If the seeds don’t shake loose from the peppers, try chopping them on a cutting board. You can get a lot of the seeds to stay behind by scraping your knife at a cross-wise angle across the chopped peppers. If that doesn’t take out enough of the hot seeds, then make a paste with the chopped sichuan peppers by adding a little vinegar or broth. Add just enough liquid to get the peppers into solution so you can then decant the peppery liquid into another dish. The seeds should remain (mostly) on the bottom of the liquid preparation and therefore be left behind.

Those are the steps I’d try, but we like the hot seeds in the food and don’t fuss with taking them out. To each their own, right?

Have fun and good eats!

Extracting properties from plant materials can be accomplished with all the solvents you mentioned (Vodka or 35% alcohol or glycerin) and the choice may depend on what is available to you most readily. The higher strength alcohol works better than 35% alcohol for extracting purposes. Once the essence is extracted with pure alcohol it can be diluted to 35% for use.

Alcohol is much more widely available in my location, so that is what I would use for extractions instead of glycerin.
Good luck and let us know how it works for you!

with regards Raj

Have you tried drying it in a microwave? If the plant material can be pressed between some paper with a few layers of thin cardboard, it might work. It could be dried quickly in the microwave and perhaps save the green color.

Give it a try and let us know how it works!