Transport and release of electron donors and alkalinity during reductive dechlorination by combined emulsified vegetable oil and colloidal Mg(OH) 2 : Laboratory sand column and microcosm tests

摘要: Abstract Emulsified vegetable oil combined with colloidal Mg(OH)2 (EVO-CM) can slowly release electron donors and OH– into groundwater is therefore regarded as a promising amendment for enhanced in situ treatment of chlorinated solvents, such tetrachloroethene (PCE) trichloroethene (TCE). However, its migration ability different porous media the simultaneous donor pH buffer during reductive dechlorination (ERD) have never been evaluated detail. In this study, EVO-CM uniform drop size desirable stability was prepared. Laboratory-scale column tests were conducted to investigate transport spatial distribution media. Batch microcosm experiments carried out study efficiency under EVO:Mg(OH)2 ratios. Experimental results indicate that prepared emulsions be transported effectively through grain ranging from 0.1–1.0 mm. The emulsified (EVO) showed synchronous movement systems, providing both alkalinity at same location. retention degree greater finer grained decreases increasing distance inlet. injection lead significant mobilization TCE column. microcosms remarkably presence EVO-CM. coaddition sufficient limits deleterious decline caused by acid release. achieves an optimum when ratio 1:1.