Química / Plásticos
No. 32
PDF-Download:
PREPARACIÓN DE MUESTRAS para el análisis instrumental
- Metales pesados en juguetes
- Determinación de grasas en alimentos y forrajes
- Detección de micotoxinas en nueces
- Preparación de muestras para XRF
- Análisis granulométrico de piezas molturadoras
GANE PRODUCTOS DE ALTA CALIDAD “MADE IN GERMANY”
¡El primer premio es un Mercedes deportivo!
Además sorteamos cada dos meses valiosos premios, por ej. una bicicleta Mercedes o una cámara digital Leica de 10 megapíxeles.
WWW.RETSCH.ES/GRANDPRIX
Application Database
Testimonials (3)
-
Catalysts for Improved Fuels - Shell Global Solutions
-
Preparation of plastic parts - imat uve
-
Quality Control of Limestone - Schaeferkalk
Informes técnicos (28)
Powerful Cutting Mill
The SM 300 excels especially in the tough jobs where other cutting mills fail. It has a freely selectable speed range from 700 to 3,000 rpm with high torque. The mill is convenient to operate and easy to clean. Reliable and extremely efficient sample preparation in the laboratory is now guaranteed with the SM 300.
Representative results require adequate sample preparation
The following situation is typical for many production plants: After a routine quality check, the production process is stopped or an already produced batch is suspended, because the analysis results were not within the relevant critical values. But does the tested product really deviate from the specifications? The quality control managers are convinced of this because modern analysis instruments provide results with very low tolerances. The sample in question was tested several times and the result was confirmed. The question is why the product does not match the specifications although the production parameters have not been changed in any way.
The possibility that the tested product is indeed deficient cannot be excluded. However, it is often not the product itself which causes irregular analysis results but a lack of understanding of the steps which come before the analysis.
Sieving of agglomerating powders with the air jet sieving machine AS 200 jet
Air jet sieving is usually the method of choice for dry sieving of materials with particle sizes below 40 microns. However, it is also a faster alternative to vibratory sieving of materials of up to 250 microns.
Preparation of Elastic Plastics for the Detection of PAH
Polycyclic aromatic hydrocarbons, short PAH, are usually a by-product of combustion and can be found, for example, in cigarette smoke or oil-based products. Mineral oil containing PAH is often used in rubber products as plasticizer, especially in black-coloured products such as car tyres, rubber grips of tools or rubber shoe soles. It was discovered that some polycyclic aromatic hydrocarbons are carcinogenic, so that maximum permissible values have been determined for the concentration of PAH in consumer products.
Size reduction of elastic plastics with volatile components
Neutral-to-analysis sample preparation for the detection of PAH and phthalates
Air Jet Sieving of Bulk Materials
Particle size analysis and particle size distribution are important criteria for the quality control of bulk materials. In a running production process, the results of a quality check must be available quickly to allow for immediate adjustment of the production parameters. Depending on the expected particle size and sample volume, different sieving methods and sieving machines are suitable for analysis. The method used for particle size analysis is primarily determined by the fineness of the material to be sieved. For dry sieving of samples with particle sizes below 40 microns, air jet sieving is the method of choice.
Using the CryoMill for samples with volatile substances
For the size reduction of many materials it is more suitable to use a cryogenic mill than a laboratory mill which operates at room temperature. The sample is embrittled by liquid nitrogen which improves its breaking behavior when submitted to impact, pressure and friction; moreover, volatile components of the sample are preserved. The RETSCH CryoMill is not only the most modern and safest cryogenic mill in the market, it also provides excellent grinding results.
Cutting Mill SM 300 - Refinement of a well-proven grinding principle
Cutting mills are used in many different areas of sample preparation for subsequent analyses. Typical applications include the size reduction of secondary fuels, the processing of biomass for renewable energy research, the control of products in the context of RoHS and WEEE regulations or the recovery of precious metals – the variety of sample materials is huge.
Efficient Grinding at –196 °C
RETSCH’s New CryoMill for Safe and Reproducible Grinding with Liquid Nitrogen
Green Chemistry in the Lab
Mechanochemistry is a very effective method to carry out syntheses without solvents and by-products. The technical literature describes a great number of reactions where a conversion of 100% is achieved. A precondition for the establishment of mechanochemistry in the industrial sector is the availability of suitable laboratory mills. A decisive factor is that – similar to conventional preparative chemistry – ambient parameters such as pressure and temperature can be documented and monitored. The Planetary Ball Mills and Mixer Mills from Retsch fulfill these requirements.
Tracking down hazardous substances (RoHS/WEEE)
Preparing electronic waste for obtaining representative analytical samples.
A solution for converting an electrical appliance into a meaningful analytical sample is described using a remote-controlled toy car as an example.
