To make a non-polar solvent less polar, you can employ several methods. Here are a few commonly used techniques:
Dilution: Mixing a non-polar solvent with a larger volume of another non-polar solvent can effectively reduce its overall polarity. By diluting the non-polar solvent with a non-polar counterpart, you decrease the relative concentration of polar molecules or impurities present, thereby lowering its overall polarity.
Temperature Reduction: In some cases, lowering the temperature of a non-polar solvent can reduce its polarity. Cooling the solvent can cause a decrease in the thermal energy of the molecules, leading to a reduction in their motion. This reduction in molecular motion can result in weaker intermolecular forces, including dipole-dipole interactions, which contribute to the overall polarity of the solvent.
Selective Adsorption: Another approach is to utilize adsorbent materials that have a higher affinity for polar molecules. For example, activated charcoal or certain molecular sieves can selectively adsorb polar impurities or molecules from the non-polar solvent. By passing the non-polar solvent through such adsorbents, you can effectively reduce its polarity by removing polar contaminants.
Distillation or Fractional Distillation: Distillation is a technique that can be employed to separate different components in a mixture based on their boiling points. Fractional distillation, a more precise variant, can be utilized when dealing with closely boiling compounds. By subjecting the non-polar solvent to distillation or fractional distillation, you can potentially separate or remove more polar components, thus reducing its overall polarity.
It's important to note that the effectiveness of these methods can vary depending on the specific non-polar solvent, its initial polarity, and the desired level of polarity reduction. Additionally, it's crucial to consider the compatibility and potential reactions between the non-polar solvent and any solvents, adsorbents, or conditions employed during the process.