Abstract: Disclosed is a composite membrane for removing water from dilute organic or inorganic acids by pervaporation or vapor permeation. The composite membrane in accordance with the invention is of a porous carrier layer, a porous backing layer, and a non-porous separating layer, which consists of a PVC-PCac copolymer having a PVac content of 10 to 25% by weight of the copolymer.

Abstract: A multilayer membrane is composed of a carrier layer, a porous supporting layer and a separating layer. The carrier layer consists of fibers of polyamide, polyvinylidene difluoride, polyester or glass; the porous supporting layer consists of a polysulfone, polyvinylidene difluoride, polyethersulfone, polyimide, polyvinyl alcohol, polyurethane, polyacrylonitrile or polyether imide; the separating layer consists of polyvinyl alcohol. The separating layer is nonporous and has a structure having a high microcrystalline content. A process of manufacturing that membrane is also described.

Abstract: The process of making a multilayer membrane composed of a carrier layer, a porous supporting layer and a separating layer includes making a modified polyvinyl alcohol by decomposing a polyvinyl ester or ether until the proportion of the vinyl alcohol monomer units in the modified polyvinyl alcohol corresponds to that in a material consisting of 80 to 95% of the polyvinyl ester or ether and 20 to 5% of a polyvinyl alcohol obtained by completely decomposing the polyvinyl ester or ether; preparing a composite material consisting of the carrier layer and the porous supporting layer, preparing a dilute aqueous solution containing 1 to 10% by weight of the modified polyvinyl alcohol; preferably storing the dilute solution at temperatures from -10.degree. to +10.degree. C., preferably from 0.degree. to 5.degree. C.

Abstract: A process is described for the production of alcoholates from alkali metal hydroxides and aliphatic alcohol which in their molecule contain 1 to 6 carbon atoms. The alcoholates are produced in that alkali metal hydroxide is mixed with an alcohol and is reacted with said alcohol at a temperature from 80.degree. to 110.degree. C., preferably from 80.degree. to 100.degree. C., and under a pressure from 0.3 to 1.2 bars, the alcohol water mixture which evaporates during the reaction is separated into its components by at least one membrane, the alcohol vapor and the water vapor are condensed and the condensed alcohol is recycled to the reaction.

Abstract: The dispenser is operable with an identification card carrying all data necessary for dispensing of money, and either a code number or a check, also carrying all data necessary for dispensing of money, and the dispenser is connected to a central computer having access to all data relative to a dispensation of money. The card contains automatically readable information identifying the issuing bank and, when the card is inserted into the dispenser, it is checked for authenticity in a card check and is read in a reading station, the card check and the reading station supplying outputs to a control unit and the reading station supplying an output to a comparator and an outout to blocked accounts store. The card then passes through an on-off line reading station, whose output is connected to the control unit, and to a gate station where the card is temporarily retained.

Abstract: This disclosure is directed to a conveying system for transporting documents from the delivery end of one conveyor section to the spaced apart entry end of a receiving conveyor section in a manner wherein the document is stiffened by imparting undulating or corrugated folds therein as it is conveyed so as to facilitate the transfer of the document from one conveyor to the next and thereby permitting at least one or both sides of the document to be checked or read as it is being conveyed from one station to the next at the point of transfer.