Poplar wood was fractionated under a range of conditions using an inexpensive and recyclable commercial aromatic acid, p-toluenesulfonic acid (p-TsOH), as an acid hydrotrope (AH). The fractionated cellulose-rich solid fraction demonstrated excellent physical and optical properties as papermaking fibers. The dissolved xylose can be dehydrated into furfural using the p-TsOH in the spent liquor without additional catalysts. The acid hydrotrope dissolved lignin (AHL) has high beta-aryl ether linkage content (similar to 60%) and high molecular weight (similar to 4000 Da), similar to that of mill wood lignin (MWL). Increasing acid hydrotrope fractionation (AFIF) severity increased AHL yield, but reduced beta-aryl ether bonds, decreased molecular weight and increased AHL glass transition temperature. An AHL yield of 50% can be obtained while retaining approximately half of the beta-O-4 linkages, beneficial for lignin valorization as a polymer in composites as well as for production of monomers or aromatics through subsequent depolymerization.