Ozonated lignosulfonates

Claim 2

An ozonated composition comprising a lignosulfonate that has been subjected to ozone oxidation in an aqueous alkaline solution; said lignosulfonate being first incorporated in an aqueous dispersion containing between about 10 percent and 60 percent by weight of solids; said dispersion then having incorporated therein a base in an amount of at least 1 percent by weight of said lignosulfonate to form said alkaline solution prior to ozone oxidation; said lignosulfonate containing between 2 percent and 20 percent by combined oxygen after ozone oxidation by weight of said ozone oxidized lignosulfonate; said lignosulfonate containing between about 0.5 percent and about 15 percent, based on total unoxidized lignosulfonate, of sulfonic sulfur calculated as sulfur; said ozone oxidized lignosulfonate including, as its oxidized units, carboxylic and phenolic moieties.

Claim 3

An ozonated composition as claimed in claim 1, wherein said composition contains about 5 percent to about 10 percent of combined oxygen.

Claim 4

An ozonated composition as claimed in claim 1, wherein said lignosulfonate is a partially desulfonated alkaline oxidized, hydrolyzed, and sequentially resulfonated lignosulfonate.

Claim 5

An ozonated composition as claimed in claim 1, wherein said base contains an alkaline earth metal or an alkali metal or mixtures thereof.

Claim 6

An ozonated composition as claimed in claim 4, wherein said base is a hydroxide.

Claim 7

An ozonated composition as claimed in claim 5, wherein said hydroxide is calcium hydroxide or sodium hydroxide.

Claim 8

An ozonated composition as claimed in claim 1, wherein said sulfonic sulfur is present in combined form with said lignosulfonate in the form of units of the formula: --(CH 2 ) x SO 3 H, wherein x has a numerical integral value of from 0 to 3 inclusive.

Claim 9

An ozonated composition as claimed in claim 7, wherein said sulfonic sulfur is present as the sulfonic group of the formula --SO 3 H.

Claim 10

An ozonated composition as claimed in claim 7, wherein said sulfonic sulfur is present as a sulfomethyl group of the formula --CH 2 SO 3 H.

Claim 11

An ozonated composition as claimed in claim 7, wherein said sulfonic sulfur is introduced into said lignosulfonate to constitute 1.5 percent to 15 percent by weight of said lignosulfonate in its unoxidized state, by after-sulfonation of said previously ozone oxidized lignosulfonate.

Claim 12

An ozonated composition as claimed in claim 10, wherein said after-sulfonation is accomplished in an aqueous reaction mass at a temperature between about 40° C. and 200° C. using as the resulfonation reagent an aldehyde of the formula: RCH:O, wherein R is a hydrogen or an alkyl group containing from 1 to 2 carbon atoms in approximately stoichiometric admixture with a sulfite of the formula: XHSO 3 , wherein X is an alkali metal.

Claim 13

An ozonated composition as claimed in claim 10, wherein said aldehyde is formaldehyde and said sulfite is sodium bisulfite; and wherein said temperature is at least about 100° C. for a period of from 0.5 hour to about 16 hours.

Claim 14

An ozonated composition as claimed in claim 4, wherein said base is present in an amount of from about 10 percent to 15 percent by weight of said lignosulfonate.

Claim 15

An ozonated composition as claimed in claim 13, wherein said base is present in an amount of about 13 percent.

Claim 16

An ozonated lignosulfonate composition consisting essentially of a lignosulfonate that has been subjected to ozone oxidiation in an aqueous alkaline solution at a temperature within the range of 0° C. to 80° C. for a period of at least 30 minutes by means of a continuous ozone feed to said lignosulfonate; said aqueous alkaline solution of lignosulfonate having been formed from an aqueous dispersion of said lignosulfonate containing from about 10 percent to 60 percent by weight of solids to which a base is added; said ozone feed comprising a gaseous composition composed of oxygen or air and containing from 0.1 percent to 5 percent by weight of ozone; said ozonated lignosulfonate containing, by weight, between 2 percent and 20 percent of total added combined oxygen in the oxidized lignosulfonate product; said composition being further characterized by substantially complete solubility in aqueous saline solution.

