bentonite and montmorillonite have the ability to exchange their cations. Few studies conducted with this type of ion‐exchange pigments are not conclusive about their anticorrosive efficiency. The present research aims to address the study on the anticorrosive efficiency of this type of pigments in chlorinated rubber paints. Sodium‐bentonite was exchanged with Zn, Sr and Zn‐Sr to be applied on low carbon steel specimens and study the anticorrosive performances of these new ion‐exchanged bentonites (IEBs) in anticorrosive paint formulations.

Design/methodology/approach

The new pigments were characterised using scanning electron microscopy (SEM) and X‐ray fluorescence (XRF) to determine the CEC (cation exchange capacity) of the different exchanged cations. Evaluation of the ion‐exchanged and Na‐bentonite pigments using international standard testing methods (ASTM) was estimated. Paint systems manufactured with these ion‐exchange pigments have been subjected to adhesion, accelerated corrosion laboratory tests, and EIS in order to assess their anticorrosive behaviour.

Findings

The results of this work revealed that the ion‐exchange bentonite (IEBs) pigments showed high anticorrosive performance that can be arranged as follows: Sr‐bentonite was better than Zn‐Bentonite and both were better than the double Zn‐Sr‐bentonite indicating an antagonism behaviour between the two cations when present together.

Practical implications

These pigments can be applied in other polymer composites, e.g. rubber and plastics as reinforcing agent and fillers.

Originality/value

These prepared pigments are environmentally friendly pigments which impart high anticorrosive behaviour to paint films with great economic savings.

Details

Pigment & Resin Technology, vol. 42 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

To view the access options for this content please click here
Article
Publication date: 3 June 2014

Tiedan Chen, Yanqiu Xia, Zhilu Liu and Zeyun Wang

The mixture of attapulgite and bentonite was used as a thickener, and polyalphaolefin was used as the base oil to prepare the new lubricating grease. Some solid particles…

Abstract

Purpose

The mixture of attapulgite and bentonite was used as a thickener, and polyalphaolefin was used as the base oil to prepare the new lubricating grease. Some solid particles such as Polytetrafluoroethene (PTFE), MoS2, nano-calcium carbonate and graphite were added in the new lubricating grease as anti-wear additives to investigate the tribological sensitivity.

Design/methodology/approach

The new lubricating grease was evaluated by optimol-SRV reciprocating friction and wear tester, and the wear volumes were determined using a MicroXAM-3D. At the same time, the dropping point and the cone penetration were investigated and analyzed. The tribological properties of the new lubricating grease and the sensitivity of some solid lubricating additives to the new lubricating base grease were investigated; pure organic-bentonite and pure organic-attapulgite base grease were used as contrast.

Findings

The new lubricating grease based on the surface-modified bentonite/attapulgite clay base grease was synthesized with a relatively high dropping point, and the mass ratio is 25/75 bentonite/attapulgite clay base grease, having a better tribological performance. MoS2 was used as an anti-wear additive that has good tribological sensitivity to the new lubricating base grease.

Originality/value

The main innovative thought of this work lies in the mixture of attapulgite and bentonite used as thickener. A relevant report is not available at present.

Details

Industrial Lubrication and Tribology, vol. 66 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

To view the access options for this content please click here
Article
Publication date: 5 May 2015

Salwa H El-Sabbagh, Doaa S. Mahmoud, M. F. Zawrah, Nivin M. Ahmed and Magdy W. Sabaa

The purpose of this paper is to evaluate the efficiency of organobentonite (OB) as reinforcing filler in acrylonitrile-butadiene rubber (NBR). The composites were prepared…

Abstract

Purpose

The purpose of this paper is to evaluate the efficiency of organobentonite (OB) as reinforcing filler in acrylonitrile-butadiene rubber (NBR). The composites were prepared using different loadings of OB and studying in details their properties. A series of OB was modified using surfactant N-cetyl-N, N, N-trimethyl ammonium bromide (CTAB) with concentrations 0.5, 1 and 2 cation exchange capacity (CEC) of bentonite.

Design/methodology/approach

The different bentonites were characterized using different analytical and spectro-photometric techniques, such as infra red, X-ray diffraction, thermogravimetric analysis and scanning electron microscopy, while rubber vulcanizate rheological, morphological, swelling and thermal properties were examined using different standard instrumental testing and methods.