La Fragmentación
Por lo general se asocia a la noción "fragmentación", el machacamiento, de sustancias sólidas mediante fuerza mecánica. Pero también la división de líquidos en gotas o de gases en bollas representa un proceso de fragmentación.
Sample Preparation of Electronic Scrap in the Context of RoHS and WEEE
Since August 2004 new EU directives for the disposal of used electrical and electronic appliances as well as the restricted use of certain hazardous substances in these devices have become effective.
Consistent Milling on a Nano Scale
Planetary ball mills are helping scientists and engineers advance nanotechnology by providing a consistent way to produce nanoscale powders.
Sample Preparation of Plastics for X-Ray-Fluorescence Analysis
The elemental analysis of plastics has become more and more important. EC directive 91/338/EWG regulates the ban of cadmium in PVC, EC directive 94/62/EC defines limits for cadmium, lead, chromium and mercury in packing materials and EC directive 2000/53/EC defines limits for the same elements in end-of-life vehicles. This has created a strong need for a rapid and reliable testing method.
Cryogenic Preparation of Sample Materials
Within the context of sample preparation, size reduction plays an important role as it has a substantial influence on the results of the subsequent analysis. If the particles are too coarse or non-homogeneous the results of the analysis may turn out to be incorrect, especially if there is only a very small amount of sample material which represents the total amount.
Analysis of cadmium in plastics
In recent years, mass media have focused on the topics of the environment and environmental conservation. With the advancement in scientific technology, resource development has progressed.
Sample Preparation of Solid Materials for the XRF-analysis
X-Ray fluorescence is one of the most versatile methods to determine elements in a sample. The material is exposed to x-rays that cause each element to emit its own unique fluorescent x-ray. The subsequent analysis of the results is based on comparisons to standard samples with given chemical composition.
Herstellung von Nanopartikel mit der Planeten-Kugelmühle
Die Herstellung von Nanopartikeln, deren Größe im Bereich von 1 Mikron und kleiner liegt, ist in vielen technischen Bereichen immer mehr auf dem Vormarsch, denn sie ermöglichen die gezielte Veränderung von Materialeigenschaften.
La nueva generación de molinas planetarios de bolas
Los más precisos resultados de trituración en el más breve tiempo se consiguen con los nuevos molinos planetarios de bolas, de Retsch. Con el PM100 y el PM200, Retsch presenta una nueva generación de molinos planetarios de bolas con uno o dos unidades de trituración, que establecen nuevos estándares de rendimiento en este segmento de la producción.
Los especial del pigmento
Debido a la ilimitada variedad de colores y texturas que ofrencen los recubrimientos en polvo; muchos de los nuevos recubrimientosde aplicación especifica se crean en el laboratorio en pequeñas cantidades que luego se le envían al cliente para su aplicación y aprobación.
Molienda ultrarrápida y ultrafina
El nuevo molino ultracentrífugo ZM 200 de RETSCH es un molino de rotor no sólo extremadamente rápido y cuidadoso con el material molido, sino también de uso universal gracias a su amplia gama de accesorios.
Preparación de muestras altamente heterogéneas para el control de calidad
El agotamiento de los recursos y el aumento del precio de los combustibles primarios tales como el petróleo, el gas o el carbón han obligado a la industria del cemento a buscar fuentes alternativas de energía. Otro factor contribuyente es, sin duda, el comercio de emisiones que hace todavía más rentable el cambio a fuentes de energía con un balance neutro de CO2, en su mayoría combustibles no fósiles. En los últimos años, se ha registrado un incremento en el uso de fuentes de energía alternativas, especialmente por aquellas industrias con una alta demanda energética. En consecuencia, viene ganando cada vez más importancia el empleo de combustibles secundarios o alternativos, que en su mayoría son extraídos de residuos urbanos e industriales – es decir, residuos urbanos que no han podido ser recuperados ni reciclados.
Zusammenspiel der Kräfte
Planeten-Kugelmühlen ermöglichen mechanisches Legieren dank ihrer hohen Zerkleinerungsenergie
Mechanisch legierte Werkstoffe haben schon längst ihren Einzug in die moderne Werkstofftechnik gehalten. Viele neue Werkstoffe und Werkstoffkomposite wurden in den letzten Jahren durch intensive Forschung entwickelt und werden bereits industriell hergestellt. Mechanisches Legieren ist ein gängiges Verfahren, um Werkstoffpaarungen oder Komposite zu synthetisieren, die auf konventionellem Wege nicht realisierbar wären, wie z. B. das Verbinden von Natur aus unmischbarer Legierungspartner. Das Werkzeug der Wahl dafür sind Planeten-Kugelmühlen.
