Specialty filters

Silasorb. [Cdite] Calcium silicate adsorbent, specialty filter aid. 

Your company manufactures specialty filters sketched below. The filter consists of an aluminum container packed with threads of polymer Q, The threads are coated with an active ingredient, chemical Z. The threads are approximately 1 mm diameter and 10 cm long and are wadded into entangled balls, which prevents the loss of any threads as fluid passes through the filter. The filters are produced by tamping a thread ball into an aluminum container open at one end, and then crimping the cap over the open end. 

R. A. Gross, Proceedings of the Specialty Conference on the User and Fabric Filter Equipment II, Air Pollution Control Association, Pittsburgh, Pa., 1975, pp. 159-163. 

The average prices of the batch centrifuge are shown in Fig. 18-154. All the models include the drive motor and control. In Fig. 18-154, the inverting filter, horizontal peeler, and the advanced vertical peeler are the premium baskets especially used for specialty chemicals and pharmaceuticals. Control versatility with the use of programmable logic control (PLC), automation, and cake-heel removal are the key features which are responsible for the higher price. The underdriven, top-driven, and pendulum baskets are less expensive with fewer features. 

Clean Air Machine Corp. Air purifiers - commercial site offers customized filters for specialty applications aimed at removal of microscopic particulates and gases. http //aco.ca/tibbits/index. html... 

Goodfcilow, H. D., R. J. Geren,, and E. F. C. Foord. Applications of Fabric Filters at High Air-to-Cloth Ratios on Metallurgical Fumes. In The User and Fabric Filtration F.qmpment 111, APCA Specialty Conference Proceedings, Buffalo, NY (Oct. 1-3, 1978). 

Commercial grades of PVP, K-15, K-30, K-90, and K-120 and the quaternized copolymer of vinylpyrrolidone and dimthylaminoethylmethacrylate (poly-VP/ DMAEMA) made by International Specialty Products (ISP) were used in this study. PEO standard calibration kits were purchased from Polymer Laboratories Ltd. (PL), American Polymer Standards Corporation (APSC), Polymer Standards Service (PSS), and Tosoh Corporation (TSK). In addition, two narrow NIST standards, 1923 and 1924, were used to evaluate commercial PEO standards. Deionized, filtered water, and high-performance liquid chromatography grade methanol purchased from Aldrich or Fischer Scientific were used in this study. Lithium nitrate (LiN03) from Aldrich was the salt added to the mobile phases to control for polyelectrolyte effects. 

These issues are really major ones in research laboratories dealing with specialty chemicals and first level scale-up. Filterability can be a problem with M catalysts supported on classic materials such as carbon, owing to their tendency to pulverisation to give nanometer-sized catalyst particles that turn out to be very difficult to be recovered and successfully reused. 

In addition to interference filters, NIR manufacturers use holographic gratings (moving and fixed), interferometers, polarization interferometers, diode arrays, acoustic-optic tunable filters, as well as some specialty types. 

Ciystallization from solution is an important separation and purification process in a wide variety of industries. These range from basic materials such as sucrose, sodium chloride and fertilizer chemicals to pharmaceuticals, catalysts and specialty chemicals. The major purpose of crystallization processes is the production of a pure product. In practice however, a number of additional product specifications are often made. They may include such properties as the ciystd size distribution (or average size), bulk density, filterability, slurry viscosity, and dry solids flow properties. These properties depend on the crystal size distribution and crystal shape. The goal of crystallization research therefore, is to develop theories and techniques to allow control of purity, size distribution and shape of crystals. 

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