Abstract: A process for preparing microporous separating elements for batteries by intensive mixing of a high molecular weight polyethylene with a precipitated silica having specific chemical and physical characteristics, a process liquid and a stabilizer to form a powder mixture, which is extruded to form a film, from which the process liquid is removed, thereby leaving the desired microporous separating elements which are recovered.

Abstract: Precipitated silica with the following physical-chemical characteristics:______________________________________ BET surface: DIN 66131 100-130 m.sup.2 /g DBP absorption DIN 53601 .gtoreq.275 g/100 g (anhydrous) ASTM D 2414 Loss on drying DIN ISO 787/II (2 h/105.degree. C.) ASTM D 280 3.5-5.5 wt. % JIS K 5101/21 Oversize with ALPINE air-jet sieve: >63 .mu.m .ltoreq.10.0 wt. % >150 .mu.m .ltoreq.0.1 wt. % >250 .mu.m .ltoreq.0.01 wt. % Chloride content: .ltoreq.100 ppm ______________________________________is prepared by introducing water into a precipitation vessel, adding water glass until an alkali value of 5-15 is reached, then adding further water glass and sulfuric acid simultaneously, interrupting the precipitated silica suspension with sulfuric acid to a pH-value of 8.5, with stirring, then continuing acidification with concentrated sulfuric acid to a pH-value of 4, then separating and washing the precipitated silica which has a solids content in the suspension of approx.

Abstract: Precipitated silicas which have the following physicochemical characteristics, depending on the manner in which they are milled:______________________________________ Pendulum roller mill Jet mill ______________________________________ BET m.sup.2 /g 15-110 15-110 surface area Tamped g/l 150-750 90-650 den- sity Cu abrasion in 10% mg 5-30 5-30 strength glycerol dispersion Lightness % 86-96 90-96 value Particle size dis- as in FIG. 1 as in FIG. 2 tribution curve determined by a Coulter Counter "ALPINE screen retain- % by <1.5 <0.1 ings" >63 .mu.m weight Viscosity of a 30% mPa.s 30,000 to 60,000 strength dispersion in a 1:1 glycerol/water mixture (Brookfield RTV, Sp5) ______________________________________are prepared by diluting a precipitated silica original suspension obtained according to German Published Application DAS 1,467,019 and simultaneously adding alkali metal silicate solution, sulfuric acid and water while keeping the pH constant between 7 and 9.

Abstract: There are disclosed precipitated silicas which are characterized by the following physical-chemical data:______________________________________ A B C ______________________________________ BET-surface area m.sup.2 /g 400-600 400-600 400-600 according to DIN 66131 DBP-Number % 340-380 320-360 310-360 Bulk density according g/l 180-220 75-120 35-70 to DIN 53194 "ALPINE-Sieve Wt. % 25-60 <0.1 <0.01 Residue" >63 m.mu. ______________________________________Depending on the particle distribution curve, these precipitated silicas can be employed as silica carriers for active materials of all types, as antiblocking agents for polypropylene and polyethylene films, as thickening silica in specific polar systems in which pyrogenic silicas show little thickening capacity, as highly active matting agents for varnishes and as catalyst carriers as well as insulating materials.

Abstract: There are produced mixed granulates of carbon black-light filler using carbon black and an aqueous suspension of a light filler, e.g. precipitated in a pin containing screw granulator.

Abstract: Precipitated, jet ground silica with specific physical-chemical properties is mixed with silicone oil, homogenized and heated to produce an antifoam agent. This type of antifoam agent can be used in pharmacy, in producing foam stopping latex emulsion, in the food field, in washing formulations, in the textile industry as well as in the pigment and varnish industries.

Abstract: Silicon dioxide containing waste flue dust from the production of silicon metal and silicon alloys is converted to crystalline zeolite molecular sieves of type A by (1) dissolving the flue dust in alkali metal hydroxide solution with the formation of alkali metal silicate solution having a module (SiO.sub.2 :Me.sub.2.sup.I O) in the range of 2.0:1 to 3.5:1 at a temperature of 60.degree.-100.degree. C.; (2) purifying the thus obtained alkali metal silicate solution from organic constituents by treatment with activated carbon and/or an oxidizing agent and separating the non-decomposable residue from the solution; and, (3) reacting alkali metal aluminate solution present at room temperature with the diluted, purified alkali metal silicate solution with a module (SiO.sub.2 :Na.sub.2 O) of 2.0:1 to 3.5:1 obtained by steps (1) and (2) and subsequently crystallizing the reaction mixture ((2.0-4.4)Na.sub.2 O:Al.sub.2 O.sub.3 ; (1.3-1.8)SiO.sub.2 :(90-120)H.sub.2 O) at a temperature of 90.degree.-95.degree. C.

Abstract: Finely divided precipitated silicic acid is obtained by the method of the invention.Compositions containing the finely divided precipitated silicic acid as a filler distributed in an elastomer such as an organopolysiloxane are disclosed.

