For high quality syrups, a simple one-stage filtration step will often suffice to produce the required standard. Usually this can be achieved using an all-cellulose depth filter sheet.
In some unrefined syrups however, there may also be a significant level of impurities and finished drink quality requirements will demand their selective removal, possibly combined with decolourisation of the syrup. Traditional decolourising/ICUMSA reduction treatment in such circumstances often involves the use of powdered activated carbon. One feature of this method is that, in additional to the particulate impurity, the activated carbon has also to be removed often using a support sheet pre-coated with kieselguhr in a filter press.
Your best best would be to contact a filter company directly so they can discuss with you the exact application you need and what the requirements are. It really depends on syrup temperature, dilution of syrup etc.. as to what filter to incorporate. I think Carlson are a pretty well renown company that can help you in this matter. Just do a google search for Carlson Filtration.