Current analytical methods to quantify PAHs in activated carbon and vegetable carbon (E153) are not fit for purpose

Enhanced mitigation of inhalable particles and fine particle-bound PAHs from a novel hazardous waste-power plant candidate

Emissions of the inhalable particle (dp < 10 μm, PM10) and their harmful compositions from combustion sources have high potential on health risk with nearly no regulation. This study investigates the particle size distribution (PSD), as well as the removal mechanism of PM10 and fine particle (FP)-bound polycyclic aromatic hydrocarbons (PAHs) from the flue gas of a hazardous waste thermal treatment system. It has ultralow regulated emission and becomes a candidate of power generation module. A series of the advanced scrubbers, cyclonic demister, and baghouse was equipped for multi-pollutant control. The moderate or intense low oxygen dilution (MILD) combustion effectively inhibited the PM2.5 generation by volumetric oxidation. Advanced scrubbers removed PM1, PM2.5, and PM10 by 85.24, 68.68, and 97.60%, respectively, which achieved by local supersaturation, heterogeneous condensation of water vapor, and the growth of fine PM. Moreover, the scrubbers effectively scavenged the course PM10 containing the high-molecular-weight PAH homologs onto the water phase but promoted the condensation and absorption of the lighter homologs onto the fine particle surface (dp ∼5.3 μm). The size window (dp = 0.3-1.0 μm) of the minimum efficiency reporting value of a BH filtration led to the peak of FP-PAH mass and BaP equivalent (BaPeq) toxicity at dp = 0.1-0.4 and 0.1-0.8 μm, respectively. Consequently, the synergy of MILD combustion and the SCB-CYC-BH system effectively inhibited the PM2.5, PM10, PM2.5-PAHs, and FP-PAH levels from a waste thermal treatment process and further mitigated the potential health risk.

Determination of 31 Polycyclic Aromatic Hydrocarbons in Plant Leaves Using Internal Standard Method with Ultrasonic Extraction-Gas Chromatography-Mass Spectrometry

The method for the determination of 16 priority polycyclic aromatic hydrocarbons (PAHs) in plant leaves has been studied extensively, yet the quantitativemethod for measuring non-priority PAHs in plant leaves is limited. A method for the simultaneous determination of 31 polycyclic aromatic hydrocarbons (PAHs) in plant leaves was established using an ultrasonic extraction-gas chromatography-mass spectrometry-internal standard method. The samples of plant leaves were extracted with ultrasonic extraction and purified with solid-phase extraction columns. The PAHs were separated by using gas chromatography-mass spectrometry equipped with a DB-EUPAH capillary column (20 m × 0.18 mm × 0.14 μm) with a selective ion monitoring (SIM) detection mode, and quantified with an internal standard. The method had good linearity in the range of 0.005~1.0 μg/mL with correlation coefficients greater than 0.99, and the method detection limit and maximum quantitative detection limit were in the ranges of 0.2~0.7 μg/kg and 0.8~2.8 μg/kg, respectively. The method was verified with spiked recovery experiments. The average spiked recovery ranged from 71.0% to 97.6% and relative standard deviations (n = 6) were less than 14%. Herein, we established a quantitativemethod for the simultaneous determination of priority and non-priority PAHs in plant leaves using GC-MS. The method is highly sensitive and qualitatively accurate, and it is suitable for the determination of PAHs in plant leaves.