Findings

The study revealed that the modification of bentonite using CTAB showed significant enhancement on NBR properties, and the optimum filler loading was 12 phr for both 0.5CEC OB and 2CEC OB. These modified bentonites improved reinforcing properties to NBR vulcanizates. Also, results showed that composites exhibited remarkable improvements in tensile strength, elongation at break and hardness in the presence of modified bentonite and also an increase in thermal stability.

Research limitations/implications

Na-B cannot be applied in rubber matrix without modification because it is incompatible with it.

Practical implications

The modified bentonite is considered as efficient reinforcing filler which can replace other fillers because it has lower surface energy and improved intercalating behaviour in rubber matrix.

Originality/value

These papered bentonites are cheap with relatively high purity, which make rubber/clay composites emerge as new class of material and can be used in different fields other than rubber.

To view the access options for this content please click here
Article
Publication date: 1 June 1990

Organophilic Sylodex Bentonites are organically treated forms of the clay mineral montmorillonite. The latter is present in the form of microscopically small platelets…

Abstract

Organophilic Sylodex Bentonites are organically treated forms of the clay mineral montmorillonite. The latter is present in the form of microscopically small platelets. The platelets are characteristic of the crystalline structure of the montmorillonite. The chemical composition is that of an aluminium hydrosilicate in which the silicon, aluminium and oxygen atoms are arranged in 3 layers (see Fig. 1). The outer layers consist of SiO2‐tetrahedra and the inner layers of (AlO4(OH)2) octahedra. An idealized initial structure of the precursor of montmorillonite exhibits the following neutral formula:

Details

Pigment & Resin Technology, vol. 19 no. 6
Type: Research Article
ISSN: 0369-9420

To view the access options for this content please click here
Article
Publication date: 11 January 2021

Oxana Ostakh, Elena Uzyakova, Natalya Grechishcheva and Violetta Kusheeva

The purpose of this study is to determine the possibilities to use drill cuttings in soil formation processes on sandy substrates. The ecological and toxicological…

Abstract

Purpose

The purpose of this study is to determine the possibilities to use drill cuttings in soil formation processes on sandy substrates. The ecological and toxicological assessment of drill cuttings of various genesis and mixtures based on them is applied for the purpose.

Design/methodology/approach

Acute toxicity of mixtures consisting of various drill cuttings, sand and peat was estimated using soft wheat seeds (Triticum aestivum) using the eluate method. Subacute toxicity experiments were carried out using creeping trefoil (white clover) seeds (Trifolium repens), rye seeds (Secale cereale), and garden radish seeds (Raphanus sativus L.). Drill cuttings of the West Siberian oil-and-gas basin generated as a result of drilling on clay-polymer drilling fluids can be used as a component of soil-like mixtures in the reclamation of sand fills. Patterns of the selective stimulation of seed growth by components of drilling fluids (xanthate and bentonite) were revealed.

Findings

It was found that the addition of bentonite and xanthan (0.05% by weight of the cuttings each) reduces the suppression of seed growth occasioned salt content by 21.1% and 24.0%, respectively.

Originality/value

Soil degradation and desertification is a serious and widespread problem. The restoration of the fertile layer can be launched by application of the artificial soil-like mixtures based on drill cuttings of a certain origin to the disturbed lands.

Details

Journal of Engineering, Design and Technology , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1726-0531

Keywords

To view the access options for this content please click here
Article
Publication date: 1 August 2003

Y. Ichikawa, K. Kawamura, N. Fujii and Theramast Nattavut

Materials commonly involve microstructure. Clay is a microinhomogeneous material with nanoscale microstructure. Key issues to understand the behavior of such a finely…

Abstract

Materials commonly involve microstructure. Clay is a microinhomogeneous material with nanoscale microstructure. Key issues to understand the behavior of such a finely microinhomogeneous material are as follows: the microstructure is characterized in detail, the local distribution of material properties is identified by experiment or simulation, and the microscale characteristics are related to the macroscale behavior by a seamless manner. For characterizing a microstructure of bentonite, we introduce a conforcal laser scanning microscope (CLSM) together with SEM. By CLSM we can specify a 3D configuration under atmospheric condition. Properties of water‐saturated bentonite are mainly controlled by hydrated montmorillonite, which is the major clay mineral of bentonite. Smectite minerals including montmorillonite are extremely fine and poorly crystallized, so it is difficult to determine the properties by experiment. We inquire into the physicochemical properties by a molecular dynamics simulation method. Then, we develop a multiscale homogenization method to extend the microscopic characteristics to the macroscopic behavior. We show numerical examples of a diffusion problem.

