The most common and most likely answer to this crossword clue is the 8 letter word CARBOLIC
I've seen this crossword clue in The Guardian
C
A
R
B
O
L
I
C
More clues leading to the result CARBOLIC
Buddy explains!

The straight part
We know that "Type of acid" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case type of acid = carbolic.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CARBOLIC mean?
CARBOLIC noun- Carbolic acid or similar disinfectant
- Of, relating to or containing carbolic acid