To fix the illegal quoting issue, use a quote\_char that is not in your data:
```ruby
CSV.open('data.csv', quote_char: "\x00", col_sep: "\t").each do |s|
end
```
Use double quotes around \\x00, otherwise you'll get:
```ruby
:quote_char has to be a single character String
```
You can also try the "liberal_quoting" option available in Ruby 2.4, and specifying the correct quote_char...