Factors in Processing Reclaimed Rubber

1928 ◽  
Vol 1 (1) ◽  
pp. 59-69
Author(s):  
P. S. Shoaff
Keyword(s):  
High Temperatures ◽  
Raw Materials ◽  
Chemical Properties ◽  
Minimum Amount ◽  
Physical And Chemical Properties ◽  
Future Developments ◽  
Large Particles ◽  
Long Time ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract Production of reclaimed rubber of uniformly good physical and chemical properties is dependent first upon judicious classification and blending of raw materials. Grinding to a state in which no large particles are present, but without an excess of fines, allows a minimum devulcanizing time at a given temperature, decreases the tendency to depolymerize to an objectionable extent, and reduces the requirement for softeners. These conditions facilitate further processing to a smooth product of good quality with the desired plasticity and with optimum compounding, milling, calendering, and tubing characteristics. Devulcanization at high temperatures tends to reduce the tensile slightly and to increase the elongation as compared with treatment at lower temperatures. Alkali reclaims require efficient washing to remove residual caustic and the recovery of fines from the wash liquors involves problems of settling and filtration or screening. Drying of wet-processed reclaims at high temperatures or for an excessively long time results in tacky products, just as does over-devulcanization. A minimum amount of milling and refining at normal temperatures is desirable to preserve the quality, therefore previous processing should be thorough and uniform. Some comparisons of types of equipment are made and some desirable future developments are discussed.

Diesel Biofuels - Preparation, Characterization and Testing

2008 ◽  
Vol 59 (11) ◽  
Author(s):  
Cristina Dusescu ◽  
Anca Borcea ◽  
Vasile Matei ◽  
Ion Popa ◽  
Irina Gabriela Radulescu
Keyword(s):  
Vegetable Oils ◽  
Sunflower Oil ◽  
Raw Materials ◽  
Chemical Properties ◽  
Soya Bean ◽  
Production Unit ◽  
Physical And Chemical Properties ◽  
Physical And Chemical ◽  
And Chemical Properties

The present paper studies biodiesel samples preparation by transesterification and compares their physical and chemical properties (biofuels prepared from different raw materials - vegetable oils: sunflower oil, crocus oil and soya bean oil) and the biodegradability degree, as well as the possibilities of the integration of such production unit in industrial diagram of auto fuels production.

scholarly journals Influence of temperature regimes of ripening and fermentation stages on the physical and chemical properties of cream and sour-cream butter quality indicators

2018 ◽  
Vol 12 (3) ◽  
Author(s):  
O. O. Bondarchuk
Keyword(s):  
Milk Fat ◽  
Raw Materials ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Second Stage ◽  
Temperature Regimes ◽  
Third Stage ◽  
Sour Cream ◽  
Physical And Chemical ◽  
And Chemical Properties

Physical and chemical properties of cream multistep modes of ripening and fermentations are investigation and their role in the production of sour-cream butter is studied. The process of ripening of cream was carried out multistep, regimes were selected depending on seasonal changes in the composition of milk fat. For raw materials of the autumn-winter period, for the values of iodine number 29.1–34.5, the first stage of ripening was carried out at a temperature of 8°C for 2 hours, the second stage – at 21°C for 7 hours, the third stage – at 13°C for 10 hours. For raw of spring-summer period, for the values of iodine number 34.5–40.1, the first stage of ripening was carried out at 21°C for 6 hours, the second stage – at 13°C for 4 hours, the third stage – at 8°C for 8 hours. It has been established that individual modes of low-temperature cream preparation, taking into account seasonal changes in the composition of milk fat, make it possible to obtain cream before churning almost with the same indexes of effective viscosity. The content of the crystalline phase of milk fat under both temperature regimes was 38.7–40.1%, which is sufficient to obtain of proper consistency sour-cream butter. The content of diacetyl and volatile organic acids more depend on the level of fermentation of cream than on the technological regimes of ripening and seasonality of raw materials. It has been proved that an increase in the fermentation degree of cream promotes an increase in the acidity of plasma and the content of aroma-producing components in the butter, and, accordingly, affects the degree of the sour taste. It is recommended for the production of cultured butter to begin the cream when the acidity of the plasma reaches 60ºT, which ensures the formation of high sensorial characteristic of the finished product.

