Skyray WDX3300 Dual-Curved Crystal Single-Wavelength Wavelength-Dispersive X-ray Fluorescence Spectrometer

Overview

The Skyray WDX3300 is a high-performance wavelength-dispersive X-ray fluorescence (WDXRF) spectrometer engineered for ultra-trace chlorine analysis in complex hydrocarbon matrices. Unlike energy-dispersive (EDXRF) systems, the WDX3300 employs Bragg diffraction-based monochromatic excitation and detection—utilizing a dual-curved crystal optics architecture to achieve secondary focusing of both primary and secondary X-ray beams. This design enhances photon flux density at the sample and detector positions, significantly improving signal-to-noise ratio for light elements—particularly chlorine (Cl Kα at 2.62 keV). The instrument operates on a fixed-wavelength principle: a Cr-target X-ray tube generates primary radiation, which is first monochromatized by a primary curved crystal to yield a highly collimated Cr Kα line (5.41 keV); this monochromatic beam then excites Cl Kα fluorescence in the sample, which is subsequently isolated via a secondary curved crystal and measured by a gas-flow proportional counter. This two-stage spectral filtering eliminates spectral overlap from sulfur (S Kα at 2.31 keV) and other interfering halogens (Br, I), enabling selective, matrix-resilient quantification of chlorine down to sub-ppm levels in petroleum streams.

Key Features

• Dual-curved crystal optics system providing double-focusing geometry for enhanced intensity and peak resolution
• Dedicated chlorine analysis channel with optimized Bragg angle configuration and vacuum-purged optical path (≤1 Pa residual pressure)
• Automated vacuum control and intelligent background subtraction algorithm for low-Z element stability
• Integrated thin-film sample presentation platform compatible with disposable polypropylene cups and 4-µm polymer films
• Pre-calibrated petroleum matrix library covering crude oil, diesel, jet fuel, lubricants, and biofuels per NB/SH/T 0977–2019
• Rugged mechanical design with temperature-stabilized goniometer and long-life sealed X-ray tube (≥20,000 h nominal lifetime)

Sample Compatibility & Compliance

The WDX3300 supports liquid, semi-solid, and solid samples—including homogenized oils, filtered aqueous extracts, pressed pellets, and thin-film deposits. All measurements are conducted under controlled vacuum conditions to minimize air absorption of low-energy Cl Kα photons. The system complies with NB/SH/T 0977–2019 for chlorine determination in light distillates and meets technical requirements referenced in ASTM D7260 (Standard Practice for XRF Analysis of Chlorine in Hydrocarbons) and ISO 8217 (Petroleum products — Fuels (class F) — Specifications). Full audit trail functionality supports GLP-compliant operation, including user authentication, method versioning, and raw-data immutability per FDA 21 CFR Part 11 guidelines when paired with optional LIMS integration.

Software & Data Management

The instrument is operated via Skyray’s proprietary SpectraTrace™ software, a Windows-based platform supporting method development, calibration curve generation (linear and quadratic), limit-of-detection (LOD) calculation per IUPAC recommendations, and statistical reporting (RSD, recovery %, confidence intervals). Data files adhere to ASTM E1397-compliant .spc binary format with embedded metadata (operator ID, timestamp, instrument parameters, environmental conditions). Export options include CSV, PDF analytical reports, and XML for enterprise-level data exchange. Software validation packages are available for regulated environments requiring IQ/OQ/PQ documentation.

Applications

• Petroleum refining: Quantification of organic chloride in crude feedstocks, naphthas, and hydrotreated fractions to prevent catalyst poisoning and stress corrosion cracking
• Environmental monitoring: Detection of chlorinated pesticides (e.g., DDT), PCBs, and chlorinated solvents in water, soil, and sediment extracts
• Chemical manufacturing: Purity verification of PVC resins, chlorinated intermediates, and pharmaceutical precursors
• Power generation: Chlorine screening in coal ash leachates and flue gas desulfurization slurries
• Construction materials: Chloride ingress profiling in concrete cores per ASTM C1152/C1556 for corrosion risk assessment
• Electronics: Trace chlorine contamination analysis in high-purity silicon wafers and photoresist formulations

FAQ

What detection limit does the WDX3300 achieve for chlorine in hydrocarbon matrices?

The instrument delivers a practical detection limit of 0.16 mg/kg (ppm) for chlorine in diesel and light distillates under standard 300-second counting time and vacuum operation.
How does the dual-curved crystal design mitigate sulfur interference?

By physically separating Cl Kα (2.62 keV) and S Kα (2.31 keV) through precise Bragg-angle tuning of two independent curved crystals, the system achieves spectral resolution sufficient to resolve these peaks without digital deconvolution.
Is method transfer possible between different WDX3300 units?

Yes—calibration models are portable across instruments of the same configuration when using certified reference materials traceable to NIST SRM 2721 or equivalent petroleum CRMs.
Can the system analyze solid samples such as catalyst powders or metal coupons?

Yes, provided samples are homogenized and presented as pressed pellets or thin films; optional accessories include hydraulic pellet press and film applicator kits.
Does the software support multi-element analysis beyond chlorine?

While optimized for single-wavelength chlorine quantification, the platform permits sequential measurement of up to five additional elements (e.g., S, Si, Ca, Ni, V) using interchangeable crystals and detectors—subject to hardware configuration.