def filter_ionic_liquids(data_set):
    """Filters out ionic liquids.

    Parameters
    ----------
    data_set: pandas.DataFrame
        The data set to filter

    Returns
    -------
    pandas.DataFrame
        The filtered data set.
    """

    def filter_function(data_row):

        n_components = data_row["N Components"]

        for index in range(n_components):

            smiles = data_row[f"Component {index + 1}"]

            if "." in smiles:
                return False

        return True

    return data_set[data_set.apply(filter_function, axis=1)]