scholarly journals Waste Mineral Wool and Its Opportunities—A Review

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5777
Author(s):  
Zhen Shyong Yap ◽  
Nur Hafizah A. Khalid ◽  
Zaiton Haron ◽  
Azman Mohamed ◽  
Mahmood Md Tahir ◽  
...  

Massive waste rock wool was generated globally and it caused substantial environmental issues such as landfill and leaching. However, reviews on the recyclability of waste rock wool are scarce. Therefore, this study presents an in-depth review of the characterization and potential usability of waste rock wool. Waste rock wool can be characterized based on its physical properties, chemical composition, and types of contaminants. The review showed that waste rock wool from the manufacturing process is more workable to be recycled for further application than the post-consumer due to its high purity. It also revealed that the pre-treatment method—comminution is vital for achieving mixture homogeneity and enhancing the properties of recycled products. The potential application of waste rock wool is reviewed with key results emphasized to demonstrate the practicality and commercial viability of each option. With a high content of chemically inert compounds such as silicon dioxide (SiO2), calcium oxide (CaO), and aluminum oxide (Al2O3) that improve fire resistance properties, waste rock wool is mainly repurposed as fillers in composite material for construction and building materials. Furthermore, waste rock wool is potentially utilized as an oil, water pollutant, and gas absorbent. To sum up, waste rock wool could be feasibly recycled as a composite material enhancer and utilized as an absorbent for a greener environment.

Author(s):  
E Y. Wang ◽  
J. T. Cherian ◽  
A. Madsen ◽  
R. M. Fisher

Many steel parts are electro-plated with chromium to protect them against corrosion and to improve their wear-resistance. Good adhesion of the chrome plate to the steel surface, which is essential for long term durability of the part, is extremely dependent on surface preparation prior to plating. Recently, McDonnell Douglas developed a new pre-treatment method for chrome plating in which the steel is anodically etched in a sulfuric acid and hydrofluoric acid solution. On carbon steel surfaces, this anodic pre-treatment produces a dark, loosely adhering material that is commonly called the “smut” layer. On stainless steels and nickel alloys, the surface is only darkened by the anodic pre-treatment and little residue is produced. Anodic pre-treatment prior to hard chrome plating results in much better adherence to both carbon and alloy steels.We have characterized the anodic pre-treated steel surface and the resulting “smut” layer using various techniques including electron spectroscopy for chemical analysis (ESCA) on bulk samples and transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS) on stripped films.


2019 ◽  
Vol 37 (No. 4) ◽  
pp. 246-251 ◽  
Author(s):  
Joanna Tkaczewska ◽  
Maciej Wielgosz ◽  
Piotr Kulawik ◽  
Marzena Zajac

The influence of drying temperature on the characteristics and gel properties of gelatine from Cyprinus carpio L. skin was studied. Gelatine was extracted from the carp skin using NaOH and ethanol pre-treatment method, extracted in water in 45°C and then dried in 4 different temperatures: 50, 70, 80°C and freeze-dried. The  electrophoresis and functional properties of gelatines were investigated. Freeze drying allowed to obtain a high gelling force, and all other methods did not give satisfactory results. The proteins in gelatines dried at higher temperatures separated by electrophoresis gave severely blurred bands. It may be explained by thermal hydrolysis of collagen fibrils. Freeze drying is the only effective method for drying this product, which can be used in industry.


Talanta ◽  
2007 ◽  
Vol 71 (3) ◽  
pp. 1172-1179 ◽  
Author(s):  
Y. Fajardo ◽  
E. Gómez ◽  
F. Garcias ◽  
V. Cerdà ◽  
M. Casas

Desalination ◽  
2010 ◽  
Vol 250 (2) ◽  
pp. 557-561 ◽  
Author(s):  
J.J. Lee ◽  
M.A.H. Johir ◽  
K.H. Chinu ◽  
H.K. Shon ◽  
S. Vigneswaran ◽  
...  

Author(s):  
Avinash V Borgaonkar ◽  
Ismail Syed ◽  
Shirish H Sonawane

Molybdenum disulphide (MoS2) is a popularly used solid lubricant in various applications due to its superior tribological behaviour. However, it possesses poor wear resistance which requires further improvement. In the present study efforts have been made to enhance the tribological properties of pure MoS2 coating film by doping TiO2 nanoparticles as a reinforcement material. The Manganese phosphating is selected as a pre-treatment method to improve the bond strength between coating and substrate. The coating is bonded with the substrate material employing sodium silicate as a binder. The effects of wt. % of TiO2 onto the mechanical properties of composite MoS2-TiO2 coating such as hardness and bond strength have been studied. In addition coating microstructure before and after experimental test was studied using optical microscope and scanning electron microscope. It was also found that with increase in wt. % addition of TiO2 upto 15% into MoS2 base matrix, the hardness of coating increases proportionally. Beyond 15 wt. % addition of TiO2, the coating becomes brittle in nature. This leads to reduction in the scratch resistance.


