TiO2 modified basalt fiber cloth with superhydrophilicity and underwater superoleophobicity for oil-water separation

Abstract

Titanium mesh, stainless steel mesh and other substrate materials for oil-water separation membranes have excellent acid and alkali resistance. However, the preparation process pollutes the environment and is costly. Therefore there is an urgent need for an economical and eco-friendly new material to replace them. Here, this research found that eco-friendly basalt fibers can replace them. In this work, superhydrophilic/underwater superoleophobic TiO2/basalt fiber cloths were prepared by solvothermal method. It has a contact angle of 0° for water in air and maximum 161° for n-hexadecane underwater. The oil-water separation efficiency was up to 99.75%, which indicated its efficient oil-water separation capability. The underwater n-hexadecane contact angle was 154° after immersing it in 6mol of HCl and NaOH for 2h respectively. This indicates that it has excellent acid and alkali resistance. And with titanium mesh, stainless steel mesh separation membrane acid and alkali resistance is not much different. However, the price is only one percent of titanium mesh. In addition, the softness of basalt fiber can be folded to enhance the pressure-bearing capacity. Therefore, this work provides a green, acid and alkali resistant, inexpensive new material for oil-water separation membranes, which has great potential in the field of oil-water separation.