摘要:
A process for recovering heavy metal ions or heavy metal ions and halogen values from a solution comprising a lower aliphatic monocarboxylic acid, which comprises the steps of:(1) contacting a lower aliphatic carboxylic acid solution containing heavy metal ions or heavy metal ions and halogen values with an anion exchange resin, at least 60% of the ion-exchange groups of said anion exchange resin being in the bromide or chloride state, while the water concentration in the lower aliphatic monocarboxylic acid solution has been adjusted to a level lower than 20% by weight, thereby to adsorb the heavy metal ions or the heavy metal ions and the halogen values on the anion exchange resin; and(2) desorbing the adsorbed heavy metal ions or the adsorbed heavy metal ions and the adsorbed halogen values from the anion exchange resin by elution with an eluent. In the present invention, the halogen values remaining in the lower aliphatic monocarboxylic acid solution which has been contacted with the anion exchange resin can be further recovered by contacting the solution with another anion exchange resin or subjecting the solution to distillation.
摘要:
An improved process for the production of a high purity terephthalic acid by a liquid phase oxidation reaction of para-xylene by means of molecular oxygen or a molecular oxygen-containing gas in an aliphatic monocarboxylic acid solvent in the presence of a cobalt-manganese-bromine catalyst system, characterized in that as the cobalt-manganese-bromine catalyst system there is used a catalyst system of a specific composition at a specific concentration, and the liquid phase oxidation reaction is effected in the presence of acetaldehyde in addition to the cobalt-manganese-bromine catalyst system under relatively mild temperature (170.degree.-190.degree. C.) and pressure conditions while maintaining the water concentration in the reaction system at a specified low level. The terephthalic acid produced according to the process of the present invention is of so high a quality that it can be used for the direct production of a polyalkylene terephthalate from the acid and an alkylene glycol or ethylene oxide, which direct production does not need the preparation of an intermediate such as a methyl ester of terephthalic acid.
摘要:
A mixture containing formaldehyde and water is separated effectively by contacting with adsorbents of specific type A zeolites containing exchanged cations of the elements from Group IA (4) to (6) or Group IIA (6) or mixture thereof of the Periodic Table of Elements.
摘要:
A mixture containing formaldehyde and water is separated effectively by contacting with adsorbents of specific type A zeolites containing exchanged cations of the elements from Group IA (4) to (6) or Group IIA (6) or mixture thereof of the Periodic Table of Elements.
摘要:
A hydrocarbon mixture is fed to a system of adsorbents in a plug flow so as to form at least one displacement boundary in the system to accumulate the composition in the vicinity of the boundary. The process is simple to operate and suitable for separation of a hydrocarbon mixture containing components with similar physical and chemical properties such as a mixture of hydrocarbon isomers.
摘要:
A process for the separation of one rare earth metal from another in a mixture of rare earth metals by chromatographic displacement using a complexing agent and a cation exchanger, which process comprises using a cation exchanger having a micro-void volume void ratio of 0.5 to 0.95, preferably 0.5 to 0.88.
摘要:
An isotope separation apparatus comprises a plurality of independent developing units, each comprising 2 to 20 adsorbent-packed columns forming a continuous developing circuit or passageway, and the developing units are connected to at least one common main pipe for supplying an isotope mixture solution, a regenerating agent solution, or an eluent solution. Also, in a further embodiment the developing units are connected to common liquid-discharge main pipes.The separation or concentration of isotopes such as uranium isotopes, nitrogen isotopes, boron isotopes, etc., is performed by continuously developing the isotope mixture solution passed through the individual adsorbent-packed columns successively in each developing units.
摘要:
A novel protein adsorbent consisting essentially of a porous copolymer obtained by copolymerizing a monomer mixture comprising at least one cyano group-containing monomer and at least one cross-linkable monomer, said copolymer having an average pore diameter (d) of from 40 A to 9,000 A and a total pore volume of from 0.05.sqroot.X ml to 1.5.sqroot.X ml per gram of the copolymer in a dry state, in which X designates the weight proportion of said cross-linkable monomer expressed in terms of the percent by weight based on the total monomers. The present porous copolymer adsorbent has a remarkably high protein adsorbing capacity. The adorbent can advantageously be used for various purposes such as purification and separation of proteins, and removal of proteins. Copolymer-protein composites obtained by adsorption of proteins on the present porous copolymer also are industrially useful and have a wide variety of applications.
摘要:
A process for separation of uranium isotopes by chromatography through an anion exchange material is found to be improved in efficiency of separation as well as in productivity by addition of a catalyst for accelerating electron exchange reactions occurring in the system under conditions to retain uranyl ions on the anion exchange material preferentially over uranous ions.
摘要:
An oscillation limiting mechanism 4 is integrally provided to an engine mount 3 (a vibration proof mount device) of a power plant P mounted on an automobile in a traverse mount fashion. Not only is a stopper metal member 40 in the shape of an inverted U letter disposed so as to cross over a mount body portion 30, but a stopper rubber 42 is formed so that it protrudes from the rear end of a casing of the mount body portion 30 toward the rear side of the vehicle body. Not only is a hollow portion 43 formed in the interior of the stopper rubber 42, but a metal core body 44 is also embedded in the stopper rubber 42 so as to be revolvable around an axis in the vehicle body traverse direction as if it were a link. With such a construction adopted, the stopper rubber 42 is shear-deformed in the vertical direction with comparative ease even in a state where it is brought into contact with the rear side leg portion 40c of a stopper metal member 40 and thereby receives a compressive force in the vehicle body longitudinal direction, and a dynamic spring constant of the mount 3 in the vertical direction does not rise so much even if the stopper acts in rapid acceleration or the like; therefore, enabling increase in surrounding sound in acceleration to be suppressed with a simple structure less of cost up while oscillation of the power plant P is limited in a similar way to that of a torque rod.