Editing Reductive dechlorination (section)

==Electrochemical==

The [[electrochemical reduction]] of chlorinated chemicals such as [[chlorinated hydrocarbons]] and chlorofluorocarbons can be carried out by [[electrolysis]] in appropriate solvents, such as mixtures of water and alcohol. Some of the key components of an electrolytic cell are types of electrodes, electrolyte mediums, and use of mediators. The [[cathode]] transfers electrons to the molecule, which decomposes to produce the corresponding hydrocarbon (hydrogen atoms substitute the original chlorine atoms) and free chloride ions. For instance, the reductive dechlorination of CFCs is complete and produces several [[Hydrofluorocarbon|hydrofluorocarbons]] (HFC) plus chloride.

Hydrodechlorination (HDC) is a type of reductive dechlorination that is useful due to its high reaction rate. It uses H<sub>2</sub> as the reducing agent over a range of potential electrode reactors and [[Catalysis|catalysts]].<ref>{{Cite journal|last1=Hoke|first1=Jeffrey B.|last2=Gramiccioni|first2=Gary A.|last3=Balko|first3=Edward N.|title=Catalytic hydrodechlorination of chlorophenols|journal=Applied Catalysis B: Environmental|volume=1|issue=4|pages=285–296|doi=10.1016/0926-3373(92)80054-4|year=1992|bibcode=1992AppCB...1..285H }}</ref> Amongst the types of catalysts studied such as [[precious metal]]s (platinum, palladium, rhodium), [[transition metal]]s (niobium and molybdenum), and [[Oxide|metal oxides]], a preference for precious metals overrides the others. As an example, palladium often adopts a lattice formation which can easily embed hydrogen gas making it more accessible to be readily oxidized.<ref>{{Cite journal|last1=Cheng|first1=I. Francis|last2=Fernando|first2=Quintus|last3=Korte|first3=Nic|date=1997-04-01|title=Electrochemical Dechlorination of 4-Chlorophenol to Phenol|journal=Environmental Science & Technology|volume=31|issue=4|pages=1074–1078|doi=10.1021/es960602b|issn=0013-936X|bibcode=1997EnST...31.1074C}}</ref> However a common issue for HDC is catalyst deactivation and regeneration. As catalysts are depleted, chlorine poisoning on surfaces can sometimes be observed, and on rare occasions, metal [[sintering]] and [[leaching (chemistry)|leaching]] occurs as a result.<ref name=":0">{{Cite journal|last=Ju|first=Xiumin|date=2005|title=Reductive Dehalogenation of Gas-phase Trichloroethylene using Heterogeneous Catalytic and Electrochemical Methods|url=http://arizona.openrepository.com/arizona/handle/10150/193594|journal=University of Arizona Campus Repository}}</ref>

Electrochemical reduction can be performed at ambient pressure and temperature.<ref>{{Cite book|title=Chemical degradation methods for wastes and pollutants: environmental and industrial applications|date=2003|publisher=M. Dekker|others=Tarr, Matthew A.|isbn=978-0-203-91255-3|location=New York|oclc=54061528}}</ref> This will not disrupt microbial environments or raise extra cost for remediation. The process of dechlorination can be highly controlled to avoid toxic chlorinated intermediates and byproducts such as [[Polychlorinated dibenzodioxins|dioxins]] from [[incineration]]. [[Trichloroethylene]] and perchloroethylene are common targets of treatment which are directly converted to environmentally benign products. Chlorinated alkenes and alkanes are converted to hydrogen chloride which is then neutralized with a base.<ref name=":0" /> However, even though there are many potential benefits to adopting this method, research have mainly been conducted in a laboratory setting with a few cases of field studies making it not yet well established.