Evaluation of the Protection Ability of a Magnesium Hydroxide Coating against the Bio-Corrosion of Concrete Sewer Pipes, by Using Short and Long Duration Accelerated Acid Spraying Tests

The Microbiologically Induced Corrosion (MIC) of concrete sewer pipes is a commonly known problem that can lead to the destruction of the system, creating multiple public health issues and the need for costly repair investments. The present study focuses on the development of a magnesium hydroxide coating, with optimized properties to protect concrete against MIC. The anti-corrosion properties of the respective coating were evaluated by using short and long duration accelerated sulfuric acid spraying tests. The coating presented satisfying adhesion ability, based on pull-off and Scanning Electron Microscopy (SEM) analysis measurements. The surface pH of the coated concrete was maintained at the alkaline region (i.e., >8.0) throughout the duration of all acid spraying tests. The consumption of the coating, due to the reaction (neutralization) with sulfuric acid, was confirmed by the respective mass and thickness measurements. The protection ability of this coating was also evaluated by recording the formation of gypsum (i.e., the main corrosion product of concrete) during the performed tests, by X-ray Diffraction (XRD) analysis and by the Attenuated Total Reflectance (ATR) measurements. Finally, a long duration acid spraying test was additionally used to evaluate the behavior of the coating, simulating better the conditions existing in a real sewer pipe, and the obtained results showed that this coating is capable of offering prolonged protection to the concrete substrate.

Download Full-text

Comparison of Different Magnesium Hydroxide Coatings Applied on Concrete Substrates (Sewer Pipes) for Protection against Bio-Corrosion

Water ◽

10.3390/w13091227 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1227

Author(s):

Domna Merachtsaki ◽

Eirini-Chrysanthi Tsardaka ◽

Eleftherios K. Anastasiou ◽

Haris Yiannoulakis ◽

Anastasios Zouboulis

Keyword(s):

Sulfuric Acid ◽

Magnesium Hydroxide ◽

Concrete Surface ◽

Sem Analysis ◽

Acid Attack ◽

Sewer Pipes ◽

Surface Ph ◽

Adhesion Ability ◽

Coating Mass ◽

Surface Morphologies

Several coatings and linings have been examined and used for the protection of sewer concrete pipes, against mainly biogenic-provoked corrosion due to the production of bio-sulfuric acid, leading to the degradation of the pipes’ structure and eventually, to their collapse and need for costly replacement. This study aimed to examine the potential differences between five different magnesium hydroxide coatings, prepared from powders presenting different purity, surface area and pore size distribution, when applied as corrosion protection agents. These coatings were tested by using accelerated sulfuric acid spraying tests, both in dry and wet coating conditions. The coating adhesion ability and their microstructure were examined by the application of pull-off measurements and of SEM analysis, respectively and were found to present certain differences, regarding the adhesion ability and the surface morphologies. During the acid spraying procedure, the surface pH and the mass change of coated concrete specimens were recorded daily. The surface pH was reduced towards acidic values and the mass reduction approached almost −20% in comparison with the initial coating mass for certain cases. Additionally, the hardness and roughness of concrete surface under the coating layer (i.e., the interface between the coating and the surface) after four days of acid spraying, exhibited much smaller changes (due to protection) in contrast to the uncoated concrete specimens (used as blank/comparison experiments), which were found to be highly affected/corroded. The formation of concrete corrosion and coating by-products, as noticed after the respective chemical reactions, was recorded by X-ray diffraction (XRD) measurements and the respective quantification of obtained results. In all the coated specimens only very small amounts of the major by-product (gypsum) was observed, indicating that the concrete surface was sufficiently protected from sulfuric acid attack.

Download Full-text

Study of Corrosion Protection of Concrete in Sewage Systems with Magnesium Hydroxide Coatings

Environmental Sciences Proceedings ◽

10.3390/environsciproc2020002027 ◽

2020 ◽

Vol 2 (1) ◽

pp. 27 ◽

Cited By ~ 1

Author(s):

Domna Merachtsaki ◽

Eirini-Chrysanthi Tsardaka ◽

Evangelia Tsampali ◽

Konstantinos Simeonidis ◽

Eleftherios Anastasiou ◽

...

