Gas Discharge Synthesis - C&EN Global Enterprise (ACS Publications)

Nov 5, 2010 - ... is now ready for use on a commercial scale, according to Lord Mfg., ... strength of electric field, residence time, temperature, and...
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• O t h e r Pastures. While maintain­ ing its interest i n t h e subcommittee on p u m p s , t h e M T C h a s also been a t work examining other «chemical process equipment for standardization. T w o fields h a v e shiowrn promise—heat exchangers and process tanks. Accord­ ing to Peter Jandrisevits o f Merck, some $3 million annually might b e saved through adoption of standards for t h e of t a n k s used a t pressures MCA's Mechanical Technical Committee speaks f o r manufacture less than 15 p.s.i.g. This saving would chemical industry in A S A projects result from a reduction in fabrication costs a n d engineerintg lioie. jandrise­ vits expects his committee will soon ardization of centrifugal p u m p s for recommend that a ta_nk standardization υ NTTL RECENTLY» the chemical indus­ try h a s paid scant attention t o t h e about a year a n d a half. This project project b e started. standardization of its equipment. T h e was oringinally sponsored jointly b y T h e heat exchanger subcommittee, reasons for this are many, b u t t h e d a y MCA a n d t h e Hydraulic Institute. h e a d e d by A. H . ICnolL of Procter & has come w h e n t h e cost of not stand­ W h e n M T C w a s formed, it undertook Gamble, has found that development ardizing makes it imperative that t h e to represent t h e chemical industry in of standards specific t o thie needs of the this ASA subcommittee ( formally titled chemical industry rnighut lead t o a n industry do something. So says D . C. Brand of Monsanto. Sectional Committee B-73). estimated annual savings also in this $ 3 • P r o g r e s s Report. This committee million range. And, h e continues, something certainly This committee will ( B-73 ) m a d e its first progress report to make its recommenditLons to MCA is being done. F o r t h e past several years, the industry h a s been working t h e chemical industry at t h e 1 9 5 6 early next year. toward representation in American Chemical Exposition in Cleveland. J. Brand, Boyer, Jandrisevits, and Knoll Standards Association a n d toward d e ­ R. Boyer, chairman, described how t h e participated in a symposium on stand­ work h a d been carried out a n d sum­ veloping haison between t h e ASA a n d ardization at t h e Craemical Exposition marized the accomplishments of t h e in Cleveland. T h e symposium chair­ the chemical process industry. T h e first step i n this direction w a s committee and t h e work yet to b e done. man w a s J. G. Henderson. T h e job h a d been divided into four the formation, as p a r t of ASA, of t h e Chemical Industry Correlating Com­ major categories: mittee in 1950. This group was formed • Develop t h e optimum number of to make recommendations t o t h e p u m p sizes to handle the capacity Gas Discharge Synthesis proper committees in ASA concerning range from 5 to 1000 gal. p e r m i n . standards projects. T h e committee Work out standard foundry dimensions, Luminous high frequency dis­ was later renamed Chemical Industry and base plate and shaft dimensions. charge gives high activation Advisory Board ( C I A B ) . • Develop uniform dimensions in t h e a t lower temperatures However, there w a s still no group specifically to sponsor standards proj­ stuffing box area. • Develop a list of essential a n d d e ­ ects i n ASA and to determine t h e needs of the chemical industry as these sirable features to b e incorporated into C^#HEMICAL SYNTHESIS i n a discharge gas is now ready for use on a commer­ projects developed. Therefore, Manu­ the standards. facturing Chemists' Association formed, • Develop uniform definitions, letter cial scale, according t o Lord Mfg., Erie, in January 1956, t h e Mechanical Tech­ designations, and coding of spare parts. Pa. I n this process, gas p h a s e reactions are earned out i n a luminous high fre­ nical Committee to fill these needs. T h e second and fourth portions of quency electrical discharge. So now t h e chemical industry h a s T h e most significant aspect of this the machinery to sponsor standardiza­ this work are now essentially complete, Boyer says. T h e group a t work on t h e process, t h e company says, is that it tion projects in ASA a n d to maintain third part, developing desirable fea­ produces activated reactant states a t liaison between itself and ASA. ASA has been working on stand­ tures, has compiled 10 features agreed temperatures lower than, are normally upon by all interested parties. obtained by converttional methods of However, this group has found diffi­ activation. This means -that some syn­ culty with one apparently simple item: theses requiring higli levels of activa­ ASA Sectional Committee B-73, "Should t h e discharge nozzle b e in t h e tion m a y become practical. An added in t h e course of its w o r k on stand­ center or at a tangent?" All polls to plus is that some thermally unstable ardization of single stage, end suc­ date h a v e resulted in about 50-50 splits materials can b e recovered because of tion, centrifugal p u m p s , found of opinion, Boyer says. reduced processing temperatures. s o m e 128,000 different units in T h e first subgroup has not yet use across t h e country. For mate­ • W h a t It Is. A gas ixnder t h e influ­ finished its work. So far, it has found ence of a n electrical field will break rials of construction, t h e figures that t h e r e are about 128,000 different down into ions, free radicals, a n d acti­ show: centrifugal p u m p s with capacities b e ­ vated molecules; these reactive mate­ Material Percentage tween 5 a n d 1000 gal. p e r min. After rials will recombine witht each other t o 29% Cast iron examining t h e statistics, t h e group feels form products different from t h e origi­ 15% Steel it can cut this to eight sizes. However, nal gas. T h e exact products formed 47% Stainless steel it h a s not y e t settled upon t h e exact are functions of pressure, strength of 2% H i g h silicon iron sizes for each of t h e eight. electric field, residence t i m e , tempera­ 7% Others T h e committee expects to complete ture, and geometry of the reaction zone. A n d , more than half of these pumps its work and make final recommenda­ The process, developed by A. L . are rated for less than 100 gal. per tions to ASA by the end of 1957, Rouy of t h e Lord organization, works xnin. a t less than 100 ft. of head. Boyer concluded. best in t h e pressure range of 10 to 5 0

