Monolithic microporous substrate for chromatographic beds
Methods and devices are disclosed for a separation device including a sintered polymeric monolith having polymeric microparticulate solids with a pore size from about 0.5 to about 8 microns, a porosity between about 50 percent to about 80 percent and a chromatographic uniformity characterized by an HETP (height equivalent of a theoretical plate) less than about 100 microns.
1 . A monolithic chromatographic microporous substrate comprising a sintered microparticulate solid forming the monolithic chromatographic substrate having an average pore diameter from about 0.5 μm to about 10 μm, a porosity of about 50 percent to about 80 percent and a thickness greater than 1.0 mm; and
wherein the monolithic microporous substrate has a compressive modulus greater than about 50 psi (0.345 MPa).
2 . The monolithic chromatographic microporous substrate of claim 1 , wherein the sintered microparticulate solid is a microparticulate powder having an average particle diameter range of about 1.0 μm to about 50 μm.
3 . The monolithic chromatographic microporous substrate of claim 2 , wherein the microparticulate powder the average particle diameter range is about 5.0 μm to about 10 μm.
4 . The monolithic chromatographic microporous substrate of claim 1 , wherein the sintered microparticulate solid comprises polymeric microfibers having an average diameter of about 0.2 μm to about 8 μm; and
wherein the monolithic microporous substrate compressive modulus is greater than about 500 psi (3.45 MPa).
5 . The monolithic chromatographic microporous substrate of claim 4 , wherein the polymeric microfibers have an average diameter of about 0.5 μm to about 4 μm; and
wherein the monolithic microporous substrate compressive modulus is greater than about 1000 psi (6.90 MPa).
6 . The monolithic chromatographic microporous substrate of claim 1 , wherein the sintered microparticulate solid is a mixture of a microparticulate powder having an average particle diameter of about 1.0 μm to 50 μm and a polymeric microfiber having an average diameter of about 0.2 μm to about 8 μm and an average aspect ratio of about 10 to about 1000; and
wherein the microparticulate powder comprises up to about 50 percent of a total solid volume of the monolithic microporous substrate.
7 . The monolithic chromatographic microporous substrate of claim 1 , wherein an average pore size is about 0.5 μm to about 3 μm and a porosity of about 55 percent to about 70 percent;
wherein the sintered microparticulate solid comprises stacked nonwoven webs of polymeric microfibers wherein the stacked nonwoven webs of polymeric microfibers have an average diameter of about 0.2 μm to about 8 μm; and
wherein the stacked nonwoven webs of polymeric microfibers are convectively sintered.
8 . The monolithic chromatographic microporous substrate of claim 1 , further comprising:
a housing wherein said monolithic microporous substrate is bonded to the housing to form a chromatographic cassette.
9 . The monolithic chromatographic microporous substrate of claim 8 , wherein the chromatographic cassette has a height equivalent of a theoretical plate (HETP) lower than about 400 μm and an asymmetry of about 0.9 to about 2 at a bed superficial velocity of about 1.0 cm/min.
10 . The monolithic chromatographic microporous substrate of claim 1 , wherein the average pore diameter is about 5 μm to about 10 μm, and the thickness is greater than 2.0 mm.
11 . The monolithic chromatographic microporous substrate of claim 1 , wherein the monolithic microporous substrate compressive modulus is greater than about 500 psi (3.45 MPa).
12 . The monolithic chromatographic microporous substrate of claim 4 wherein the sintered microparticulate solid comprises polymeric microfibers having an average diameter of about 0.8 μm to about 8 μm.
13 . The monolithic chromatographic microporous substrate of claim 5 , wherein the polymeric microfibers have an average diameter of about 1 μm to about 4 μm.
14 . The monolithic chromatographic microporous substrate of claim 7 , wherein the polymeric microfibers have an average diameter of about 0.8 μm to about 3 μm.