Analysis and instrument control is via simple, intuitive browser-style software. These deliver precise, high resolution wet and dry measurements with better than 1% accuracy and reproducibility. These include the Mastersizer 30E from Malvern Panalytical. This technique is capable of measuring particles from 10nm to 3500 microns.ĪTA Scientific supplies a range of particle sizing instruments that employ laser diffraction technology. These scattering patterns are measured by the detectors and particle size distribution is determined from the resulting data. Larger particles bring about a high intensity of scattering at low angles to the beam, smaller particles create a low intensity signal at much wider angles. The laser light is scattered in a variety of angles. The particles are dispersed in a liquid (often water) or air and illuminated by a collimated laser beam. This means it provides a result for the whole sample rather than for individual particles. Laser diffraction is an ensemble technique of particle sizing. It is a rapid, highly reproducible measuring technique which provides particle size distribution over a wide particle diameter range. shape as well as size), then image analysis methods are the only way to gain the extra information.Ĭontact ATA Scientific today for a free consultation.Laser diffraction, also known as Low Angle Laser Light Scattering (LALLS), is widely used for particle size analysis and is the standard method in many industries. And if you need to measure morphological properties of particles, (ie. < 0.5um), Dynamic Light Scattering is by far the easiest methods to use. Sieving is one of the oldest particle sizing methods and is still widely used for relatively large particles (ie. There are many other methods for analysing particle size, other than laser diffraction. It is also a very fast, reliable and reproducible technique and can measure over a very wide size range. Laser diffraction has become very popular because it can be applied to many different sample types, including dry powders, suspensions, emulsions and even aerosols. the smaller the particle size, the larger the angle of light scattering). It works on the principle that when a beam of light (a laser) is scattered by a group of particles, the angle of light scattering is inversely proportional to particle size (ie. Laser diffraction has become one of the most commonly used particle sizing methods, especially for particles in the range of 0.5 to 1000 microns. Probably the most common method is to measure the “volume” of each particle in a sample and report the size of a sphere which has the same volume as the particles being measured (this is what is done in Laser Diffraction methods). One example is to measure the surface area of a particle and then report the size of sphere which has the same surface area. We cannot say the same for a cube, where the 100 micron may describe the length of one edge, or even a diagonal transect.įor this reason, all particle sizing techniques measure a one dimensional property of a particle and relate this to the size of an “equivalent sphere”. If we say we have a 100 micron sphere, this describes it exactly. Only a sphere measures the same across every dimension. However, the difficulty with this is that there is only one shape that can be described by a single unique number, and that is the sphere. particle size on the x-axis and quantity of material on the y-axis). Most particle sizing techniques aim report particle size distributions on a two dimensional graph (ie. One basic problem in particle size analysis is characterizing particles using just one number. Some industries and product types where particle sizing is used includes: In just about every industry where milling or grinding is used, particle size is a critical factor in determining the efficiency of manufacturing processes and performance of the final product. Particle size analysis is a very important test and is used for quality control in many different industries. It is quite important to select the most suitable method for different samples as different methods can produce quite different results for the same material. Some particle sizing methods can be used for a wide range of samples, but some can only be used for specific applications. There are many different methods employed to measure particle size. Particle size analysis can be applied to solid materials, suspensions, emulsions and even aerosols. Particle size analysis is used to characterise the size distribution of particles in a given sample.
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