Document jm3mY5VVVMgrK8ONoQQpVQgrR

engineering / YEAR AFTER YEAR IT OUTPERFORMS ALL OTHERS. The Chemical Week i Buyers' Guide is the most-used in its field. In 1973 and 1974 major research studies were conducted to determine the buying actions of Buyers' Guide users. Conclusion: advertising generates actual pur chase orders. | Want to do your own study? We'll help. I Call Joe Callahan, j Buyers' Guide Manager, at 212/997-2379. THt NEWS M*OA2lN FOA PROCESS MANAGEMENT Chemical Week ^ 1221 AvenutctlhtAmBfKas. Hew York,NY 10020 36 CHEMICAL WEEK MARCH 24, 1976 ever, the new membrane has not been as efficient electrically as asbestos dia phragms. "The trouble is that the Nafion mem brane permits more hydroxyl ions to mi grate from the cathode compartment into the anode compartment Every time that happens, you lose an electron," says John M Watkins, venture specialist m Du Pont's Plastic Products and Resms Dept Ftndmg methods of cutting down that migration is the atm of much of the cur rent development work. Du Pont, Dia mond Shamrock, Hooker and several Japanese companies are hard at work on the improvements. Diamond isn't talking about the modi fications it has made, but the firm does say it will produce high-strength caustic with minimal salt concentration directly m the electrolyzer at high current effi ciencies at its Muscle Shoals installation. The new membrane will be used in con junction with DSA anodes. (DSA is Electronor Corp's trademark for dimen sionally stable anodes) Hooker's Currey explains that power consumption is strongly affected by cur rent density And depending on the den sity, either the membrane or the dia phragm cell can be shown to be more efficient. In the amperage ranges now being considered for commercial equip ment, the asbestos diaphragm unit has some advantages m power consumption. For example, Hooker's MX cell con sumes 2,800 kwh /short ton of chlorine, compared with a typical asbestos dia phragm cell's consumption of 2,500 kwh. Asahi Glass, which became the first Japanese chlonne-causiic producer to switch from mercury cells to diaphragm units, m March 1974, believes it is ahead of other firms in that country in its re search effort. Its interim reports on its new membrane indicate chlorine and caustic quality is comparable to that made in mercury cells. Moreover, Asalu Glass says the process will prove econom ically competitive because there is no need for evaporation. Asahi Glass test data show that current efficiency is between 90 and 92% with caustic soda concentrations of 40-41%. The company says the technique can be applied to potash production as well, with current efficiencies of 90-96%, prod uct concentration of 40-41% and 10-20 ppm of potassium chloride in the prod uct. Building Plans: AM Japanese producers have research programs going at top speed to meet the government deadline for switching to dtaphragm cells Most are building test installations to compare their own membranes with Du Pont's. For example. 'Iokuynma has n 3.000metne-tons/year test operation at Tokuyama City for comparing tls membrane with Nafion. Toyo Soda hopes to build a 2,000m t / month plant at Sakata City, Honshu, by spnng 1977, using Hooker technology. Meanwhile, it is testing its own mem brane as well as Du Pont's at a pilot plant in Shtn-Nanyo City, Honshu. Asaht Chemical Industry built a 40.000- m t./ycar plant at Nobeoka, Kyushu, last Apnl to test the Nafion membrane. It also has been developing its own membrane And the company says us plant can be expanded to 100,000 m t /year by adding cells, The Nation membrane also will go to work tn a 60,000-m t /year untt that Denkt Kagnku Kogyo is building at its Omi works, Honshu, under licensing agreement from Asahi Chemical And Asahi Glass plans to replace its 5.000- m.t/month plant at Osaka City with its new membrane. Its 1,400m.t./month plant completed in March 1974 at Kita Kyushu on Kyushu Island, uses diaphragm-cell technology supplied by Diamond. Last fall, it started up new units, each of 15,000 m.t./month, at Kashima and Chiba, near Tokyo, using PPG technology. Automatic VCM sampler A new idea in monitoring vinyl chlo ride monomer emissions has been put to work at Pantasote's Passaic, N J, plant, Pantasote and Eocom Corp. (Irvine, Calif.), developers of the system, say it is much faster than gas chromatograph sampling systems ordinarily used. The new system, which combines a mini-computer and a Fourier multiplex spectrometer, can assess the quality of air at a specific sampling point once each minute. Plant personnel are alerted when instantaneous exposure is above pre scribed Occupational Safety and Health Administration limits. Pantasote and Eocom, which are offer ing the system to others, say it has a pay out time of about two years because it eliminates charcoal-tube personnel sam plers. The systems, installed at Pantasote's two Passaic plants, cost about $350,000 for 48 sampling points The computer program uses plant physical features, properties of airborne vmyl chloride monomer and work profiles to automati cally determine employee exposures. RSV0033730