PRODUCTION

Manaaras — ι ne n o w a n a ι ne W h a t

6232

C&EN

DEC.

17, 1 9 5 6

"Locked in the Versene claw"—thafs thefa£e of metal ions when they encounter chelating agents. They become trapped within the inwer ring structure of a newly formed compound where they cannot hinder processing or mar product quality. This phrase is taking on new meaning for many industries* as the chemistry of chelation is reviewed.

T h e Chemistry of Chelation: Part IV Applications

in specific industries

· Synthetic rubber

manufacture

Soaps and synthetic detergents * Textile processing * A new kind of chemistry? As has been discussed previously, the Versene® series and Versenol® series chelating agents will inactivate practi­ cally all metal ions t h e y contact in solution. The pH of the solution or of the finished product influences the choice of agent. To control iron in caustic solutions, look to Versene T®; in alkaline solutions—Versene Fe-3 Specific®: i n acid solutions—the Ver­ sene® series- Or if solutions drift from one pH value to another, an effective Versene combination can be devised to completely complex metal ions present. However, when it is desirable, the claw-like holding power of chelation can be reversed. In polymerization re­ actions, for example, ferrous iron ions can be released gradually at a pre­ determined rate. SYNTHETIC RUBBER MANUFACTURE

Erratic polymerization has been a costly bottleneck in producing syn­ thetic rubber. Now, research has dis­ closed that this situation can be corrected by means of a reproducible redox catalyst activation system using Versene Fe-3 alone or with pyrophos­ phate. A blend of ethylenediaminetetraacetic acid and N, N-di-(2-hydroxyethyl) glycine sodium salt, Versene Fe-3 has proved adequate at less than 1 / 1 0 0 of a part per 100 parts of mono­ mer. The complexing action of Versene Fe-3 locks large reservoirs of ferrous ions in the chelated form and releases them gradually, allowing polymeriza­ tion to continue at a controlled rate for

a longer period. Results: Uniform con­ trol of trace metal catalysts is assured; plant operations smooth out; product nonuniformities practically disappear. SOAPS A N D SYNTHETIC DETERGENTS

It should be re-emphasized that a judicious choice of chelating agent must be exercised for a particular application. If the right Versene or Versene combination is properly used in a detergent formulation, process­ ing is improved, exceptional watersoftening and detergent properties are realized. For unlike dehydrated phos­ phates, which lose effectiveness in alkaline media and at high tempera­ tures, the Versene remains stable; is many times more effective; and can be used in formulating all types of soaps and synthetics—liquid, bar, powdered, or flake. It is a simple matter, for example, t o include Versene in liquid soaps. Here, the chelation action pro­ vides the same clarity with hard water as can be achieved with distilled or rain water. Also, the soap comes out lighter colored and protected against rancidity and change of color. W h e n the soap is stored in glass, Versene inhibits silica deposition. Or consider solid detergents. Versene makes possible a bar soap that can resist water of 10 grains hardness! pH is an important factor. Versene 9 is recommended, since large amounts may be added without changing the pH of the product.

