The phrase "a great deal of time in" is grammatically correct and can be used in written English. It is typically used to describe the amount of time spent doing a particular activity or in a certain place. Example: "I have spent a great deal of time in the library this semester studying for my exams."
Adelson began spending a great deal of time in Israel.
Their father "spent a great deal of time in Africa and a great deal of time in east Asia.
A great deal of time in our curriculum is focused on optimizing communication with future patients.
He spent a great deal of time in the mountains around Jackson Hole, Wyoming.
It later spent a great deal of time in a collection in Washington State.
I've spent a great deal of time in the Middle East.
Millions of children today spend a great deal of time in early education (child-care) settings.
Adelson was still living in Boston, but he and Miriam began spending a great deal of time in Las Vegas.
"This requires, obviously, that I should spend a great deal of time in London," she acknowledged in the same essay.
Also he spent a great deal of time in London, and I did not want to do that".
Q. You've said you spent a great deal of time in California rather than focusing on swing states.
Ludwig does not simply clarify my doubts with English writing, it enlightens my writing with new possibilities
Simone Ivan Conte
Software Engineer at Adobe, UK