Police say Delfino Mora was attacked in an alley on the city's North Side early Tuesday. A passer-by found him hours later, bleeding and unconscious, and he was taken to St. Francis Hospital in Evanston in critical condition.
The Cook County medical examiner's office said Mora died Wednesday afternoon from blunt head trauma.
The teens were arrested over the weekend and are slated to appear in court Monday.
Mora's family said the father of 12 was disabled because of a workplace injury and was in the alley collecting aluminum cans to earn money for his family.
"Every day he would like take his truck and go in the alleys looking for cans or for any other metal," said Angelica Mora, one of Mora's daughters.
His family said Mora had just saved enough money to buy a suit to wear to his son's wedding next month.
Police said the teens being held in the killing are gang members who took turns using a cell phone to record the beating after demanding money from Mora.