Process development during

In addition to the comparison of different stages of process development during scale up, the evaluation of alternative syntheses or processes using mass indices and environmental factors or LCA may reveal the lack of resource efficiency and thus call into question the current mode of operation. Decisions that were made in earlier stages of scale-up may then be revised. 

Continuous Methods for Manufacturing Nitrocellulose. Several methods are known, of which the Dietzsch process developed during WWII in Germany is briefly described here under Combustible and Consumable Cartridge Cases. This method combines vapor-phase and liquid-phase nitration processes. The Japanese used during WWII a continuous liquid-phase method of nitration of paper pulp, which was in the form of a sheet... 

This process gave yields up to 80% based on the formaldehyde used. It was used at the Kriimmel plant of Dynamit AG until an expin in Jan 1943 completely destroyed th e plant E-Verfahren (E-Process). This process, developed during 1935 38 by Drs Erbele Fischer of Dynamit AG, is based on the reaction of paraformaldehyde with AN, dissolved in acetic anhydride. There-suiting Hexogen is separated, washed with water, stabilized dried. The product has a mp of only 190 95° and is obtd in yields of 60 75% based on paraformaldehyde. It contains the same impurities, but in larger amts, as found in the KA-Verfahren (process) described below... 

The high-viscosity processes developed during and after the pioneering period and the applications discovered for high-viscosity machines [8] are as striking as they are varied. 

Natural gas displaced most manufactured gas for municipal distribution in industrialized countries after World War II. In the 1960s and 1970s, interest in developing advanced coal gasification processes was rekindled when it was believed that natural gas reserves would become insufficient in a few years to meet demand. This activity has since declined, but several coal gasification processes developed during this period have been commercialized and are used for production of fuel and synthesis gas. 

The process developed during the course of this work is simple, direct, and efficient. It is capable of wide application to processing of tar sands in Utah, Canada, and perhaps other deposits. Moreover, the concept of using heat pipes is of even broader applicability in the process industries in general and... 

The industrial applications of catalytic processes have been generally in advance of theoretical knowledge of the mechanisms involved. Most of the catalytic processes developed during the 19th century and the early decades of the 20th century were the results of cut-and-try methods inspired by what Hilditch6 has called chemical intuition. Even today, many industrial catalytic processes are still guided by empiricism. 

Linear polyethylenes are produced in solution, slurry, and increasingly, gas-phase low-pressure processes. The Phillips process developed during the mid 1950s used supported chromium trioxide catalysts in a continuous slurry process (or particle-form process) carried out in loop reactors. Earlier, Standard Oil of Indiana patented a process using a supported molybdenum oxide catalyst. The polyethylenes made by both these processes are HDPE with densities of 0.950-0.965 g/cm and they are linear with very few side-chain branches and have a high degree of crystallinity. 

W.A. Carr, Saturn S-II Materials and Processes Development during the First Half of 1968, Report No. SID-63-600-10, Rockwell International Space Division, Downey, California (1968). 

Many natural fibers have been used by mankind for generations. Semi-synthetic f. are based on mainly cellulose and modified by processes developed during the last ISO years. 

---