BENCHTOP EDXRF APPLICATIONS
APPLICATIONS THAT BENEFIT FROM THE RANGE, POWER AND SPEED OF THE ELVATECH BENCHTOPS
Museum curators, art historians, and archeologists must be constantly alert to forgeries. XRF is a great tool for them since it can identify the specific elemental composition of rare and valuable items without damaging them.
The legacy of the material can be determined as well allowing archeologists to identify trade routes. Since many works of art and artifacts can be quite large and must be kept as intact as possible, very large open beam XRF analyzers are built for this application.
Some of the open beam systems use µXRF optics for small spot analysis. Other more standard form factors of XRF instruments can be used as well when sample size is not a problem.
Here are a few common art applications:
- Paintings-Many paints contain metallic pigments such as cadmium or titanium, and even if they do not they may contain elements like calcium potassium and sulfur that can be used to identify a type of paint that an artist or tribe was known to use.
- Metals-The study of developments in metals and metalworking, particularly metal jewelry, has long been important to archeology. XRF is an ideal instrument for metals analysis, since every element can be identified, and fundamental parameter methods work there best with alloys. Metal alloys and metal making techniques change over time so forgeries and reproductions can often be identified by a detailed compositional analysis.
- Pottery and Ceramics-Ceramics contain elements that are usually indicative of a region, while glazes often contain metal dies that can be measured by XRF.
- Precious Stones-The origin of precious stones can often be identified by their elemental composition. Rubies for example contain traces of vanadium that differ by a hundred PPM or more depending on their source.
- Stone-It is usually possible to identify the quarry or region that stone comes from. Stone used in buildings or larger artwork like sculptures can be readily categorized by XRF. Artifacts made from stone, like flint points, axe heads, and shards can be identified by XRF. This information is useful for identifying trade routes.
- Wood and Plant Derived Material-Wood and other plant material also contains a variety of elements such as sulfur, potassium and calcium that can be used for identification purposes. Items such as canvas, wicker, and fabric can also be analyzed by XRF and at least partially fingerprinted.
The chemical and petrochemical market offers a diverse array of applications. While many processes involve organics that are not readily measured by XRF, there are many instances where salts or metals are important.
Here are a few common chemical applications:
- Curing Agents-Elements like sulfur and phosphorus are present in curing agents. These are usually present at high enough levels for XRF analysis.
- Metal Catalysts-Catalysts are used in a substantial number of chemical processes since they reduce both time and energy requirements. Many catalysts are valuable metals like platinum or palladium, so it is important to use the minimum quantities necessary. XRF is an ideal method for monitoring metal catalysts with laboratory, bench top, or on-line instrumentation.
, COATING AND THIN FILMS
Proper quality control of coating thickness is important to the plating companies and metal finishers that are applying the coatings and also affect the companies that utilize the plated components in their manufactured goods.
Product liability requires quality control to avoid defective coatings and eliminate problems, such as rust, that can lead to production problems or product recalls.
XRF spectrometers can be calibrated for determining both coating thickness and coating quality for many types of material. X-rays achieve superior penetration depths and so can measure coatings that other techniques cannot. If the coatings are predominantly one element, it makes the analysis very easy. Here are a few common coating applications:
- Silicone on Paper, Tissue Paper, Clay Coated paper, BOPP and Hygiene products-Silicone is used as a release coating on paper, so that adhesive labels do not stick. Silicone is used on tissue paper to make it feel softer. Silicone is also used in the liners of diapers and other hygiene products to repel moisture to keep the side next to the skin dry. EDXRF instruments are ideal for these applications.
- Platinum Catalyst in Silicone Resin-Platinum catalysts are used in silicone as a curing agent. It is added at concentration in the 100PPM range and can be analyzed by EDXRF.
- Phosphorus on Steel- Phosphate coatings are used to protect and pre-treat steels. They can be measured along with iron and manganese that is sometimes present. EDXRF is also used for monitoring the baths either by sampling it or by an on-line XRF instrument.
- Sulfur and Phosphorus on Aluminum- Aluminum is coated or anodized by etching the surface with an acid. Acid bonds to the aluminum making it much harder. The coating can be measured by EDXRF by measuring the elemental sulfur or phosphorus on the surface. Alternatively it can be measured by an x-ray absorption technique since the aluminum signal decreases with thicker anodized coatings.