Vegetable oils – raw materials for producing biodiesel

2021 ◽  
Vol 80 (2) ◽  
pp. 286-292
Author(s):  
T. Mamilov ◽  
◽  
G.S. Aitkaliyeva ◽  
A.B. Ismailova ◽  
M.A. Yelubay ◽  
...  
Keyword(s):  
Functional Groups ◽  
Vegetable Oils ◽  
Raw Materials ◽  
Chemical Properties ◽  
Biodiesel Fuel ◽  
Physical And Chemical Properties ◽  
Sunflower Oils ◽  
Transesterification Method ◽  
Physical And Chemical ◽  
And Chemical Properties

This paper presents the results of a study of the physical and chemical properties of samples of vegetable oils (sunflower, rapeseed, olive). It has been shown that the viscosity of oils varies from 41.4 to 61.7 cSt at a temperature of 40 ° C for olive and sunflower oils, respectively. The acid numbers of the oil samples were also determined, it was found that the lowest indicator is characteristic of sunflower oil. Pour points of oils also range from -3 to -16 ° C for olive and sunflower oils, respectively. Using the method of IR spectroscopy, functional groups in the composition of samples of vegetable oils were studied and it was shown that the composition of oils contains carbonyl and hydroxyl functional groups, indicating the presence of carboxylic acids. Based on studies of the physical and chemical properties of vegetable oils, it was found that sunflower, olive and rapeseed oils can serve as raw materials for the synthesis of biofuels based on them, since they contain free fatty acids. To obtain biodiesel fuel based on vegetable oils, it is planned to use the transesterification method in the presence of various catalysts (alkaline, acidic, and complex).

Effects of Preparation of Cement Raw Meal with Carbide Slag on the Environment and Equipments

2014 ◽  
Vol 787 ◽  
pp. 123-127 ◽  
Author(s):  
Ya Li Wang ◽  
Su Ping Cui ◽  
Hui Wang ◽  
Shi Jie Dong ◽  
Yan Yao
Keyword(s):  
Heavy Metal Ions ◽  
Raw Materials ◽  
Chemical Properties ◽  
Exhaust Gas ◽  
Physical And Chemical Properties ◽  
Drying Process ◽  
Calcination Process ◽  
Carbide Slag ◽  
Physical And Chemical ◽  
And Chemical Properties

Based on the physical and chemical properties of carbide slag, the contents of heavy metals in effluent came from carbide slag drying process were studied, and then the composition of exhaust gas emitted from the carbide slag drying process and calcinations process of raw materials prepared with carbide slag was detected, in order to know whether there are harmful or corrosive gases released and the effect of the emissions on the environment and related equipments. The results indicate that the exhaust gases emitted from the calcination process of raw meal prepared with carbide slag is mainly composed of CO2 and water vapor, and is free from harmful gases. However, a lot of water in carbide slag during the pre-heat and decomposition process under high temperature would accelerate the corrosion of equipments. Simultaneously, a small number of heavy metal ions contained in the carbide slag can cause environmental pollution and sulfides would be adverse to the cement calcination process resulting in the crust blockage of kiln.

Effects of Waste from HDPE Catalyst Process on Melting Behaviour and Thermal Properties of White Opaque Glazes

2014 ◽  
Vol 608 ◽  
pp. 97-102 ◽  
Author(s):  
Suneeporn Pokaew ◽  
Wantanee Buggakupta ◽  
Thanakorn Wasanapiarnpong
Keyword(s):  
Thermal Expansion ◽  
High Density Polyethylene ◽  
Fine Particles ◽  
Raw Materials ◽  
Linear Thermal Expansion ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Melting Behaviour ◽  
Physical And Chemical ◽  
And Chemical Properties