Keyword(s):

Sulfuric Acid ◽

Corrosion Protection ◽

Magnesium Hydroxide ◽

Low Cost ◽

Methyl Cellulose ◽

X Ray Diffraction ◽

Sewer Pipes ◽

Surface Ph ◽

Time Period ◽

Concrete Blocks

The purpose of the present work was to study the corrosion protection that relatively low-cost magnesium hydroxide coatings offer to concrete by stabilizing the surface pH. To facilitate the material’s adhesive ability, methyl-cellulose and carboxymethyl-cellulose were used as environmentally friendly additives in three different concentrations, 1, 0.4 and 0.1 wt.% of solids, respectively. The coatings were applied on the surface of concrete blocks, in two different coating thicknesses. A sulfuric acid solution was used to simulate the biologically produced acid in sewer pipes. Sulfuric acid was sprayed on the specimens, while the total amount of acid sprayed was calculated, in order to correspond to a specific reaction’s stoichiometry daily. The surface pH of coated specimens was monitored daily with a surface pH meter. The gypsum production was studied with X-ray diffraction, to evaluate the coatings’ protection. The experimental time period that coatings were consumed was compared with the theoretically consumption time.

Download Full-text

Development of Ternary Concrete Utilizing Agricultural Waste Material

10.21203/rs.3.rs-1107515/v1 ◽

2022 ◽

Author(s):

Sunita Kumari ◽

Dhirendra Singhal ◽

Rinku Walia ◽

Ajay Rathee

Keyword(s):

Rice Husk ◽

Rice Husk Ash ◽

Agricultural Waste ◽

Xrd Analysis ◽

Sem Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Concrete Mix ◽

Maize Cob

Abstract The present project proposes to utilize rice husk and maize cob husk ash in the cement to mitigate the adverse impact of cement on environment and to enhance the disposal of waste in a sustainable manner. Ternary concrete / MR concrete was prepared by using rise husk and maize cob ash with cement. For the present project, five concrete mixes MR-0 (Control mix), MR-1 (Rice husk ash 10% and MR-2.5%), MR-2 (Rice husk ash 10% and MR-5%), MR-3 (Rice husk ash 10% and MR-2.5%), MR-4 (Rice husk ash 10% and MR-2.5%) were prepared. M35 concrete mix was designed as per IS 10262:2009 for low slump values 0-25mm. The purpose is to find the optimum replacement level of cement in M35 grade ternary concrete for I – Shaped paver blocks.In order to study the effects of these additions, micro-structural and structural properties test of concretes have been conducted. The crystalline properties of control mix and modified concrete are analyzed by Fourier Transform Infrared Spectroscope (FTIR), Scanning Electron Microscopy (SEM), and X-Ray Diffraction (XRD). The results indicated that 10% Rice husk ash and 5% maize cob ash replaced with cement produce a desirable quality of ternary concrete mix having good compressive strength. The results of SEM analysis indicated that the morphology of both concrete were different, showing porous structure at 7 days age and become unsymmetrical with the addition of ashes. After 28 day age, the control mix contained more quantity of ettringite and became denser than ternary concrete. XRD analysis revealed the presence of portlandite in large quantity in controlled mix concrete while MR concrete had the partially hydrated particle of alite.

Download Full-text

Effect of Re and Tm-site on morphology structure and optical band gap of ReTmO3 (Re: La, Ce, Nd, Gd, Dy, Y and Tm: Fe, Cr) prepared by sol-gel method

Revista Mexicana de Física ◽

10.31349/revmexfis.64.381 ◽

2018 ◽

Vol 64 (4) ◽

pp. 381

Author(s):

Muhammad Tufiq Jamil ◽

Javed Ahmad ◽

Syed Hamad Bukhari ◽

Murtaza Saleem

Keyword(s):

Band Gap ◽

Sol Gel ◽

Xrd Analysis ◽

Sem Analysis ◽

X Ray Diffraction ◽

Orthorhombic Crystal ◽

X Ray ◽

Average Grain Size ◽

Auto Combustion ◽

Uv Visible

Rare earth nano sized pollycrystalline orthoferrites and orthocromites ReT mO3 (Re = La, Nd, Gd, Dy, Y and T m = Fe, Cr) have been synthesized by sol-gel auto combustion citrate method. The samples have been characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), and UV-visible spectroscopy. The samples are single phase as confirmed by XRD analysis and correspond to the orthorhombic crystal symmetry with space group pbnm. Debye Scherer formula and Williamson Hall analysis have been used to calculate the average grain size which is consistent with that of determined from SEM analysis and varied between 25-75 nm. The elemental compositions of all samples have been checked by EDX analysis. Different crystallographic parameters are calculated with strong structural correlation among Re and Tm sites. The optical energy band gap has been calculated by using Tauc relation estimated to be in the range of 1.77 - 1.87 eV and 2.77 - 3.14 eV, for ReFeO3 and ReCrO3, respectively.

