make pure vs improve

make pure and improve both are verbs.

Word	Noun	Adjective	Verb	Adverb
make pure	No	No	Yes	No
improve	No	No	Yes	No

As verbs, improve is a hypernym of make pure; that is, improve is a word with a broader meaning than make pure:

make pure: remove impurities from, increase the concentration of, and separate through the process of distillation
improve: to make better

Other hypernyms of make pure include ameliorate, amend, better, meliorate.

make pure (verb)	improve (verb)
remove impurities from, increase the concentration of, and separate through the process of distillation	get better
	to make better