- Copper on Silicon-Now that many silicon wafer fabricators are switching to copper, monitoring them with XRF is easier than ever. EDXRF is usable for on-line process monitoring.
- Capacitors-Modern capacitors like tantalum capacitors are made by coating a thin polymer with a thin layer of metal, then the material is rolled to form the capacitor. Aluminum is the most common metal, with tantalum holding an important niche. A variety of polymers are used including polyester (Mylar), polypropylene, and polycarbonate. EDXRF instruments are ideal for monitoring the metal film thickness. The polymer thickness can also be measured using x-ray absorption techniques.
- Metalized Food Packaging-Many foods are packed in foil pouches made from a polymer coated with metal. The oldest is aluminized Mylar, but titanium and zinc are common, and other polymers can be used. While light transmission is used for many thing coatings, EDXRF instruments are suitable for most applications, particularly with thicker coatings.
- Solar Power Cells- Most solar cells use thin coatings of a metal alloy on a polymer substrate. These coatings can be measured by EDXRF.
- Conductive Coatings on Plastic-In order to comply with regulations on electrical noise, modern plastic cases for electronic equipment must be shielded. Shielding is often achieved by coating the plastic with a conductive layer. In many instances this layer can be analyzed by EDXRF.
- Vapor and e-Beam Deposition Coatings- Numerous elements are deposited in thin films by e-beam or vapor deposition methods. Virtually every element above atomic number 10 can be measured by EDXRF.
During the manufacturing process, cosmetics need to be chemically analyzed to ensure conformance to product specification and safety as well as cost-effective manufacture.
The cosmetic market lends itself to the XRF method since many additives in cosmetics are mineral or metallic in nature, or are organics with a heavier element attached that is measurable by XRF. Here are a few well-known applications:
- Titanium and Zinc in Sunscreen-Titanium dioxide is used in most sunscreens to help prevent UV radiation burns. The concentration is high and easily measured by XRF. Zinc is also used in sunscreens as a UV blocking agent.
- Iron, Titanium, and Zinc in Base Makeup-Flesh colored base makeup usually contain black iron oxide, red iron oxide, and titanium dioxide and/or zinc oxide which are white. The ratio of these oxides determines the shade. XRF has been used to measure total iron, and other major components.
- Toxic Metals in Cosmetics-Cosmetic component are usually analyzed for toxic components to ensure that they are safe. XRF analyzers can be used for measuring toxic metals such as lead, cadmium, mercury, and arsenic in cosmetic products.
- Metal Dyes in Cosmetics-Some of the brightly colored dyes like those in eye shadows and fingernail polishes contain metallic dyes that can be measured by XRF.
There are numerous regulations in place that limit the amount of toxic compounds and metals that can be released into the atmosphere. XRF lends itself to many important analytical applications in support of these regulations.
Here are a few common environmental applications:
- Lead in Paint-Lead was long used in paint until it was found to be a leading cause of lead poisoning among children and people who work on the exteriors of older buildings. Thousands of hand held EDXRF instruments have been sold to meet lead in paint monitoring regulations.
- Air Filter Analysis-Internationally there are many air monitoring programs that look for respirable particulates in the air. They analyze for every conceivable element with close attention being paid to toxic metals. High-resolution EDXRF instruments with large quantity sample changers are made for this application.
- Soil Screening and Analysis-At wood treating facilities chromium, arsenic and pentachlorophenol may seep into the ground; in plating shops it may be chromium, while toxic metals such as lead, mercury, arsenic and cadmium contaminate numerous other sites. XRF is commonly used as a screening tool to identify grossly contaminated areas that must be remediated. Smaller EDXRF instruments, even hand held devices might be used on site, while higher end instruments are used in the lab.
- On-site and Stack Air Monitoring-Workers are often exposed to toxic particulates in the air like lead or uranium. A portable air sampler can take field samples that can be analyzed by a portable or laboratory XRF instrument. Similar samples air taken at stacks to monitor industrial emissions. The sampling system can be integrated to make this an on-line application as well. Some elements such as sulfur can be measured directly in the vapor phase.
