This company claims that their technology will allow you to easily convert veggie oil into biofuel for about $0.46 per gallon. Basically you add the proper additives and pump the batch through a filter into your vehicle.
I did a google on DSE and found out this stuff is snake oil and the company is targeting people new to biofuels with heavy marketing and false claims.
DSE additive Material Safety Data Sheet
General
Synonyms: dimethylbenzene, xylol
Molecular formula: C6H4(CH3)2 This is a mixture of the three xylenes, m-xylene (CAS 108-38-3), o-xylene (CAS 95-47-6) and p-xylene (CAS
106-42-3), and often also contains ethyl bezene (CAS 100-41-4)."