you can depend

on DOW

TEXTILE PROCESSING

The textile industry is using chelation to advantage too . . . in kier boil and bleach operations . . . to produce softer, stronger fabrics that take dye better. For, in complexing metal ions, chelation results in a new compound that cannot be precipitated by common agents. In kier boiling operations, Versene Τ inactivates iron and other metal ions which discolor the cloth, and removes rust and corrosion deposits from the processing equipment. Often a larger amount of Versene Τ may be necessary due to the rust build-up in the system. Later, the amount is reduced and equipment remains clean, thus making possible cleaning and bleaching of the fabric producing high-quality goods through metal ion control. A N E W K I N D OF CHEMISTRY?

Is chelation the answer to all ion con­ tamination difficulties? Despite its many successful applications, the an­ swer is sometimes "no". For, remark­ able as it is—in locking up metal ions to improve production and product quality—chelation does not solve all problems in every application. But wherever metal ions do pose a problem, investigation is worthwhile. And we'll help in every possible way. To see if you can put the Versene or Versenol products to profitable use, write Tech­ nical Service and Development, Dept. SC914A-2. T H E DOW CHEMICAL COM­

PANY, Midland, Michigan.

CHEMICALS DEC.

MGm 17,

1956

C&EN

6233

PRODUCTION

TWO HOUDRY CATALYSTS THAT INCREASE ΑΑΤ1ΙΙΓ

U lil H Ht

AT LOW COST Houdry Mineral Kaolin— f o r catalytic

cracking

This new, improved, pelleted natural cracking catalyst for Houdriflow and TCC Moving Bed Catalytic Cracking Units offers maximum octane at low­ est cost. Among the many features it provides are: High Activity—Sulphur Re­ sistance—Superior Thermal Stability—Excellent Regenerability—Maximum Octane —Low Cost. Houdry Type 3-D Platinum — f o r catalytic

reformnig

This improved, pelleted plati­ num catalyst employed for catalytic reforming operation increases octane number and selectivity, and offers increased activity and stability at a low cost particularly interesting to refiners. Houdry will manufacture pel­ leted type catalysts to specifi­ cation, and will assist you in developing catalysts for special requirements. Write for additional information.

F&

Pione&r in Catalysis

H - " ; 1528*Walnut Street, Philadelphia 2, Pa.'./ î

6234

C&EN

DEC. 17.

1956

Aries Polyethylene More details on the new low pressure polyethylene process developed hy R. S. Aries & Associates were released by Robert S. Aries, president, in Paris during the XXIX International Con­ gress of Industrial Chemistry.

v Roger, Wilco For materials handling in large, sprawling plants, two-way radio offers interesting possibilities. Rohm and Haas found its service was improved, waste morion was reduced, and material transfer costs w e r e cut b y some $12,000 per year w h e n RCA two-way radios were installed at its 60-Bcre Bristol, Pa., plant.

£400,000 At A Time In a modern application of an old principle, Lederle Laboratories uses these stainless steel coating pans to apply final color and wax coats to pharmaceutical tablets. Each rotating pan holds 400,000 pills. According to Aries, his organization has been working on polyolefins over the past four years, with work being done both in the U. S. and affiliated laboratories in Europe. The resulting process, covered by some dozen patent applications, is completely outside of Ziegler and Phillips patents, Aries says. Aries declines to describe his catalyst in detail. However, i n contrast to aluminum alkyl, which must always be kept in sealed containers, the catalyst is not flammable in air, Aries says. In addition, he points out, only a very slight trace of ash remains in the polyethylene. Reported properties of Aries AA type polyethylene (several different types have been developed, according to Aries) are: Oensity 0.945-0.960 Annealed 0.954-0.965 Cold Pressed Tensile Strength P. s. i., 25° C. 3500-4000 900-1175 P. s. i., 100° C. Brittleness temperature - 1 0 5 ° C. 80% nonfailure Oielectric Constant 2.38 50 mc at 25° C. Ash trace Unsaturation (IR) Terminal (% C = C ) Pendant methylene Carbonyl (% C = O )

III

IK PROCESS CORPORATION ;

mm. of mercury and at a frequency of 27 megacycles. Gas temperatures from —73° to 100 e C. have been studied. In contrast to previous similar gas discharge processes, this one has zones of controlled and interrelated pressure, temperature, and residence time. It is in these zones that activation, reaction, and product removal are carried out, Rouy says. Discharge gap, area, and composition of the surface material in contact with the discharge are most im­ portant. • Some Uses. Lord has found that hydrides, halides, and nitrides of the lighter elements— potential high energy fuels—can be synthesized directly. D e ­ composition of ammonia to form hydra­ zine, studied at length, shows a conver­ sion efficiency of nearly 2% by weight, the company has found. The process may have other uses, too. For example, it is believed the process can produce rare compounds such as subhalides of boron and phos­ phorus, high oxidation states of nitro­ gen and sulfur, carbon fluorine com­ pounds, and trapped free radicals and activated complexes.

