After moving to New York City, Khalil became an expert in printmaking and later opened a studio where his clients included Norman Lewis, Louise Nevelson, and Sean Scully. He began teaching at Pratt Institute in 1973, the first of many schools where he has taught in the US. Khalil's works gained in popularity, especially in North America and Europe. His first solo exhibition took place in 1979. This was followed by decades of success and exhibitions in Africa, Asia, Europe, and North America.
Khalil's travels throughout the Arab world and his time spent in Italy and New York City have greatly influenced his works.[5] It was in Morocco where his first solo exhibition took place in 1979 at the Galerie Basamat in Casablanca. This was followed by solo exhibitions at The New School in 1981, and New York City's Limited Art Editions in 1984. That same year he was part of group exhibitions at the El Paso Museum of Art, Tacoma Art Museum, Washington Seventh Norwegian Print Biennial, and the African American Museum in Dallas.[4]
Khalil is a fan of Bob Dylan's music and in 1986, created a seven-part series of etchings with aquatint prints inspired by Dylan's music.[2][7] Describing the inspiration for these pieces, Khalil said "I listened to Dylan every day...at a point in my life [when] there was an empathy with the sadness and anger in Dylan's life and music."[8] One of these prints, Tangled Up in Blue, was later purchased by the National Museum of African Art in Washington, D.C.[8] Although the series was inspired by Dylan, they show scenes in Sudan, including one of Suakin.[7]
Another series in 1989-1990 was inspired by Petra. Responding to these etchings, Sylvia Williams wrote: "When asked about the caves, [Khalil] commented that he wanted to convey the mystery and ambiguity of suggesting whether one is looking into darkness or looking out into light. Kahlil often speaks of light and dark as a series of positive and negative effects that he wants to capture. It seems to sum up not only his pictorial vocabulary but also his philosophy of life."[2]
A major exhibition took place in 1994-1995 at the National Museum of African Art where Khalil's works, sculptures by Amir Nour, and "book art" by Atta Kwami were displayed. Describing Khalil's work in The Washington Post, a reporter wrote Khalil's artistic style "equally embraces America's Bob Dylan and Jordan's ruined Petra."[7] Writing in the Nka Journal of Contemporary African Art, Robert Condon said Khalil and Nour's works "challenges all perceived notions of what abstraction connotes" and noted Khalil uses photographs on his etchings to give the appearance of paintings.[9]
His solo exhibitions in the 2000s took place at the Rochan Gallery in Jeddah, the Skoto Gallery, the Hassan II Centre for International Encounters in Asilah, and the Albareh Art Gallery. This was followed by a group exhibition in 2010 at the Mathaf: Arab Museum of Modern Art in Doha, and solo exhibitions at the Albareh Art Gallery, the Meem Gallery in Dubai, and the Aicon Gallery in New York City during the 2010s.[4] Khalil was awarded the 2019 Nile Award for Arab Innovators by Egypt's Supreme Council for Culture.[10]