Details

Engineering Computations, vol. 20 no. 5/6
Type: Research Article
ISSN: 0264-4401

Keywords

To view the access options for this content please click here
Article
Publication date: 24 June 2020

Laylay Mustafa Alhallak, Seha Tirkes and Umit Tayfun

This study aims to investigate the mechanical, thermal, melt-flow and morphological behavior of acrylonitrile-butadiene-styrene (ABS)-based composites after bentonite

Abstract

Purpose

This study aims to investigate the mechanical, thermal, melt-flow and morphological behavior of acrylonitrile-butadiene-styrene (ABS)-based composites after bentonite inclusions. Melt mixing is the most preferred production method in industrial scale and basically it has very near processing parameters compared to 3D printing applications. Rheological parameters of ABS and its composites are important for 3D applications. Melt flow behavior of ABS effects the fabrication of 3D printed product at desired levels. Shear thinning and non-Newtonian viscosity characteristics of ABS make viscosity control easier and more flexible for several processing techniques including injection molding, compression molding and 3D printing.

Design/methodology/approach

ABS copolymer was reinforced with bentonite mineral (BNT) at four different loading ratios of 5%, 10%, 15% and 20%. ABS/BNT composites were fabricated by lab-scale micro-compounder followed by injection molding process. Mechanical, thermo-mechanical, thermal, melt-flow and morphological properties of composites were investigated by tensile, hardness and impact tests, dynamic mechanical analysis (DMA), thermo-gravimetric analysis (TGA), melt flow index (MFI) test and scanning electron microscopy (SEM), respectively.

Findings

Mechanical tests revealed that tensile strength, elongation and hardness of ABS were enhanced as BNT content increased. Glass transition temperature and storage modulus of ABS exhibited increasing trend with the additions of BNT. However, impact strength values dropped down with BNT inclusion. According to MFI test measurements, BNT incorporation displayed no significant change for MFI value of ABS. Homogeneous dispersion of BNT particles into ABS phase was deduced from SEM micrographs of composites. Loading ratio of 15% BNT was remarked as the most suitable candidate among fabricated ABS-based composites according to findings.

Research limitations/implications

The advanced mechanical properties and easy processing characteristics are the reasons for usage of ABS as an engineering plastic. Owing to the increase in its usage for 3D printing technology, the ABS became popular in recent years. The utilization of ABS in this technology is in filament form with various colors and dimensions. This is because of its proper rheological features.

Practical implications

Melt-mixing technique was used as preparation of composites, as this processing method is widely applied in industry. This method is also providing similar processing methodology with 3D printing technology.

Originality/value

According to the literature survey, to the best of the authors’ knowledge, this study is the first research work regarding the melt-flow performance of ABS-based composites to evaluate their 3D printing applications and processability. ABS and BNT containing composites were characterized by tensile, impact and shore hardness tests, DMA, TGA), MFI test and SEM techniques.

Details

Rapid Prototyping Journal, vol. 26 no. 7
Type: Research Article
ISSN: 1355-2546

Keywords

To view the access options for this content please click here
Article
Publication date: 29 July 2020

Zhang Fengjun, Kong Cui and Chen Qianbao

The purpose of this paper is to explore the factors that affect the compactness of the mud filter cake, so as to prepare diaphragm wall slurry with good uniformity, small…

Abstract

Purpose

The purpose of this paper is to explore the factors that affect the compactness of the mud filter cake, so as to prepare diaphragm wall slurry with good uniformity, small filtration loss and excellent recycling performance.

Design/methodology/approach

In this paper, the thickness, filtration loss and slurry viscosity of the filter cake are used as the characterization methods. The effects of pore depth, slurry specific gravity, intercalated metal ions, bridging polymer and water-soluble polymer on the compactness of the filter cake were studied.

Findings

The experimental results showed that the slurry's own pressure (pore depth) and specific gravity have little influence on the compactness of the filter cake and K+ can be considered as an auxiliary filtration loss reduction factor. Both the sulfonate copolymer and the potassium polyacrylate particle can significantly reduce the filtration loss of the slurry, which can effectively improve the filter cake compactness. Moreover, the composite application of potassium polyacrylate particles in the sizes of 80–100 and 150–200 meshes can exhibit a better filter cake compaction effect.

Originality/value

It solves the problems of high pulping cost, serious pollution of the environment, poor quality of filter cake formation and large filtration loss during the construction of the diaphragm wall, which improved the construction quality of the diaphragm wall.

Details

Pigment & Resin Technology, vol. 50 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

1 – 10 of 178