About: http://webisa.webdatacommons.org/198022917

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	During the recycling process, contaminants such as emulsified oils and heavy metals must be removed either by filtration, distillation, reverse osmosis, or ion exchange.
http://www.w3.org/ns/prov#wasQuotedFrom	cedmag.com