Is this your John Banks?
1841
Chester Buildings
Crown Court belper Derbys
John Banks 35 Cotton factory Smith
Elizabeth 35
Benjamin 13
John 10
Elizabeth 4
Herbert 3mths
all b in county
HO107 180 4 4 19
1851 living in lancs
children with them are Ann 20, Elizabeth 14, herbert 11, hannah 7, Sarah mths?
John and Elizabeth and children all b Belper (except Sarah who was b manchester
HO107 226 174 49
With the age gap in children in 1841 it looks as if John cold have been married previously
but
IGI has (extracted records)
the following baptisms:
all in Belper Derbys
all to parents John Banks and Elizabeth
Ann Banks 20 Jun 1830
John Banks 1832
Benjamin Banks 4 april 1828
so either John and Elizabeth married pre 1828 -or John married 2 elizabeths?

Suz