I/EC the phosphorus
REPORTS
and 20 to 50% of the
silica. The iron-rich solids, with an iron content now ranging from 45 to 50%, can be agglomerated and fed to a blast furnace. Ratio of pig iron to slag is about 2:1, compared to a 1:1 ratio from the untreated ore. The hot caustic leaching solution can be re-used without chemical treatment until the silica content reaches 1 5 % or so. It can then be regenerated by treating with lime to precipitate most of the phosphates and some of the silica and alumina. Caustic recovery and re-use are a key step, because the technique requires a ratio of five parts of it per part of ore. This is just a start. Dr. Herzog emphasizes that his results to date show only that chemical enrichment of the Lorraine ore might be econom ically feasible. During his semiworks trials now going on, he will be firming up, in addition to costs, the chemistry of the reversion of the un dissolved nonmagnetic iron oxides to magnetic oxides. Among the clues about this reaction : traces of calcium and silicates favor it. D.E.G
hioh 4M0P?
MWM
m ******* ΡΜΗΤΤΓΙ
nign highefficiency pump design destructive velocities
Capacities to 600 gpm., heads to 180 feet. Pedes tal assemblies available for base-mounted coup ling connections. Closecoupled connections f i t NEMA standard pump motors.
... saves you money on maintenance
Skin for Satellites A unique class of coat ings based on silicate glasses are excellent, stable reflectors. I HE IDEAL place to put a tempera
ture control system in spacecraft is in the outer skin. Many ingenious systems, both active and passive, have been suggested. For long-term use, the passive system, made up of a mosaic of absorbing and reflecting surfaces, seems best. This is the type of system chosen for the MIDAS project. All that a passive coating must do is remain unchanged. But these are the conditions under which it must do nothing: • Vacuum of 10~12 mm. of mercurypressure • Temperature ranges of 140° to - 6 5 ° C. {Continued on page 30 A)
Ampco Centrifugal Pump in 3 1 6 Stainless Ampco's modern design lengthens pump-life and steps up efficiency several ways: Interface velocity is reduced — losses by hydraulic friction, shock, and turbulence are practically nil. Velocity, corrosion and abrasion are held to a minimum. Pressure break-down areas are re stricted to parts that are inexpen
sive and convenient to replace. Casing and shaft are protected — new-pump characteristics are main tained longer. In addition to stainless steel, Ampco Centrifugal Pumps are available in AMPCO® aluminum bronze and Illium "G." Elastomer-lined pumps are also available. Representatives in principal industrial areas. Write for Bulletin P-3c. Do it today. Ρ·4β
Don't overlook ... it's a yardstick performance!
EFFICIENCY of.
AMPCO
METAL, INC.
DEPT. 1 4 9 K , MILWAUKEE 1 , WIS.
West Coast Division: Huntington Park, Calif. · Southwest Division: Garland (Dallas County), Texas Circle No. 33 on Readers' Service Card VOL. 53, NO. 11 ·
NOVEMBER 1961
29A
I/EC
REPORTS
• Ultraviolet radiation of 2 calories per sq. cm. per minute, in the 2000- to 4000-A. range • Exposure to Van Allen and cosmic radiation • Contact with aluminum and mag nesium substrates
ZIRCONIUM ACETATE SOLUTION, 22% Zr0 2
Introduced to meet the many demands for a more concentrated solution, ΤΑΜ Zirco nium Acetate Solution, 22% Zrik, is now available to the chemical industry. Colon Clear to very light amber Specific Gravity: 1.46 pH: 3.8 to 4.2 at 20° C Stable indefinitely at room temperature
APPLICATIONS ARE: 1. As an ingredient in "renewable" type water repellents for textiles. 2. As a catalyst for curing silicone resins in water-repellent treatments for leather and textiles. 3. For precipitation and fixation of many protein or carbohydrate type molecules (such as gelatin and starch) upon paper and fabrics.
To meet specifications, properties of a coating should change by only 3 to 5 % over a one to two year period. M. E. Sibert, of Lockheed Aircraft Corp.'s Missiles and Space Division feels that a satisfactory material has been found for the reflective part of the surface. Vacuum and radiation require ments alone eliminate all organicbased coatings—leaving only phos phate and inorganic systems. Thus far, nearly ideal formulations are based on silicate glasses, and are analogous to conventional paints. Like conventional paints, these coatings are composed of pigmentvehicle combinations, modified by inorganic additives. Successful vehicles are alkali silicates, with the highest silica contents preferred. Potassium silicate has some advan tage over those of lithium and sodium, mainly because it is available in higher purity. The best pigments are refractory silicates, especially zirconium and
Send for Data File
ΤΑΜ Executive and Sales Offices
Works and Research Laboratories Niagara Falls, N.Y.
Please direct
H M ^*BI^L
FOR
Zr COMPOUNDS AND
inquiries to our CHEMISTRY New York City offices Circle No. 3 on Readers' Service Card
30 A
calcium silicates. These showed far better resistance to change than other materials tested, which in cluded titanates, zirconates, niobates, tantalates, and several ceramic ma terials. Properties of the finished coating are changed greatly by choice of total solids content, pig ment particle size, and solid-liquid ratio. But optimum formulations have been determined. Fortunately, preparation and application procedures commonly used in the paint industry are suit able for MIDAS coatings. Ballmilling techniques are used to pre pare the compositions, with milling times of 24 to 96 hours. The coating may be applied by brushing, dipping, or spraying, followed by curing at 150° to 200° C. for between one and three hours. Aluminum substrates need no surface treatment, but roughening and a surface coating are needed for aluminum alloys and magnesium substrates. A thickness of about 5 mils is required, built up by two or three thin coats. A surprising property is the appar ent flexibility of these inorganic materials. These coatings have shown satisfactory adherence and coherence in spite of: • Thermal shock between 100° and - 7 0 ° C. • Vibration tests to 10,000 cycles • 180° bend tests over 3 / 4 - and 1/2inch mandrels
High-Flying Adhesives
DIVISION NATIONAL LEAD COMPANY
General Offices
INTERPRETS
This new class of coatings, de veloped for space applications, is arousing considerable interest in the very active coatings field. Their unique chemical composition may provide a new means of protection for specific CP1 uses. E.W.M.
SHIPPED in 500 lb. (net) drums with P. E. drum inserts.
111 Broadway (Dept. IC), New York 6, N.Y.
AND
Inorganic coatings, b a s e d on silicates, protect nose cone a g a i n s t marked changes in t e m p e r a t u r e . Conven tional methods a r e used to a p p l y the coatings
INDUSTRIAL AND ENGINEERING CHEMISTRY
IVlANNED SPACE flight will use a honeycomb sandwich construction as an integral part of the vehicle. Low weight and structural strength arc the outstanding features of the honeycomb construction. But air foil heating—up to 600° F.—makes it imperative that sandwich ad hesives be capable of maintaining their strength at high temperatures.