- Waste Water-XRF can be used for analyzing metals in wastewater, such as silver emulsion from a photo lab.
- Tissue Samples-Tissue samples are monitored for toxic metal contamination as a way to monitor the safety of the environment. Fish are commonly analyzed for metals like mercury in order to determine water quality and ascertain if the fish are edible.
- PCB’s in soil-In areas of know PCB contamination where the soil is naturally low in chlorine, XRF can be used as a screening tool for PCB’s.
Food is a market that offers many opportunities for XRF. Samples can be measured as loose powders or pressed into pellets and ready for measurement within seconds.
There are a number of minerals and metals added for extra nutritional value that must be monitored to comply with food administration regulations.
The XRF method can not only reduce manufacturing costs but also improve food quality and help to safeguard human health and even lives. There are a number of established applications already:
- Chlorine in snack foods-Chlorine is monitored to control taste or assure compliance with low salt labeling of products. Snack foods like potato chips, processed meat and cheese that are often high and salt have been successfully analyzed by XRF.
- Iron and Selenium in Flour, Rice and Other Grain- Grains and processed flour have long been fortified with iron, and XRF instruments are used to monitor it.
- Calcium in Orange Juice, Cheese, and Other Foods-Calcium has long been added to orange juice, and is frequently added to many foods as a supplementary source of calcium for the prevention of osteoporosis.
- Titanium and Cookies and Snack Cakes-Titanium dioxide is used to make cookies cakes and fillings whiter and brighter. It is in pretty high concentration and is easily measured by XRF.
- Iron in Milk Powder-Iron is added to milk powder as a supplement, and is commonly analyzed by XRF.
- Na, Mg, P, Cl, K, Ca, Mn, Fe, and Zn in Pet Foods and Animal Feed-The nutritional value of pet foods and animal feed can be controlled by routinely monitoring the product with XRF.
- Al, and P in Dough-Aluminum and phosphorus are two more elements in addition to iron that are usually in dough and can be measured by XRF.
- Ash in Flour-The ash that remains when flour is burned is composed primarily of Na, Mg, K, and Ca oxides. The ash percentage and composition have an effect on taste and mouth feel of product made from flour, so they are routinely analyzed. XRF is an excellent method for performing this analysis
Forensic scientists generally require fast and non-destructive analysis of a very wide range of materials. Often these materials are presented in very small quantity, as evidence collected from a crime scene.
The elemental ‘fingerprint’ which XRF reveals is used to identify unknown materials, match crime scene materials to those found on suspects and provide vital information on explosive/gunpowder constituents.
The XRF method can identify a vast number of elements simultaneously it is an excellent tool for fingerprinting all kinds of materials analyzed in forensic analysis. Here are a few examples of material:
Paint, Glass, Ceramics, Metal, Soil, Plastic, Fabrics and Toxic Metals.
MINING AND METALS
XRF has played a major role in Mining – from exploration to finished product certifications and every process in between.
The shift towards lower-grade ore deposits, sustainable energy and volatile market conditions push the mining industry towards predictive, sustainable, and agile analytical solutions to improve safety, increase operational efficiency and develop new services and business models.
With years of experience in creating value for all different segments of the mining industry and developing essential methods to develop tailored solutions for an optimal and efficient prediction during all steps of your mining process – from mineral exploration to the analysis of final products.
Either direct analysis in the field, online sensors to predict ore grades, laboratory equipment
Ore sorting and grade control –
Iron ore mining
Copper, Nickel and Zinc Mining
Flotation Process Optimization
XRF offers efficient solutions for the analytical requirements for the determination of regulated substances in electrical and electronic equipment according to the European Directive RoHS (Restriction of Hazardous Substances in Electrical and Electronic Equipment) and WEEE (Waste Electrical and Electronical Equipment).
The RoHS directive restricts the use of the hazardous metals cadmium, lead and mercury as well as hexavalent chromium and the brominated flame retardants containing PBB and PBDE. The WEEE directive simultaneously regulates the minimum quotas for the recycling and reuse of electrical and electronic waste, for which products containing low levels of harmful substances are an important prerequisite.