そんな itself means "such" when it's used before a noun or to refer to the amount you are seeing when used as そんなに.
So, yes, it can be used as an expression of disbelief.

Some examples:

> そんなに食べるの？？？ 

Are you going to eat that much??? (You see lots of food in　front of the person and you can't believe that the person is trying to each that amount of food.)



> こんなに食べたの？？？ 

Did you eat all of them??? (You can lots of empty plates　in front of the person and you can't believe that the person ate all of it.)

>そんな（ばかな／きたいない）ことしないで

Don't do such a (stupid/dirty) thing

>そんな（ばかな／つめたい／ひどい）こと言わないで

Don't say such a (stupid/cold/cruel) thing



So, taking @NothingAtAll's advice...
You may hear people say `そんな。。。`, which has the nuance of disbelief because you are just not repeating or describing the details (ellipsis of the above examples), and it kind of means like `Oh no...` by itself

Examples:

> A: You are the worst student I've ever had 
>
> B: そんな。。。　（そんなひどいこと言うのね。。。）
> 

or 

> A: You are now allowed to join the party! 
>
> B: そんな。。。(そんなひどいことを私にするのね。。。）