Document vV3KRMe1r08bORb54kpkQZz4Y

(conoopj Interoffice Communication To P.L. Fetzer From Date Subject H.L. Hackett February 8, 1972 Progress Report, January 1972 Oxygenates in Tars Ethyl Corporation has recently suspended purchase of our tars be cause of high oxygenate levels. Oxygenated compounds having OH, Cs=0, or COOH groups lead to trichloroacetyl chloride in their perchloroethylene product. They have observed trichloroacetyl chloride levels up to 3000 ppm vhen using CONOCO tars as part of their feed stock. They consider 250 ppm as the maximum permissible level of this difficult-to-remove contaminant. Qualitative infra-red analyses of our tars showed appreciable OH and C=0 absorption. No OH or C=0 absorption was found in a sample of Ethyl Corporation's tars. Tars from Shell in Deer Park, Texas (Stauffer's Licensee) had somewhat higher OH but lower C=0 absorp tion than ours. l.R. analyses of several of our plant streams were obtained. Qualitative results are tabulated below with the absorp tion levels found in the EDC tar still bottoms ranked as "high". EDC TS Bottoms(1-5-72) VC TS Bottoms(1-5-72) EDC TS Overhead(l-6-72) C-203 Vinyl Tower Bottoms(1-6-72) S-309 Oxy EDC(" -6-72) Heavy Ends Fead(l-28-72) Heavy Ends Bottoms(l"6-72) EDC TS Pumpout(5-11-72) EDC TS Pumpout(7-71, during test) EDC TS Pumpout(9-14-71) OH High Nil High Nil High Trace High High Very High High C=0 High Low Low Nil Low Trace Med High Med High Several treatment schemes have been attempted for removal of oxygenates from EDC TS Bottoms with poor to moderate success. 1. Bauxite Treatment: The first bed volume of EDC TS Bottoms showed greatly reduced OH and C=0 but the bauxite rapidly became loaded. CCR 000033909 2. Extraction With 2% Caustic: One-minute extraction of EDC TS Bottoms vith an equal volume of 2% sodium hydroxide solutions at room temperature cut the carbonyl absorption to less than half. The two phases did not split readily and the OH band was covered up by water even though an attempt was made to dry the sample. 3. Treatment With Concentrated Sulfuric Acid: one volume of 98% sulfuric acid was stirred vigorously with 10 volumes of EDC. TS Bottoms for 30 minutes at room temperature. The treated tars (8.4 volumes) were separated by decantation from the black viscous sludge. The treated tars were washed with 2% sodium hydroxide (no emulsion problem) and then with water. A small portion was dried over anhydrous sodium sulfate. The carbonyl absorption was reduced to less than 40% and the alcoholic OH was almost gone. There was OH absorption due to water at nearly the original alcoholic OH level. Water is also detri mental to Ethyl's process and therefore, must be removed if used in any treatment scheme. Tretolite AP5518 is added to C-103 heavy ends column to reduce foul ing. This material has significant carbonyl absorption and was cal culated to be present in our tars at a level of 3282 ppm. Laboratory disillation of C-103 feed (no additive and very little OH and C=0 absorption) with 99% overhead gave a bottoms spectra very similar to the EDC Tar Still Bottoms. It is concluded that the additive can only be a minor contributor to the oxygenates in our tars. Emulsion in T~102 Caustic Wash Several attempts were made to "break" this emulsion which is very troublesome although it has not resulted in EDC loss. Filtration through a bed of filter-aid readily gave two clear liquid phases with very little cuff between them. A sand bed filter gave almost the same results although the two layers were hazy with a small cuff between them. There was a thin layer of dark brown "tar" left on the top of both beds. Both readily re-emulsified on shaking. The following specific gravity measurments were made on the layers in T"102 caustic wash vessel when the emulsion was especially bad. Chloride analyses were obtained to check the level of dissolved sod ium chloride. 1100 Hrs. 1-14-72 Specific Gravity Chloride at Room Temp Meq/Ml P-102 Caustic Wash Pump, Aqueous phase T-102 Caustic Wash Vessel, Emulsion P-102 Caustic Wash Pump, EDC Phase 1330 Hrs. 1-14-72 1.054 1.20 1.247 .31 P-102 Aqueous Phase T-102 Emulsion P-102 EDC Phase 1.050 1.17 1.242 34 CCR 000033910 Heating the emulsion even to the boiling point of EDC was not effective in breaking the emulsion. A sample of the emulsion has been submitted to R&D, Ponca City, for identification of the agent(s) responsible. Their results are expected soon. Solids from the Vinyl Distillation Column Large black chunks of solid washed from the vinyl column in December were submitted to the laboratory. These chunks did not dissolve or break apart in refluxing EDC or boiling water. Addition of caustic to the water also failed to disperse them. No alternatives to manual cleaning has been found for removal of this type of material from the vinyl column. Homer L. Hackett Manufacturing Chemist bs cc: LNV -DOP -RDG"RHG -JDM-FK CCR 0000339II