Abstract: An apparatus for efficiently removing the exuded substance and/or the attached substance on the surface of a catalyst (catalyst surface substance) from the catalyst is provided. The apparatus comprising a main body, the apparatus for removing a catalyst surface substance present on a surface of a catalyst from the catalyst by bringing a gas flow into contact with the catalyst housed in the main body, wherein a gas flow length in a flow direction of the gas flow is 55 mm or more, and an average flow velocity of the gas flow is 80 m/s or more and 500 m/s or less in terms of a linear velocity at 15° C. and 1 atm.

Abstract: Disclosed is a calcination apparatus, including: a calcination tube having open ends at both terminals; a pair of hoods, each hood covering each open end of the calcination tube; and a pair of rings, each ring sealing a gap between the calcination tube and the hood, wherein the rings are directly or indirectly fixed on an outer surface of the calcination tube; a groove is provided along a circumferential direction of the ring at a contact surface side between the ring and the hood; a sealed chamber surrounded by the hood and the groove is formed; and both the calcination tube and the rings rotate in a circumferential direction of the calcination tube while keeping the hood in contact with both sides of the groove.

Abstract: Disclosed is a calcination apparatus, including: a calcination tube having open ends at both terminals; a pair of hoods, each hood covering each open end of the calcination tube; and a pair of rings, each ring sealing a gap between the calcination tube and the hood, wherein the rings are directly or indirectly fixed on an outer surface of the calcination tube; a groove is provided along a circumferential direction of the ring at a contact surface side between the ring and the hood; a sealed chamber surrounded by the hood and the groove is formed; and both the calcination tube and the rings rotate in a circumferential direction of the calcination tube while keeping the hood in contact with both sides of the groove.

Abstract: Disclosed is a calcination apparatus, including: a calcination tube having open ends at both terminals; a pair of hoods, each hood covering each open end of the calcination tube; and a pair of rings, each ring sealing a gap between the calcination tube and the hood, wherein the rings are directly or indirectly fixed on an outer surface of the calcination tube; a groove is provided along a circumferential direction of the ring at a contact surface side between the ring and the hood; a sealed chamber surrounded by the hood and the groove is formed; and both the calcination tube and the rings rotate in a circumferential direction of the calcination tube while keeping the hood in contact with both sides of the groove.

Abstract: Disclosed is a calcination apparatus, including: a calcination tube having open ends at both terminals; a pair of hoods, each hood covering each open end of the calcination tube; and a pair of rings, each ring sealing a gap between the calcination tube and the hood, wherein the rings are directly or indirectly fixed on an outer surface of the calcination tube; a groove is provided along a circumferential direction of the ring at a contact surface side between the ring and the hood; a sealed chamber surrounded by the hood and the groove is formed; and both the calcination tube and the rings rotate in a circumferential direction of the calcination tube while keeping the hood in contact with both sides of the groove.

Abstract: An apparatus for efficiently removing the exuded substance and/or the attached substance on the surface of a catalyst (catalyst surface substance) from the catalyst is provided. The apparatus comprising a main body, the apparatus for removing a catalyst surface substance present on a surface of a catalyst from the catalyst by bringing a gas flow into contact with the catalyst housed in the main body, wherein a gas flow length in a flow direction of the gas flow is 55 mm or more, and an average flow velocity of the gas flow is 80 m/s or more and 500 m/s or less in terms of a linear velocity at 15° C. and 1 atm.

Abstract: Disclosed is an oxytetramethylene glycol copolymer, which is obtained by copolymerizing tetrahydrofuran and neopentyl glycol and which has a specific number average molecular weight Mn, a specific molecular weight distribution Mw/Mn, a specific neopentyl glycol copolymerization whole ratio Nw and a specific neopentyl glycol copolymerization partial ratio Nh, and a method for producing the same. Also disclosed is a method for purifying an oxytetramethylene glycol copolymer, which comprises adding a fresh tetrahydrofuran to a reaction mixture comprising an oxytetramethylene glycol copolymer and an unreacted diol, wherein the amount of added tetrahydrofuran is not less than the weight of the unreacted diol contained in the reaction mixture, and distilling off the unreacted diol together with the added tetrahydrofuran.

Abstract: Disclosed is an oxytetramethylene glycol copolymer, which is obtained by copolymerizing tetrahydrofuran and neopentyl glycol and which has a specific number average molecular weight. Mn, a specific molecular weight distribution Mn/Mw, a specific neopentyl glycol copolymerization whole ratio Nw and a specific neopentyl glycol copolymerization partial ratio Nh, and a method for producing the same. Also disclosed is a method for purifying an oxytetramethylene glycol copolymer, which comprises adding a fresh tetrahydrofuran to a reaction mixture comprising an oxytetramethylene glycol copolymer and an unreacted diol, wherein the amount of added tetrahydrofuran is not less than the weight of the unreacted diol contained in the reaction mixture, and distilling off the unreacted diol together with the added tetrahydrofuran.

Abstract: An oxytetramethylene glycol copolymer obtained by copolymerizing tetrahydrofuran and neopentyl glycol which has a specific number average molecular weight Mn, a specific molecular weight distribution Mw/Mn, a specific neopentyl glycol copolymerization whole ratio Nw and a specific neopentyl glycol copolymerization partial ratio Nh; a method for producing the same; and a method for purifying an oxytetramethylene glycol copolymer using fresh tetrahydrofuran.

Abstract: Disclosed is an oxytetramethylene glycol copolymer, which is obtained by copolymerizing tetrahydrofuran and neopentyl glycol and which has a specific number average molecular weight Mn, a specific molecular weight distribution Mn/Mw, a specific neopentyl glycol copolymerization whole ratio Nw and a specific neopentyl glycol copolymerization partial ratio Nh, and a method for producing the same. Also disclosed is a method for purifying an oxytetramethylene glycol copolymer, which comprises adding a fresh tetrahydrofuran to a reaction mixture comprising an oxytetramethylene glycol copolymer and an unreacted diol, wherein the amount of added tetrahydrofuran is not less than the weight of the unreacted diol contained in the reaction mixture, and distilling off the unreacted diol together with the added tetrahydrofuran.