Societa' Italiana Resine S.i.r. S.p.a.

Euteco, S.p.a.

Euteco Impianti S.p.a.

Societa' Italiana Resine S.p.a.

Ing. Luigi Conti Vecchi S.p.a.

Luigi Piccolo

Antonio Paolinelli

Tullio Pellizzon

Marcello Ghirga

Benedetto Calcagno

Gabriele Bottai

Angelo La Rovere

Giorgio Cozza

Peter Schwarz

Tullio Corsini

Piero D Croce

Gian Pietro Paganessi

Gaudenzio Ferri

Emilio Bossi

Method of extracting magnesium sulphate from mixtures constituted essentially of magnesium sulphate heptahydrate and sodium chloride by means of heat treatment, grinding and dry grading.

Method of obtaining magnesium sulphate from mixtures of salts

Ferrous sulphate heptahydrate obtained as a by-product of the production of titanium dioxide by the sulphate process is converted into a non-polluting, free-flowing particulate neutralization product by contacting said sulphate with calcium hydroxide as a neutralizing agent in a molar ratio between said neutralizing agent and said ferrous sulphate of at least 1:1, and reacting the resulting mixture under agitation at a temperature not exceeding 60.degree. C. and for a contact time not exceeding five minutes.

Method for converting into a non-polluting particulate product the

This invention describes the preparation of a red pigment of iron oxide from ferrous salts, by simultaneous reduction of organic nitro derivatives.

Process for preparing a red pigmentary iron oxide

Aromatic amines and iron oxide pigment are produced by reacting a ferrous salt, a reduceable aromatic nitrogen compound chosen from nitroderivatives with a single nitro-group or with two nitro-groups and azoderivatives, and a basic compound, chosen from hydroxides and carbonates of ammonium, alkali metals and alkaline earth metals, operating at 25.degree.-200.degree. C. in an aqueous medium. The color of the pigment can be varied from yellow to black by increasing the reaction temperature and the molar ratio between ferrous salt and aromatic nitrogen compound.

Process for the joint production of aromatic amines and iron oxide

This invention describes a process for preparing a yellow iron hydroxide pigment from inorganic ferrous salts and aromatic nitro compounds.

Process for the preparation of yellow iron hydroxide pigment

This invention describes a process for preparing a red iron oxide pigment from inorganic ferrous salts and aromatic nitro compounds.

Process for preparing a red iron oxide pigment

Hydrolysis of a titanyl sulphate solution is carried out according to the autonucleation method of gradually adding the solution to a body of water at a substantially constant rate over 10-20 minutes, in such a way as to obtain an ionic concentration after one minute of feeding of from 75 to 105 g/l, the concentration of sulphuric acid in the final hydrolysis solution being regulated to a value of from 310 to 330 g/l by adding water from the commencement of clouding of the hydrolysis solution up to the end of hydrolysis.

Process for the hydrolysis of titanyl sulphate solutions

A soil modifier comprising from 80 to 95% by weight of a mixture of ferric oxide and ferric sulphate in an oxide/sulphate weight ratio of from 0.25:1 to 1:1, is prepared by calcining at 500.degree.-600.degree. C in an oxidizing atmosphere a blend of by-product obtained in the manufacture of titanium oxide by the sulphate process, with at least 20% by weight with respect to said by-product, of a material based on ferric sulphate and/or ferric oxide. Calcining is then continued under the same conditions, replacing said material in the blend continuously fed in by a recycle fraction of the product continuously discharged.

Method for the manufacture of soil modifiers from waste materials of the

Novel compositions for use in agriculture as soil improvers and fertilizers comprising as essential components ammonium sulfate and ferric oxide hydrate. By-products obtained in the production of titanium dioxide from ilmenite or ilmenite slag in the sulfate process and substantially consisting of ferrous sulfate heptahydrate are reacted with ammonia and that the reaction product obtained, consisting substantially of ammonium sulfate and ferrous hydrate, is subsequently oxidized until a composition is obtained which substantially consists of ammonium sulfate and ferric oxide hydrate.

Novel composition for use in agriculture as soil improvers and

A soil modifying composition and a concentrated solution of ammonium sulphate with a high purity degree are obtained from by-products consisting essentially of ferrous sulphate heptahydrate, obtained in the production of titanium dioxide from ilmenites by the sulphate process, by contacting solid particles of said by-products with gaseous ammonia, lixiviating the resulting product with water, thereby to recover said concentrated solution of ammonium sulphate, the dried residual solid yielding said soil modifying composition.

Process for the preparation of fertilizers and soil modifiers

Titanium dioxide is post-treated by flowing it in a tubular zone as a suspension in a stream of carrier gas, injecting a gaseous stream of halides of Si, Ti and Al in said stream and then steam in the resulting mixture, once the latter is homogenized.

Process for the post-treatment of titanium dioxide pigments

Soil modifiers comprising from 80 to 95% by weight of a mixture of ferric oxide and ferric sulphate in an oxide/sulphate weight ratio of from 0.2:1 to 2:1 are prepared by calcining at 500.degree.-600.degree. C in the presence of an oxidizing gas a material consisting essentially of ferrous sulphate with an average number of molecules of crystallization of from 1 to 5 obtained by partial dehydration of the waste materials, consisting essentially of ferrous sulphate heptahydrate, obtained in the manufacture of titanium dioxide from ilmenites or ilmenite slags by the sulphate process. These modifiers are particularly suitable for clay soils.

Method for the manufacture of soil modifiers from waste material of the

A solution of active nuclei for the hydrolysis of titanium sulphate and for the rutilisation of titanium dioxide in the manufacture of titanium dioxide in tutile form in the method via sulphate is prepared by transforming titanium tetrachloride into a compound of the formula Ti(OH).sub.x Cl.sub.y, wherein x ranges from 1 to 3, y from 3 to 1 and x + y is equal to 4 by contact with steam in the vapor phase, and contacting the reaction products with an aqueous solution of sodium hydroxide to form an aqueous suspension of titanium hydroxide having a TiO.sub.2 content of from 10 to 30 grams/liter and a pH value of from 3 to 4.

Manufacture of titanium dioxide by the sulphate process using nuclei

Titanium sulphate solutions obtained in the sulphate process from titaniferous materials are hydrolized by contacting at 88.degree.-98.degree. C water with a first titanium sulphate solution having a TiO.sub.2 titer of 230-260 g/l and an acid factor of 1.75-1.85, adding at 88.degree.-98.degree. C to the mixture a second titanium sulphate solution having a TiO.sub.2 titer of 230-260 g/l and an acid factor of 2.1-2.4 and heating the resulting mixture at boiling point. A volumetric ratio of from 3:100 to 12:100 is maintained between the first and the second solution.

Process for the hydrolysis of titanium sulphate solutions

A process for the joint production of titanium dioxide and sodium tripolyphosphate from ores of titanium and phosphorus, and from sulphuric acid, in which the titanium dioxide is produced by the 'sulphate process' and the impure dilute aqueous solution of sulphuric acid resulting therefrom is concentrated and used in the initial attack of phosphatic ones to provide a solution containing vanadium and chromium which can be removed without requiring any preventive conversion. The resulting sodium phosphate is then converted to sodium tripolyphosphate in a known way.

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Milan, Italy

Luigi Piccolo