Chlorine and Chlorinated Compounds Removal from Industrial Wastewater Discharges: A Review

Adsorption techniques for industrial wastewater treatment rich in heavy metals and aqueous solutions of water-soluble such as Cl−, F−, HCO3−, NO3−, SO2−4, and PO3−, often include technologies for toxicity removals. The recent advancement and technical applicability in the treatment of chlorine and chlorinated compounds from industrial wastewater are reviewed in this article. Chlorine and chlorinated compounds are among the common discharged constituents from numerous industries. They can be carcinogenic or naturally toxic and can pose issues to aquatic ecosystems and human beings. Thus, elimination of chlorides and chlorinated compounds from water or wastewater is inevitable to get rid of the problem. Several techniques are being applied for the reduction of chlorine and chlorinated compounds in water. These include biodegradation, photochemical, adsorption, chemical, electrochemical, photo-electrochemical, membrane, supercritical extraction and catalytic method. Chlorine can react with various organic and inorganic micro-pollutants. However, the potential reactivity of chlorine for specific compounds is small, and only minor variations in the structure of the parent compound are anticipated in the water treatment process under typical conditions. This paper reviews different techniques and aspects related to chlorine removal, the types of chlorine species in solution and their catalyst, chlorine fate and transport into the environment, electrochemical techniques for de-chlorination of water, kinetics, mechanisms of reduction of chlorinated compounds, and kinetics of the electrochemical reaction of chlorine compounds. Keywords: Industrial waste, Kinetics, Wastewater, Water purification

Chlorinated metabolites with antibacterial activities from a deep-sea-derived Spiromastix fungus

Chromatographic separation of the solid cultures of a deep-sea-derived Spiromastix fungus (MCCC 3A00308) resulted in the isolation of five chlorinated compounds with antibacterial activities.

The Study on Chlorination by Sulfuryl Chloride of Benzene/Pyridine Carboxamides and Carbonitriles

In the chlorination of N-[2-aryl-1-(1-piperidinylcarbonyl)ethenyl]arenecarboxamides, it has been found that a derivative having two methoxy substituents on the arenecarbonyl ring undergoes chlorination on the same ring rather than converting into the expected enamine bond chlorination product. Based on the above results, the chlorination of benzamides/nicotinamides by sulfuryl chloride (SO2Cl2) has been studied. We developed a method of synthesizing aromatic chlorinated compounds by treating aromatic amides or nitriles with SO2Cl2 in dichloromethane at 0oC without catalyst. This is a new mild method and gives good yields, especially when benzene ring is substituted by amide or cyano group together with the alkoxy group.

Chloroanisoles and Other Chlorinated Compounds in Cork from Different Geographical Areas

Cork quality is crucial for the fabrication of corks intended to be used to seal wine bottles. This work has focused on the determination of chloroanisoles (CAs)—exogenous compounds with a low perception threshold—in cork. The identification and quantification of these compounds was carried out with Bond Elut-ENV solid phase extraction and gas chromatography with mass spectrometry detection. Cork samples were obtained from oaks from Catalonia, Extremadura and Italy, and the presence of CAs was evaluated. Moreover, cork affected by the presence of yellow stains (a defect present in cork, mainly originated from the growth of the fungus Armillaria mellea) was analysed separately. The results obtained from cork macerates revealed the presence of trichloroanisole (TCA) in Catalan and Italian cork. Furthermore, TCA concentration was not statistically different when comparing cork affected and non-affected by the growth of A. mellea. Other chlorinated compounds were identified by comparison of their mass spectra with the data from the NIST library.