Hunting for Toxic Industrial Chemicals: Real-Time Detection of Carbon Disulfide Traces by Means of Ion Mobility Spectrometry

Sensitive real-time detection of vapors produced by toxic industrial chemicals (TICs) represents a stringent priority nowadays. Carbon disulfide (CS₂) is such a chemical, being widely used in manufacturing synthetic textile fibers and as a solvent. CS₂ is simultaneously a very reactive, highly flammable, irritant, corrosive, and highly toxic compound, affecting the central nervous system, cardiovascular system, eyes, kidneys, liver, skin, and reproductive system. This study was directed towards quick detection and quantification of CS₂ in air, using time-of-flight ion mobility spectrometry (IMS); photoionization detection (PID) was also used as confirmatory technique. Results obtained indicated that IMS can detect CS₂ at trace levels in air. The ion mobility spectrometric response was in the negative ion mode and presented one product ion, at a reduced ion mobility (K₀) of 2.25 cm² V⁻¹ s⁻¹. Our study demonstrated that by using a portable, commercial IMS system (model Mini IMS, I.U.T. GmbH Berlin Germany) one can easily measure CS₂ at concentrations of 0.1 ppm_v (0.3 mg m⁻³) in the negative ion mode, which is below the lowest threshold value of 1 ppm_v given for industrial hygiene. A limit of detection (LOD) of ca. 30 ppb_v (0.1 mg m⁻³) was also estimated.

Highly-sensitive carbon disulfide on-line detection system based on deep ultraviolet absorption spectroscopy, and its application in liquid-seal reliability assessment

This paper investigated a potential instrument for carbon disulfide in situ measurement with high precision and strong anti-interference capability. A compact and automated carbon disulfide detection system was developed using a fiber opto-electronic sensing device. A custom software interface based on LabVIEW was developed. The multi-wavelength least-squares method based on differential optical absorption spectroscopy was employed for improved detection and the anti-interference capabilities of the system. The detection limit of the system (signal-to-noise ratio=3) was determined to be 1 ppb per meter. Using this scheme, the reliability of a liquid-seal was verified to have carbon disulfide leakage. Although the liquid level of the liquid-sealed carbon disulfide showed no significant change over 24 h, a residue concentration of over 30 ppm remained detectable on the surface.