Abstract: There is prepared precipitated silica containing boron and having the following physical-chemical data______________________________________ Loss on heating Weight % 14-40 pH 4-6 Conductivity in 4% aqueous /.mu.S <800 dispersion Bulk density g/l 130 .+-. 100 Sieve residue according to Alpine >63/.mu. Weight % <0.1 SiO.sub.2 content based on original Weight % 9-76 material B.sub.2 O.sub.3 content based on original Weight % 10-51 material Na.sub.2 O content based on original Weight % <0.5 material So.sub.3 content based on original Weight % <0.8 material ______________________________________The product is obtained by supplying precipitated silica and ortho boric acid in the ratio of 0.1-3.5:1 continuously to a jet mill and micronizing them together by means of the air of the mill at room temperature.

Abstract: Finely divided precipitated silicic acid is obtained by the method of the invention.Compositions containing the finely divided precipitated silicic acid as a filler distributed in an elastomer such as an organopolysiloxane are disclosed.

Abstract: There are provided thermoplastic polymer containing mixtures suitable for making synthetic resin films with antiblocking properties containing 0.05 to 70 weight % of a pulverulent zeolite.

Abstract: Silicon dioxide containing waste flue dust from the producton of silicon metal and silicon alloys is converted to crystalline zeolite molecular sieves of Type Y by (1) dissolving the flue dust in alkali metal hydroxide solution with the formation of alkali metal silicate solution having the module (SiO.sub.2 :Me.sup.I.sub.2 O) in the range of 4.0:1 to 5.0:1 at a temperature of 60.degree.-110.degree. C.; (2) purifying the thus obtained alkali metal silicate solution from organic constituents by treatment with activated carbon and/or an oxidizing agent and separating the non-decomposable residue from the solution; and (3) reacting alkali metal aluminate solution present at room temperature with the diluted, purified alkali metal silicate solution with a module (SiO.sub.2 :Me.sup.I.sub.2 O) of 4.0:1 to 5.0:1 obtained by steps (1) and (2) and subsequently crystallizing the reaction mixture (SiO.sub.2 :Al.sub.2 O.sub.3 =4-7:1, Me.sup.I.sub.2 O:SiO.sub.2 =0.4-0.7, H.sub.2 O:Me.sup.I.sub.

Abstract: Hydrophobic precipitated silicic acid is disclosed and its use as a reinforcing filler in plastic masses which are hardenable to form elastomers.

Abstract: There is provided a process for treating air-borne dust containing silicon dioxide in order to form a silicic acid or a silicate. The air-borne dust is dissolved in an alkali metal hydroxide solution to form an alkali metal silicate solution. The alkali metal silicate solution is purified by treating it with activated charcoal and/or oxidation agents. Non-decomposable substances remaining after the purification step are removed from the alkali metal silicate solution. The alkali metal silicate solution is then reacted with acids and/or salts of aluminum, magnesium and calcium. The resulting product is then filtered, washed and dried, and then comminuted to form a finely divided, amorphous, substantially pure, precipitated, silicic acid or silicate having a whiteness according to Berger at a wave length of 460 m.mu. of about 90 to about 95% and a specific surface area of about 30 to about 800 m.sup.2 /g BET.

Abstract: Free flowing, finely divided precipitated silicic acid granules of reduced dust content and reduced abrasion are obtained by a process including the step of subjecting a silicic acid suspension to intensive shearing action. Rubber compositions containing the precipitated silica produced in this way are also disclosed.

Abstract: Modified silicic acids, gels, and silicates are produced by impregnation with a wax or a thermoplastic material, such as polyethylene. The silicic acids, silica gels, or silicates can be impregnated either as they are being formed or after they have formed by adding an aqueous suspension or dispersion of wax thermoplastic material to the silicic acids, gels or silicates. The mixture is then filtered, washed, dried, and finely ground. The organically modified silicic acids, gels, and silicates are useful as delustering agents in lacquer systems.

Abstract: Superfine amorphous, high structure silicic acid is made by subjecting the components in the precipitation reaction, that is, an acid or acidic substance and an alkali-metal silicate solution to a shearing force during the alkaline phase of the precipitation reaction, the shearing force being applied by passing the reaction mass in a continuous flow through a dispersing device and the dispersing device being operated with an hourly throughput frequency of at least 10 h.sup..sup.-1, the said frequency being determined as the ratio of the performance of the dispersing device to the initial volume of the reaction mass.The high structure silicic acid is particularly useful as carrier and filler for pesticides, animal feed additives and as matting agent for lacquers.

Abstract: Superfine amorphous, high structure silicic acid is made by subjecting the components in the precipitation reaction, that is, an acid or acidic substance and an alkali-metal silicate solution to a shearing force during the alkaline phase of the precipitation reaction, the shearing force being applied by passing the reaction mass in a continuous flow through a dispersing device and the dispersing device being operated with an hourly throughput frequency of at least 10h.sup.- .sup.1, the said frequency being determined as the ratio of the performance of the dispersing device to the initial volume of the reaction mass.The high structure silicic acid is particularly useful as carrier and filler for pesticides, animal feed additives and as matting agent for lacquers.