Download Full-text

Hierarchical Nanostructured ZnO-CuO Nanocomposite and its Photocatalytic Activity

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.35.21 ◽

2015 ◽

Vol 35 ◽

pp. 21-26 ◽

Cited By ~ 16

Author(s):

Susmita Das ◽

Vimal Chandra Srivastava

Keyword(s):

Photocatalytic Activity ◽

Pure Copper ◽

Ultra Violet ◽

Xrd Analysis ◽

Sem Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Ultra Violet Radiation ◽

One Step ◽

Uv Visible

Metal oxide nanocomposite (ZnO-CuO) was successfully synthesized by one step homogeneous coprecipitation method and further characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron micrograph (SEM), X-ray diffraction analysis (XRD) and UV-visible diffuse reflectance spectra. XRD analysis exhibited presence of pure copper oxide and zinc oxide within the nanocomposite. SEM analysis indicated that the ZnO-CuO nanocomposite was consisted of flower shaped ZnO along with leaf shaped CuO. Photocatalytic activity of nanocomposite was evaluated in terms of degradation of methylene blue (MB) dye solution under ultra-violet radiation. Results showed that the photocatalytic efficiency of ZnO-CuO nanocomposite was higher than its individual pure oxides (ZnO or CuO).

Download Full-text

Synthesis, Structural Analysis of Cadmium Sulphide Nanocrystallites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.969.169 ◽

2019 ◽

Vol 969 ◽

pp. 169-174

Author(s):

R. Sivanand ◽

S. Chellammal ◽

S. Manivannan

Keyword(s):

Size Variation ◽

Cadmium Sulphide ◽

Xrd Analysis ◽

Sem Analysis ◽

Precipitation Method ◽

Capping Agent ◽

Energy Dispersive Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Scanning Electron

In this paper, the effect of size variation of cadmium sulphide nanocrystallites which have been prepared by precipitation method is analyzed. These prepared samples were studied using X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Energy dispersive analysis of spectroscopy (EDAX) techniques. SEM analysis represents the morphological nature of prepared samples and EDAX indicates the confirmation of elements present in the sample. XRD analysis determines the size of the samples and identifies the structure using miller indices (h k l values) of the nanocrystallies matches with JCPDS. From the XRD analysis, the size variation which depends on dopant, capping agent are discussed and corresponding results are reported in this paper.

Download Full-text

Preparation and Properties Study on the Composites of Polypropylene and Polyphenylene Sulfide Filled by Modified Molybdenum Disulfide

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.87-88.345 ◽

2009 ◽

Vol 87-88 ◽

pp. 345-350

Author(s):

Jian Qiang Zhang ◽

Hui Xia Feng ◽

Jian Hui Qiu

Keyword(s):

Surface Modification ◽

Molybdenum Disulfide ◽

Xrd Analysis ◽

Sem Analysis ◽

Polyphenylene Sulfide ◽

X Ray Diffraction ◽

Infrared Spectrometer ◽

Ft Ir ◽

The Fourier Transform ◽

Wear Modes

The wet surface modification process were used in this work to get the well lipophilic molybdenum disulfide (MoS2) powders and the modified MoS2 were filled into the polyphenylene sulfide (PPS) and polypropylene (PP) powders with different proportions to make polymeric based composites through hot-press molding equipment. The Fourier transform infrared spectrometer (FT-IR) analysis showed that the modification agents of stearic acid (SA), orγ-Methacryloxypropyl trimethoxy silane(KH570 or A-174), could react with the adsorption hydroxyl(−OH) of the MoS2 powders and finally form chemical coatings, the SA could form a layer of physics wrap too. The powder X-ray diffraction (XRD) analysis reveled that the SA or KH570 could not change the laminated structure of MoS2. The wearability testing showed that the composites filled by modified MoS2 owned the better wearable performances than the filled not one. From minimum to maximum, the wear mass rates of SA/MoS2/PP/PPS, KH570/MoS2/PP/PPS, PP/PPS were 0.7216, 5.4187 and 7.3198 percent in turns. Scanning electronic microscope (SEM) analysis showed the surface modification could uniformize the modified MoS2 to disperse in the polymeric based composites, and also reflect the abrasion mechanism which the particles and the adhering wear modes could all make the mass loss of the testing samples and they coexisted and could transform each other, the former would produce higher loss rates than the later and their leader status would gradually change from the particles wear to the adhering wear during the course of wearing-resisting tests.