Polyolefin catalyst wastes have been rising with growing high density polyethylene (HDPE) demand. Utilizing on recycling such waste residue has then become a challenging task to achieve. Due to its relatively fine particles, iron oxide-free and consistent composition, the waste can possibly be another alternative for ceramic glaze raw materials. This study observed the replacement of the waste to the conventional glaze raw materials. The residue mainly contains TiO2 along with CaO, Al2O3 and a small amount of chloride. Physical and chemical properties of the waste were characterized. The roles of the waste on melting behaviour and appearance were observed. Colour of the introduced waste-containing glaze was determined by a spectrophotometer. Finally, coefficient of linear thermal expansion of the obtained glazes was done by a dilatometer. Characteristics of the waste-bearing white opaque glazes were reported and discussed.

scholarly journals Isolation and determination of some physical and chemical properties of polysaccharide from black elderberry flowers

2020 ◽  
pp. 95-101
Author(s):  
Игорь Анатольевич Сычев ◽  
Татьяна Викторовна Алимкина
Keyword(s):  
Medicinal Plant ◽  
Quantitative Determination ◽  
Raw Materials ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Plant Raw Materials ◽  
Physical And Chemical ◽  
And Chemical Properties

Предложенный метод количественного определения восстанавливающих моносахаридов в полисахариде позволяет проводить стандартизацию лекарственного растительного сырья цветков бузины черной. На способ стандартизации лекарственного растительного сырья цветков бузины черной по содержанию восстанавливающих моносахаридов в полисахариде оформлено рационализаторское предложение № 1373 от 29.02.2016 г. РязГМУ. The proposed method for the quantitative determination of reducing monosaccharides in a polysaccharide makes it possible to standardize medicinal plant raw materials of black elderberry flowers. On the method of standardization of medicinal plant raw materials of black elderberry flowers in terms of the content of reducing monosaccharides in the polysaccharide, a rationalization proposal No. 1373 dated February 29, 2016 RyazSMU was issued.

scholarly journals Problems in fuelling spark ignition engines with dimethyl ether

2017 ◽  
Vol 170 (3) ◽  
pp. 154-158
Author(s):  
Stanisław KRUCZYŃKI ◽  
Marcin ŚLĘZAK ◽  
Wojciech GIS ◽  
Piotr ORLIŃSKI ◽  
Andrzej KULCZYCKI ◽  
...  
Keyword(s):  
Dimethyl Ether ◽  
Diesel Fuel ◽  
Raw Materials ◽  
Chemical Properties ◽  
Spark Ignition Engines ◽  
Physical And Chemical Properties ◽  
Plant Raw Materials ◽  
Harmful Substances ◽  
Physical And Chemical ◽  
And Chemical Properties

This paper discusses briefly the production technology of dimethyl ether, taking into account plant raw materials and the physical and chemical properties of DME as compared to diesel fuel. The benefits and disadvantages of DME as a fuel are presented and changes in the emission of harmful substances characterised as compared to the combustion of diesel fuel. Also, basic usage problems are addressed, e.g. the wear of engine’s elements, cavity and leakages in the fuel system.

scholarly journals Two-Dimensional Semiconductor Heterojunctions for Optoelectronics and Electronics

2021 ◽  
Vol 9 ◽  
Author(s):  
Qian Wang ◽  
Lin Zhang ◽  
Xuejuan Liu ◽  
Sha Li
Keyword(s):  
Electric Fields ◽  
Chemical Properties ◽  
Band Alignment ◽  
Physical And Chemical Properties ◽  
Two Dimensional ◽  
Layered Semiconductors ◽  
Future Developments ◽  
Device Applications ◽  
Physical And Chemical ◽  
And Chemical Properties

Two-dimensional (2D) layered semiconductors are current research hotspots on account of their wide variety of applications in electronics and optoelectronics due to their particular ultrathin nature. In this review, the band alignment engineering in heterojunctions composed of 2D van der Waals (vdW) layered semiconductors and their device applications in optoelectronics are provided. Various approaches that induced adjustability of vdW heterojunctions are summarized, mainly including composition and thickness modulations, strain, and electric fields. Furthermore, their perspectives on future developments in optoelectronics and electronics devices based on the newly unique physical and chemical properties are outlined.

Sign in / Sign up

Export Citation Format

Share Document