T r i o A A o r r o r l o TIÇIÇ T>oor» T-vrr\r1nr»ia/1

large scale pilot plant runs.

ir\

PRODUCTION

TWO HOUDRY CATALYSTS THAT INCREASE ΑΑΤ1ΙΙΓ

U lil H Ht

AT LOW COST Houdry Mineral Kaolin— f o r catalytic

cracking

This new, improved, pelleted natural cracking catalyst for Houdriflow and TCC Moving Bed Catalytic Cracking Units offers maximum octane at low­ est cost. Among the many features it provides are: High Activity—Sulphur Re­ sistance—Superior Thermal Stability—Excellent Regenerability—Maximum Octane —Low Cost. Houdry Type 3-D Platinum — f o r catalytic

reformnig

This improved, pelleted plati­ num catalyst employed for catalytic reforming operation increases octane number and selectivity, and offers increased activity and stability at a low cost particularly interesting to refiners. Houdry will manufacture pel­ leted type catalysts to specifi­ cation, and will assist you in developing catalysts for special requirements. Write for additional information.

F&

Pione&r in Catalysis

H - " ; 1528*Walnut Street, Philadelphia 2, Pa.'./ î

6234

C&EN

DEC. 17.

1956

Aries Polyethylene More details on the new low pressure polyethylene process developed hy R. S. Aries & Associates were released by Robert S. Aries, president, in Paris during the XXIX International Con­ gress of Industrial Chemistry.

v Roger, Wilco For materials handling in large, sprawling plants, two-way radio offers interesting possibilities. Rohm and Haas found its service was improved, waste morion was reduced, and material transfer costs w e r e cut b y some $12,000 per year w h e n RCA two-way radios were installed at its 60-Bcre Bristol, Pa., plant.

£400,000 At A Time In a modern application of an old principle, Lederle Laboratories uses these stainless steel coating pans to apply final color and wax coats to pharmaceutical tablets. Each rotating pan holds 400,000 pills. According to Aries, his organization has been working on polyolefins over the past four years, with work being done both in the U. S. and affiliated laboratories in Europe. The resulting process, covered by some dozen patent applications, is completely outside of Ziegler and Phillips patents, Aries says. Aries declines to describe his catalyst in detail. However, i n contrast to aluminum alkyl, which must always be kept in sealed containers, the catalyst is not flammable in air, Aries says. In addition, he points out, only a very slight trace of ash remains in the polyethylene. Reported properties of Aries AA type polyethylene (several different types have been developed, according to Aries) are: Oensity 0.945-0.960 Annealed 0.954-0.965 Cold Pressed Tensile Strength P. s. i., 25° C. 3500-4000 900-1175 P. s. i., 100° C. Brittleness temperature - 1 0 5 ° C. 80% nonfailure Oielectric Constant 2.38 50 mc at 25° C. Ash trace Unsaturation (IR) Terminal (% C = C ) Pendant methylene Carbonyl (% C = O )

III

IK PROCESS CORPORATION ;

mm. of mercury and at a frequency of 27 megacycles. Gas temperatures from —73° to 100 e C. have been studied. In contrast to previous similar gas discharge processes, this one has zones of controlled and interrelated pressure, temperature, and residence time. It is in these zones that activation, reaction, and product removal are carried out, Rouy says. Discharge gap, area, and composition of the surface material in contact with the discharge are most im­ portant. • Some Uses. Lord has found that hydrides, halides, and nitrides of the lighter elements— potential high energy fuels—can be synthesized directly. D e ­ composition of ammonia to form hydra­ zine, studied at length, shows a conver­ sion efficiency of nearly 2% by weight, the company has found. The process may have other uses, too. For example, it is believed the process can produce rare compounds such as subhalides of boron and phos­ phorus, high oxidation states of nitro­ gen and sulfur, carbon fluorine com­ pounds, and trapped free radicals and activated complexes.

T r i o A A o r r o r l o TIÇIÇ T>oor» T-vrr\r1nr»ia/1

large scale pilot plant runs.

ir\