Diatomaceous earths are used for acid filtration, however after few time the pores will be clogged by sulfur. We search minerallurgical techniques in order to reuse Diatomaceous earths.
You can wash the material with CS2 (Carbon Disulfide) which is inert to other materials but dissolves out Sulphur. That will remove Sulphur as impurity from your parent material.
You can try out some organic solvents that can dissolve sulphur like Benzene and Toluene. These are less toxic but will be required more in amount. Sulphur is readily soluble in CS2 but is comparatively less soluble in Benzene and Toluene. Nevertheless, you can dissolve out Sulphur in Benzene and Toluene. For the concentration, you need to perform volumetric (molar) calculation. It depends on the strength of the CS2 solution (whether the solvent is diluted with water or used raw) and accordingly you need to calculate the volume of solution required to dissolve the Sulphur based on the amount of Sulphur content in your material.