Claim 17

An ozonated lignosulfonate composition consisting essentially of a lignosulfonate that has been subjected to ozone oxidiation in an aqueous alkaline solution at a temperature within the range of 0° C. to 80° C. for a period of at least 30 minutes by means of a continuous ozone feed to said lignosulfonate; said aqueous alkaline solution of lignosulfonate having been formed from an aqueous dispersion of said lignosulfonate containing from about 10 percent to 60 percent by weight of solids to which a base is added; said ozone feed comprising a gaseous composition composed of oxygen or air and containing from 0.1 percent to 5 percent by weight of ozone; said ozonated lignosulfonate containing, by weight, between 2 percent and 20 percent of total added combined oxygen in the oxidized lignosulfonate product; said composition being further characterized by substantially complete solubility in aqueous saline solution.

Claim 18

An ozonated oxidized composition as claimed in claim 15, wherein said ozone oxidation takes place at a temperature of from 20° C. to 50° C. for a period of 2 to 7 hours.

Claim 19

An ozone oxidized composition as claimed in claim 16, wherein the concentration of ozone in said feed is within the range of 2 percent to 3 percent by weight of said gaseous composition.

Claim 20

An ozone oxidized composition as claimed in claim 17, wherein said aqueous alkaline medium has a pH of about 14.

Claim 23

The method of claim 19, wherein said ozone is present in an air or oxygen carrier in a concentration therein of between about 0.1 percent and about 4 percent.

Claim 24

The method of claim 19, wherein said ozone is present in a concentration of from about 2 percent to about 3 percent.

Claim 25

The method of claim 19, wherein ozone oxidation is conducted for a period of between about 1/2 hour to about 16 hours.

Claim 26

The method of claim 19, wherein the ozone take-up is between about 5 percent and about 10 percent.

Claim 27

The method of claim 19, wherein the lignosulfonate starting material comprises an alkaline oxidized, hydrolyzed, partially desulfonated lignosulfonate in an aqueous dispersion containing between about 10 weight percent and about 60 weight percent of dispersed lignosulfonate solids.

Claim 28

The method of claim 19, wherein said alkaline reagent is sodium hydroxide or calcium hydroxide.

Claim 29

The method of claim 19, wherein the lignosulfonate starting material contains between about 1/2 percent and about 15 percent, based on total unoxidized lignosulfonate solids weight, of organic sulfonic sulfur calculated as sulfur.

Claim 30

The method of claim 26, wherein said lignosulfonate starting material contains between about 11/2 percent and about 10 percent of organic sulfur.

Claim 31

The method as claimed in claim 19, including in addition thereto and in combination therewith: the additional step of introducing into the ozone oxidized lignosulfonate product by after-sulfonation to make up between about 11/2 weight percent and about 15 weight percent of total sulfur in combined organic sulfonic sulfonate form, based on the weight of the resulting composition, of units of the formula: (--CH 2 ) x --SO 3 H, wherein x has a numerical integral value from 0 to 3.

Claim 32

The method of claim 28, wherein the resulfonation units are sulfonyl radicals of the formula --SO 3 H.

Claim 33

The method of claim 28, wherein said sulfoalkyl groups are sulfomethyl groups.

Claim 34

The method of claim 28, wherein said after-sulfonation is accomplished in an aqueous reaction mass at a temperature between about 50° C. and 200° C. using as the resulfonation reagent an aldehyde of the formula: RCH:O, wherein R is hydrogen or an alkyl group containing from 1 to 2 carbon atoms in approximately stoichiometric admixture with a sulfite of the formula: XHSO 3 , wherein X is an alkali metal.

Claim 35

The method of claim 31, wherein said aldehyde is formaldehyde and said sulfite is sodium bisulfite; and said temperature is at least about 100° C. for a period of from about 1/2 hour to about 16 hours.

Claim 36

The method of claim 19, wherein said ozone oxidation is conducted at a temperature within the range of 0° C. to 80° C.

Claim 39

The method of claim 34, wherein said lignosulfonate-containing, alkaline aqueous medium contains from 1 percent by weight of alkali to the maximum soluble concentration of alkali therein.

Claim 40

The method of claim 35, wherein said alkali is present in an amount by weight of from about 10 percent to about 15 percent.

Claim 41

The method of claim 36, wherein said alkali is present in an amount by weight of about 13 percent.

Claim 42

The method of claim 33, wherein the temperature at which ozone oxidation is effected is between about 20° C. and 50° C.

Claim 43

The method of claim 33, wherein said temperature is between about 40° C. and 50° C.; and said ozone oxidation is conducted for a period of from about 2 hours to about 7 hours.