Method of producing vanillin

Claim 1

A METHOD OF PRODUCING OXIDIZATION PRODUCTS INCLUDING THE CALCIUM DERIVATIVE OF VANILLIN FROM LIGNOSULFONIC ACID COMPOUNDS, THE INITIAL LIGNIN CONCENTRATION OF SUCH COMPOUNDS IN AN ALKALINE AQUEOUS MEDIUM, MEASURED AS HEREIN PRESCRIBED, BEING NOT MORE THAN 38 GRAMS PER LITRE NOR LESS THAN 10 GRAMS PER LITRE, THE SAID MEDIUM CONTAINING LIME AS THE ACTIVE, ALKALI IN AN AMOUNT SUFFICIENT TO MAINTAIN THE PH OF THE REACTION MIXTURE DETERMINED ON A SAMPLE WITHDRAWN FROM THE REACTION ZONE AND COOLED TO ROOM TEMPERATURE IN THE RANGE NOT LESS THAN 12 TO NOT MORE THAN THAT OF A SATURATED SOLUTION OF LIME IN THE SAME MIXTURE, WHICH COMPRISES INTRODUCING SAID COMPOUNDS INTO A REACTION ZONE, HEATING THE REACTION MIXTURE TO A TEMPERATURE NOT LESS THAN 120* C., NOR MORE THAN 200* C., MAINTAINING SAID ZONE UNDER SUPER-ATMOSPHERIC PRESSURE, CONTINUOUSLY PASSING A GAS CONTAINING FREE OXYGEN IN FINELY DISPERSED FORM THROUGH SAID REACTION ZONE, CONTINOUOUSLY REMOVING RESIDUAL GAS, THE RATE OF ADDITION AND REMOVAL OF SAID GAS BEING SUCH AS TO MAINTAIN A PARTIAL PRESSURE OF OXYGEN IN SAID ZONE OF LESS THAN 20 LB. PER SQUARE INCH, THE TIME OF SAID REACTION BEING LESS THAN FOUR HOURS.

Claim 2

A METHOD OF PRODUCING OXIDIZATION PRODUCTS INCLUDING THE CALCIUM DERIVATIVE OF VANILLIN FROM LIGNOSULFONIC ACID COMPOUNDS, THE INITIAL LIGNIN CONCENTRATION OF SUCH COMPOUNDS IN AN ALKALINE AQUEOUS MEDIUM, MEASURED AS HEREIN PRESCRIBED, BEING NOT MORE THAN 38 GRAMS PER LITRE NOR LESS THAN 10 GRAMS PER LITRE, THE SAID MEDIUM CONTAINING LIME AS THE ACTIVE, ALKALI IN AN AMOUNT SUFFICIENT TO MAINTAIN THE PH OF THE REACTION MIXTURE DETERMINED ON A SAMPLE WITHDRAWN FROM THE REACTION ZONE AND COOLED TO ROOM TEMPERATURE IN THE RANGE NOT LESS THAN 12 TO NOT MORE THAN THAT OF A SATURATED SOLUTION OF LIME IN THE SAME MIXTURE, WHICH COMPRISES INTRODUCING SAID COMPOUNDS INTO A REACTION ZONE, HEATING THE REACTION MIXTURE TO A TEMPERATURE NOT LESS THAN 120* C., NOR MORE THAN 200* C., MAINTAINING SAID ZONE UNDER SUPER-ATMOSPHERIC PRESSURE, CONTINUOUSLY PASSING A GAS CONTAINING FREE OXYGEN IN FINELY DISPERSED FORM THROUGH SAID REACTION ZONE, CONTINOUOUSLY REMOVING RESIDUAL GAS, THE RATE OF ADDITION AND REMOVAL OF SAID GAS BEING SUCH AS TO MAINTAIN A PARTIAL PRESSURE OF OXYGEN IN SAID ZONE OF LESS THAN 20 LB. PER SQUARE INCH, THE TIME OF SAID REACTION BEING LESS THAN FOUR HOURS.