The writeup on this site has serious mistakes in it. By following this method you unlikely get any result. Basicallly the last step is wrong. Doing it as described you'll convert all your p2p into tar. Proper ways is to prepare 10% NaOH solution in 50/50 water/ethanol mixture. Use 500ml of this mixture per 100g of your starting material. Don't heat. Just mix 1 hour, your mixture turns orange and heats up. Mix well! After 1 hour you have to extract your product and get rid of NaOH. Othervise your p2p will be all lost on distillation no matter vacuum or not.
BTW even if done right this method gives you about 35% yeld AT BEST. From crystallized methyl-phenyl-butenone (the writeup says nothing about getting crystals on the first step).
There are also mistakes on the first step. To do it right you have to mix 1:2 mol ratio benzaldehyde:mek, cool it below 5 degrees, then add 20g of HCL gas per 100g of benzaldehyde. Not just "gas it for 1.5h".
You have to wait 2 days for this reaction to complete. Then, probably you'll get the yeld they mentoined in this writeup. Methyl-phenyl-butenone must be vacuum distilled, then crystallized.
Amount of acetic acid is enormous, you can use two times less of it.
And so on..