Download Full-text

Corrosion properties of Zn-Ni-P alloys in neutral model medium

Open Chemistry ◽

10.2478/s11532-014-0564-9 ◽

2014 ◽

Vol 12 (11) ◽

pp. 1183-1193 ◽

Cited By ~ 5

Author(s):

Vassil Bachvarov ◽

Miglena Peshova ◽

Stefana Vitkova ◽

Nikolai Boshkov

Keyword(s):

Corrosion Resistance ◽

Xrd Analysis ◽

Ternary Alloys ◽

X Ray Diffraction ◽

Model Medium ◽

Experimental Conditions ◽

Corrosion Properties ◽

X Ray ◽

Protective Ability ◽

Corrosion Medium

AbstractThe presented work reports on the peculiarities of the anodic behavior, corrosion resistance and protective ability of electrodeposited Zn-Ni-P alloys with a different composition in a model corrosion medium of 5% NaCl. Three characteristic coating types have been investigated using experimental methods such as potentiodynamic polarization (PD) technique and polarization resistance (Rp) measurements. In addition, X-ray diffraction (XRD) analysis as well as scanning electron microscopy (SEM) coupled with an Energy-dispersive X-ray (EDAX) device were applied to determine the differences in the chemical composition and surface morphology which appeared as a result of the corrosion treatment. The data obtained are compared to those of electrodeposited pure Zn coatings with identical experimental conditions demonstrating the enhanced protective characteristics of the ternary alloys during the test period in the model medium. The influence of the chemical and phase composition of the alloys on its corrosion resistance and protective ability is also commented and discussed.

Download Full-text

The Effect of CaCO3 Addition on Physical Properties of ZnO-Based Crystal Glaze

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.620.12 ◽

2012 ◽

Vol 620 ◽

pp. 12-16 ◽

Cited By ~ 2

Author(s):

Abdul Rashid Jamaludin ◽

Shah Rizal Kasim ◽

Zainal Arifin Ahmad

Keyword(s):

Electron Microscope ◽

Calcium Carbonate ◽

Scanning Electron Microscope ◽

Physical Properties ◽

Crystallization Temperature ◽

Xrd Analysis ◽

Sem Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Scanning Electron

The effects of calcium carbonate (CaCO3) addition on the physical properties of ZnO-based crystal glaze batches were investigated. Samples were fired at different gloss firing temperatures ranging from 1180-1220°C with 3 hours soaking at 1060°C crystallization temperature. X-ray diffraction (XRD) analysis identifiedthe crystal phase occurred as willemite (Zn2SiO4) and the scanning electron microscope (SEM) analysis indicated that willemite crystals are in the acicular needle like shape that formed spherulite. The intensities of willemite peaks decreased with CaCO3 addition and completely vanished at 5.0 wt% CaCO3. Varied formation of spherulites developed of the surface of crystal glaze as the flows of the glaze stretched further as the amount of CaCO3 increased.

Download Full-text

A novel Mg-Sn-Zn-Al-Mn magnesium alloy with superior corrosion properties

Metallurgical Research & Technology ◽

10.1051/metal/2021064 ◽

2021 ◽

Vol 118 (5) ◽

pp. 504

Author(s):

Ali Ercetin

Keyword(s):

Protective Layer ◽

Xrd Analysis ◽

Production Method ◽

Sintering Process ◽

X Ray Diffraction ◽

Alloying Element ◽

Corrosion Properties ◽

Corrosion Behaviors ◽

Element Addition ◽

Hank’S Solution

The corrosion behaviors of the hot-pressed Mg-Sn-Zn-Al-Mn magnesium alloys with the addition of Al in different proportions have been investigated. Paraffin coating technique was applied to Mg powders before production. After debinding at 300 °C, the sintering process was applied at 610 °C under 50 MPa pressure for 70 min. All of the alloys were immersed in Hank’s solution for 10-days. The results indicated that the corrosion properties of the alloys were affected by the production method (hot pressing) and alloying element addition. After immersion, magnesium hydroxide (Mg(OH)2), hydroxyapatite (HA), and Mg-Al hydrotalcite structures were determined by the X-ray diffraction (XRD) analysis on the surfaces of Mg-Sn-Zn-Al-Mn alloys. The Mg-Al hydrotalcite protective layer was effective in preventing corrosion. Superior corrosion properties (weight loss: 1.2%, total volume of evolved H2 gas: 4 ml/cm2, corrosion rate: 0.39 mm/year) were obtained from TZAM5420 alloy (5 wt.%Sn, 4 wt.%Zn, 2 wt.%Al, 0.2 wt.%Mn).

Download Full-text