摘要:
A process for purification of crude glyceride oil compositions which comprises diluting a crude glyceride oil composition containing gum material and wax as main components of impurities with an organic solvent, bringing the diluted crude glyceride oil composition into contact with a semipermeable membrane composed of polyimide consisting essentially of a repeating unit represented by the general formula: ##STR1## wherein R.sup.1 represents a divalent organic group, under pressure to obtain a semipermeable membrane permeable liquid in which the gum material in the glyceride oil after removal of said organic solvent is 100 ppm or less, carrying out bleaching of the glyceride oil obtained from said semipermeable membrane permeable liquid with at least one kind of an adsorbent selected from the group consisting of clay, activated clay, activated carbon and bone black, and then carrying out deodorizing to obtain a purified glyceride oil.
摘要:
A composite membrane and a process for producing the same are described. This composite membrane comprises a polyimide resin anisotropic membrane and a cross-linked silicone resin thin film formed on the anisotropic membrane, the anisotropic membrane comprising a dense surface layer and a porous layer continuously connected thereto and the polyimide resin consisting essentially of a repeating unit of the formula: ##STR1## wherein A and R.sup.1 are the same as defined hereinbefore. This composite membrane is useful for separation of organic solutions containing relatively small solutes of molecular weight of the order of 10 to 1,000 liquid/liquid separation, and concentration and separation of gases.
摘要:
A pressure sensitive adhesive sheet for the detection of microorganisms, which comprises a laminate of an adhesive layer mainly composed of a water-soluble polymer and a water-permeable membrane which does not allow passage of the microorganisms; a pressure sensitive adhesive sheet for the detection of microorganisms, wherein the surface of the adhesive layer has a contact angle with water of not more than 90°; and a method for detecting a microorganism, which comprises bringing the surface of an adhesive layer of a pressure sensitive adhesive sheet into contact with the surface of a test object, and then bringing the surface of the adhesive layer into contact with water, said adhesive layer or water containing a chromogenic reagent. The use of the laminate makes it possible to leave only stained microorganisms on the water-permeable membrane and to precisely observe the color developed by the microorganisms. The method of the present invention enables real-time monitoring without culture of microorganisms, and is not limited to the detection of viable cells alone. Inasmuch as a contact of the pressure sensitive adhesive sheet with a test face results in accumulation of microorganisms, the manipulation is simple. In addition, by properly determining a chromogenic reagent, a specific microorganism alone can be detected and counted, so that it can be applied to environmental investigation in the medical field, food industry field and the like.
摘要:
A selective permeable membrane and a process for preparing the membrane. The process comprises applying to a supporting substrate a membrane forming solution prepared by dissolving in an organic solvent a polyimide polymer comprising principally a repeating unit represented by the general formula (I): ##STR1## wherein R.sup.1 represents a divalent organic group, and a liquid swelling agent having a coagulation value with respect to the polyimide polymer of about 50 to about 200 and a boiling point of about 50.degree. C. to about 120.degree. C. under atmospheric pressure, evaporating at least a part of the swelling agent, and coagulating the polyimide polymer by contacting the polyimide polymer with a coagulating solvent which does not dissolve the polyimide polymer but is compatible with the organic solvent and the swelling agent.
摘要:
A process for producing a composite membrane is disclosed. The composite membrane is produced by bringing an organic solution of a specific cross-linkable silicone resin into contact with the surface of a dense layer of an anisotropic membrane made of a polyimide resin. The composite membrane is useful for separation of an organic solution containing a relatively small solute, liquid/liquid separation by pervaporation method, and concentration and separation of gases.
摘要:
A process for the purification of crude glyceride oil compositions which comprises bringing a miscella of a crude glyceride oil composition containing therein a glyceride oil and phospholipid into contact with a capillary semipermeable membrane to concentrate the miscella to a predetermined level, and thereafter bringing the preliminarily concentrated miscella into contact with a tubular semipermeable membrane to concentrate the miscella to a higher level.
摘要:
A process for preparing a selective permeable membrane having self-supporting property, which comprises coating on a supporting substrate a dope comprising a polyimide polymer consisting essentially of a repeating unit of the formula: ##STR1## wherein R is a divalent organic group, an inorganic salt and an organic solvent, as a dope solvent, which dissolves a mixture of the polymer and the inorganic salt to form a homogeneous system, to prepare a dope coated supporting substrate, heat treating the substrate at a temperature which does not cause the organic solvent in the dope to boil, and then coagulating the substrate.
摘要:
A process is described for preparing a selective permeable membrane comprising coating a solution consisting essentially of(i) a polyimide polymer consisting essentially of a repeating unit of the formula (I): ##STR1## wherein R.sup.1 is a divalent organic group, (ii) a swelling agent selected from the group of compounds represented by formula (II) and (III):R.sup.3 O----CH.sub.2 CHR.sup.2 O).sub.n R.sup.4 (II)R.sup.5 ----OH).sub.m (III) wherein R.sup.2, R.sup.3 and R.sup.4, which may be the same or different, can be hydrogen, a methyl group, or an ethyl group, and when R.sup.2 is hydrogen, n can be an integer of from 1 to 5, and when R.sup.2 is a methyl or ethyl group, n can be an integer of from 1 to 3, R.sup.5 is a saturated aliphatic hydrocarbon group containing 3 to 6 carbon atoms, and m can be an integer of from 2 to 6, and(iii) an organic solvent,on a supporting substrate, and immersing the solution coated supporting substrate in a coagulating liquid which does not dissolve the polyimide polymer and is miscible with the organic solvent, to coagulate the polyimide polymer and form the membrane. Membranes prepared by the process are also described.