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from undergoing extreme cycling during the operation of the reactor system. The feed rate of the olefin to the system is 224.4 grams per hour per liter of reaction volume. Table B summarizes results for several different feed compositions for temperature differences between the reaction and the temperature of the coolant entering the heat transfer means that prevent the system from undergoing extreme cycling. 

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Examples 2 to 6 illustrate the in situ buffering effect of nitrogen containing additives such as benzimidazole and the ability of these additives to transfer the acidity to an aqueous buffer solution. 

This control example illustrates the stability of Ligand D (as identified herein) in a solution containing 200 parts per million of rhodium, and 0.39 percent by weight of Ligand D in butyraldehyde containing aldehyde dimer and trimer in the absence of added acid or benzimidazole. 

To a clean, dry 25 milliliter vial was added 12 grams of the butyraldehyde solution mentioned above. Samples were analyzed for Ligand D using High Performance Liquid Chromatography after 24 and 72 hours. The weight percent of Ligand D was determined by High Performance Liquid Chromatography relative to a calibration curve. No change in the concentration of Ligand D was observed after either 24 or 72 hours. 

This Example is similar to Example 2 except that phos› phorus acid was added to simulate the type of acid that might be formed during hydrolysis of an organophosphite. 

The procedure for Example 2 was repeated with the modification of adding 0.017grams of phosphorous acid (Hi’O 3 ) to the 12 gram solution. After 24 hours the con› centration of Ligand D had decreased from 0.39 to 0.12 percent by weight; after 72 hours the concentration of Ligand D had decreased to 0.04 percent by weight. This data shows that strong acids catalyze the decomposition of Ligand D. 

## Example 2 

## Example 3 

This Example is similar to Example 2 except that both phosphorus acid and benzimidazole were added. 

The procedure for Example 2 was repeated with the modification of adding 0.018 grams of phosphorous acid and 0.0337 grams of benzimidazole to the solution. No decom› position of Ligand D was observed after either 24 or 72 hours. This shows that the addition of benzimidazole effec› tively buffers the effect of the strong acid and thereby prevents the rapid decomposition of Ligand D. 

This example shows that an aqueous buffer can recover the acidity from the nitrogen base in situ buffer and allow the nitrogen base to partition into the organic phase, where it can be recycled to the hydroformylation zone. 

Solid (benzimidazole)(H$_{3}$ P0$_{4}$ ) was prepared by placing 1.18 grams ( 10 mmole) of benzimidazole in a 250 milliliter beaker and dissolving the benzimidazole in 30 milliliters of tetrahydrofuran. To this solution was slowly added 0.5 grams of 86 percent by weight of phosphoric acid (H$_{3}$ P0$_{4}$ ). Upon addition of the acid a precipitate formed. The precipi› tate was collected on a sintered glass frit and washed with tetrahydrofuran. The resulting solid was air-dried with the application of vacuum and used without any further purifi› cation. 0.109 grams (0.504 mmole) of the water-soluble (benzimidazole)(H$_{3}$ P0$_{4}$ ) solid prepared in the previous step was dissolved in 10 grams of 0.lM pH 7 sodium phosphate buffer solution. The resulting solution was extracted with 10 grams of valeraldehyde. The organic layer was then sepa› rated from the aqueous layer using a separatory funnel. The volatile components were then removed from the organic layer by distillation at 100° C. to yield a solid. The solid was identical to authentic benzimidazole as shown by thin layer chromatography utilizing a 1: 1 by volume mixture of chlo› roform and acetone as the eluent and silica as the stationary phase. Based on recovery of the solid. benzimidazole was completely transferred to the organic phase. 

This data shows that an organic soluble nitrogen base which exists as a strong acid salt can be regenerated by contact with an aqueous buffer and returned to the organic phase. 

This example shows that a buffer solution is effective at neutralizing an organic soluble salt of a weak base and strong acid thus allowing the base to return to the organic phase and effectively removing the acid from the organic phase. 

A butyraldehyde solution was prepared containing 1.0 percent by weight of benzotriazole. The solution was then analyzed by Gas Chromatography for benzotriazole content to serve as a reference sample. To the solution prepared in the previous step was added 0.25 mole equivalents of phosphorous acid (H:J>()$_{3}$ ). In a one pint glass bottle was added 50 grams of the butyraldehyde solution containing benzotriazole and 50 grams of a pH 7. 0.2 molar sodium phosphate buffer solution. The mixture was stirred for 15 minutes and then transferred to a separatory funnel. The aqueous layer was then separated from the aldehyde layer. The aqueous layer was analyzed for H$_{3}$ P0$_{3 }$ content by Ion Chromatography. The aldehyde layer was analyzed for ben› zotriazole content by Gas Chromatography and H$_{3}$ P0$_{3 }$ content by Ion Chromatography. The H$_{3}$P0$_{3 }$ was found to be completely transferred into the aqueous layer. Complete return of benzotriazole to the butyraldehyde layer was also found. 

## Example 4 

## Example 5 

## Example 6 