2021 ◽  
Author(s):  
Soo Takasu ◽  
Isabella Supardi Parida ◽  
Yoshihiro Kojima ◽  
Toshiyuki Kimura ◽  
Kiyotaka Nakagawa

We demonstrated the conversion of GAL-DNJ into DNJ improves mulberry leaves bioavailability and constructed a novel enzymatic-based method to induce the hydrolysis of GAL-DNJ to DNJ.


2011 ◽  
Vol 335-336 ◽  
pp. 1412-1417 ◽  
Author(s):  
Jiri Zach ◽  
Jitka Peterková ◽  
Vít Petranek ◽  
Jana Kosíková ◽  
Azra Korjenic

Production of building materials is mostly energy consuming. In the sphere of insulation materials we mostly see rock wool based materials or foam-plastic materials whose production process is demanding from material aspect and raw materials aspect as well. At present the demand for thermal insulation materials has been growing globally. The thermal insulation materials form integral part of all constructions in civil engineering. The materials mainly fulfill the thermal insulating functions and also the sound-insulating one. The majority of thermal insulation materials are able to fulfill both of the functions simultaneously. The paper describes questions of thermal insulation materials development with good sound properties based on natural fibres that represent a quickly renewable source of raw materials coming from agriculture. The main advantage of the materials are mainly the local availability and simple renewability of the raw materials. In addition an easy recycling of the materials after their service life end in the building construction and last but not least also the connection of human friendly properties of organic materials with advanced product manufacture qualities of modern insulation materials.


2020 ◽  
Vol 15 (3) ◽  
pp. 818-828
Author(s):  
Miradatul Najwa Muhd Rodhi ◽  
Fazlena Hamzah ◽  
Ku Halim Ku Hamid

Gallic acid and quercetin equivalent were determined in the crude extract of matured leaves Aquilaria malaccensis and Aquilaria subintegra. The leaves of both Aquilaria species were dried at 60 °C for 24 hours, ground and sieved into particle size of 250, 300, 400, 500, and 1000 µm. Then, each particle size of leaves was soaked in distilled water with a ratio of 1:100 (w/v) for 24 hours and undergoes the pre-treatment method by using ultrasonicator (37 kHz), at the temperature of 60 °C for 30 minutes. The crude extracts were obtained after about 4 hours of hydrodistillation process. The highest concentration of gallic acid and quercetin equivalent was determined in the crude extract from the particle size of 250 µm. The kinetics of pancreatic lipase inhibition was further studied based using the Lineweaver-Burk plot, wherein the concentration of p-NPP as the substrate and pancreatic lipase were varied. Based on the formation of the lines in the plot, the crude leaves extract of both Aquilaria species exhibit the mixed-inhibition on pancreatic lipase, which indicates that in the reaction, the inhibitors were not only attached to the free pancreatic lipase, but also to the pancreatic lipase-(p-NPP) complex. The reaction mechanism was similar to non-competitive inhibition; however the value of dissociation constant, Ki, for both inhibition pathways was different. The inhibition shows an increment in Michaelis-Menten constant (Km) and a reduction in the maximum pancreatic lipase activity (Vm) compared to the reaction without Aquilaria spp. crude extracts (control). This proved that the inhibition occurred in this reaction. Copyright © 2020 BCREC Group. All rights reserved 


2021 ◽  
Vol 31 (4) ◽  
pp. 249-255
Author(s):  
Zuoqun Zhang ◽  
Chaoshan Yang ◽  
Hua Cheng ◽  
Xiaohan Huang ◽  
Yuhao Zhu

Now there’re many researches on the electromagnetic radiation protection function of the cement-based electromagnetic wave absorbing materials, such materials have been widely used in various types of buildings. This paper proposed an idea for preparing a cement-based composite material by mixing functional aggregates with high content of Fe2O3 and SiC, that is, adding Fe3O4 powder and nano-SiC of different contents in the clay, and then sintering at 1190℃; the prepared aggregates showed obvious magnetic loss and dielectric loss to electromagnetic waves, and the numerical tube pressure could reach 16.83MPa. The double-layer reflectivity test board made of functional aggregates showed excellent electromagnetic wave absorption performance, its reflection loss was less than -10dB in the frequency range of 8~18GHz (corresponding to energy absorption greater than 90% EM), and its maximum RL reached -12.13dB. In addition, the compressive strength of the cement-based composite material at the age of 28 days reached 50.1 MPa, which can meet the strength requirements of building materials.


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