Synthetic Alcohol is not najis
In the Name of Allah, Most Gracious, Most Merciful
In the Name of Allah, the Beneficent, the Merciful, and all blessings and peace upon our master Muhammad, his Folk, Companions and those who follow their noble way,
According to the Indian Hanafi scholars, the fatwa in our times is that synthetic alcohols (and all alcohol not considered 'khamr') is tahir, and permitted to use and consume AS LONG AS:
(a) it is not used as an intoxicant;
(b) it is not used as intoxicants as used (i.e. for alcoholic consumption, even a little);
(c) it is not used in an amount that intoxicates;
(d) it is not used in vain (lahw).
This was Mufti Mahmoud Ashraf Usmani's explanation, and it is supported by many fatwas in the great Indian Hanafi fatwa references of the 20th Century. This is the position of Imam Abu Hanifa himself. Later scholars said that the fatwa was on the position of Imam Muhammad ibn al-Hasan al-Shaybani, Abu Hanifa's student, that all alcohol is najis and haram, even in small quantities, because of widespread fitna. In our times, because of the widespread use of alcohol in all sorts of things, it has become very difficult to avoid. This is why great Hanafis of our times gave the abovementioned fatwa.