Abstract: Polyester scrap such as film (plain or silver-bearing), fabric, yarn or bottles, based primarily on polyethylene terephthalate, is depolymerized at room temperature and atmospheric pressure with a mixture of concentrated sulfuric acid and water to form crude terephthalic acid which is purified by dissolving in alkali solution, filtering to remove impurities, acidifying the filtrate to recover terephthalic acid in high yield with a purity of at least 99%.

Abstract: Process for polymerizing 2-pyrrolidone in high yield to produce a high molecular weight polymer having the advantageous physical properties of synthetic polymers, such as strength and wear-resistance, and the advantageous chemical properties of cotton, such as water-absorptivity and release, dye-receptivity and similar ironing capability. The process is a hydrogen transfer which is catalyzed by an anion and bone dry carbon dioxide, nitrogen dioxide or sulphur dioxide gas and pushed to high yield with drying agents. Pure anhydrous 2-pyrrolidone is first reacted with an analytical grade alkali metal or its hydroxide or bicarbonate as an anion source to form a mixture comprising 2-pyrrolidone and the metal salt of 2-pyrrolidone; the mixture is then treated with the bond dry CO.sub.2, NO.sub.2 or SO.sub.

Abstract: Commercially efficient process for purifying commercial 2-pyrrolidone into substantially pure anhydrous 2-pyrrolidone comprises treating liquid impure 2-pyrrolidone with a minor amount of a solid substantially anhydrous metal hydroxide and flash vaporizing from a heated surface under closely controlled temperature and pressure conditions in a molecular distillation apparatus, without establishing a vapor pressure equilibrium. Very dark colored commercial 2-pyrrolidone may be given a preliminary purification treatment by cooling until the 2-pyrrolidone solidifies and draining off the dark-colored liquid containing impurities.