58802-21-4

Usage

Uses

Used in Environmental Monitoring:
3,7-dichlorodibenzo[b,d]furan is used as a marker for environmental contamination due to its presence in areas with chlorinated chemical releases, such as industrial sites and waste incinerators. Monitoring its levels helps assess the extent of pollution and the effectiveness of mitigation efforts.
Used in Toxicological Research:
3,7-dichlorodibenzo[b,d]furan is utilized as a subject in toxicological studies to understand its adverse health effects, including developmental and reproductive issues, as well as its potential carcinogenicity. This research aids in developing guidelines for exposure limits and safety measures.
Used in Waste Management and Pollution Control:
3,7-dichlorodibenzo[b,d]furan is a focus in waste management and pollution control strategies to mitigate its presence in ecosystems. Efforts to reduce its release and remediate contaminated sites involve the identification and management of 3,7-dichlorodibenzo[b,d]furan.

Upstream product

• 108-43-0 3-monochlorophenol 

Downstream Products

• 132-64-9 dibenzofuran 
• 90-43-7 2-Phenylphenol 

Relevant academic research and scientific papers

Formation of chlorinated phenols, dibenzo-p-dioxins, dibenzofurans, benzenes, benzoquinnones and perchloroethylenes from phenols in oxidative and copper (II) chloride-catalyzed thermal process

Formation of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and chlorinated phenols on CuCl2 from unsubstituted phenol and three monochlorophenols was studied in a flow reactor over a temperature range of 100-425 °C. Heated nitrogen gas streams containing 8.0% oxygen were used as carrier gas. The 0.00024 mol of unsubstituted phenol and 0.00039 mol of each monochlorophenol were passed through a 1 g and 1 cm SiO2 particle containing 0.5% (Cu by mass) CuCl2. Chlorination preferentially occurred on ortho-(2, 6) and para-(4) positions. Chlorination increased up to 200 °C, and thereafter decreased as temperature increased. Chlorination of phenols plays an important role in the formation of the more chlorinated PCDD/Fs. Chlorinated benzenes are formed possibly from both chlorination of benzene and chlorodehydroxylation of phenols. Chlorinated phenols with ortho chlorine formed PCDD products, and major PCDD products were produced via loss of one chlorine. For PCDF formation, at least one unchlorinated ortho carbon was required.

Identification of surrogate compounds for the emission of PCDD/F (I-TEQ value) and evaluation of their on-line realtime detectability in flue gases of waste incineration plants by REMPI-TOFMS mass spectrometry

Correlations between products of incomplete combustion (PIC), e.g., chloroaromatic compounds, can be used to characterise the emissions from combustion processes, like municipal or hazardous waste incineration. A possible application of such relationships may be the on-line real-time monitoring of a characteristic surrogate, e.g., with Resonance-Enhanced Multiphoton Ionization-Time-of-Flight Mass Spectrometry (REMPI-TOFMS). In this paper, we report the relationships of homologues and individual congeners of chlorinated benzenes (PCBz), dibenzo-p-dioxins (PCDD), dibenzofurans (PCDF) and phenols (PCPh) to the International Toxicity Equivalent (I-TEQ) of the PCDD/F (I-TEQ value) in the flue gas and stack gas of a 22 MW hazardous waste incinerator (HWI). As the REMPI detection sensitivity is decreasing with the increase of the degree of chlorination, this study focuses on the lower chlorinated species of the compounds mentioned above. Lower chlorinated species, e.g., chlorobenzene (MCBz), 1,4-dichlorobenzene, 2,4,6-trichlorodibenzofuran or 2,4-dichlorophenol, were identified as I-TEQ surrogates in the flue gas. In contrast to the higher chlorinated phenols, the lower chlorinated phenols (degree of chlorination 4) were not reliable as surrogates in the stack gas. The identified surrogates are evaluated in terms of their detectability by REMPI-TOFMS laser mass spectrometry. The outcome is that MCBz is the best suited surrogate for (indirect) on-line measuring of the I-TEQ value in the flue gas by REMPI-TOFMS. The correlation coefficient r of the MCBz concentration to the I-TEQ in the flue gas was 0.85.

Temperature dependence of DCDD/F isomer distributions from chlorophenol precursors

The temperature dependence of the gas-phase, rate-limited formation of dichlorodibenzo-p-dioxin (DCDD) and dichlorodibenzofuran (DCDF) isomers from 2,6-dichlorophenol and 3-chlorophenol, respectively, has been studied experimentally in an isothermal flow reactor over the range 300-900°C under pyrolytic, oxidative and catalytic conditions and computationally using semi-empirical molecular orbital methods. At high temperatures, distributions of sets of DCDD/F condensation products are consistent with the calculated thermodynamic distributions, indicating that the relative rates of formation are governed by differences in symmetry and steric hindrance present in the isomer product structures. At low temperatures, however, this is not the case. In the case of 1,6- and 1,9-DCDD formed from 2, 6-dichlorophenol via Smiles rearrangement, the 1,6 isomer is favored at low temperatures more than thermodynamically predicted. This result appears to be consistent with kinetic effects of either the expansion of the five-membered ring Smiles intermediate or a lower activation energy six-membered ring intermediate pathway that produces only the 1,6 isomer. For formation of 1,7-, 3,7- and 1,9-DCDF from 3-chlorophenol, the 1,7 isomer fraction increases at low temperatures whereas thermodynamics predicts a decrease. This result can be attributed to steric effects in alternative sandwich-type approach geometries of phenoxy radicals to form the o, o′-dihydroxybiphenyl (DOHB) intermediate via its keto-tautomers. Higher level molecular theory (ab initio) is needed to provide a more quantitative description of these kinetics.