Tentatively, those names do look rather Spanish, but that need not mean much. However, Wikipedia's page on Spanish naming conventions notes that:
Currently in Spain, people bear a single or composite given name (nombre) and two surnames (apellidos).
Traditionally, a person's first surname is the father's first surname (apellido paterno), and the second one is the mother's first surname (apellido materno).
Each surname can also be composite, the parts usually linked by the conjunction y or e (and), by the preposition de (of) or by a hyphen.
Can "i" be a variant of the "y" conjunction? The Wiki section on Catalan names suggests that it can. In addition, there is a book "The Phonology of Catalan" by Max Wheeler, available on Google Books, which states:
Within Spain, people officially have two surnames, of which the first is one's father's first surname and the second is one's mother's first surname. Some Catalan writers regularly publish using both surnames, often linked with i 'and'. One linguist who does so is Antoni M. Badia i Margarit.
So it does appear that Forename Surname1 i Surname2 is a Catalan variant of typical Spanish naming customs. Rather than "first last i something", then, the forenames of the husband and wife are Jordi and Antonia respectively, and their pairs of surnames are conjoined by the "i".
Rosa, the daughter of Jordi Flos i Margalef and Antonia Bassols i Sunyol would be expected to have the full name Rosa Flos i Bassols, but in the links in the question it appears that the maternal surname part was not included. Rosa Flos' husband's immediate family don't have the maternal part either. This may be a common convention or omission.
A brief search suggests that "Margalef" is a surname of a current Catalan politician and "Sunyol" is listed in "Surnames and Migrations: The Barcelona Area (1451-1900)" by Jordà, Pujadas-Mora and Cabré (pdf link), Barcelona being the major city in Catalonia.
Based on this, it looks like this part of your family was of Catalan descent, but it's not possible to tell from the information given whether they actually lived in Catalonia.
You're likely to get more reliable information from someone with actual expertise in Catalan language, customs and people, of course, so you may wish to investigate that avenue further.