Coarse filter

Manganese (II) acetylacetone [14024-58-9] M 253.2, m -250°. Purify by stirring 16g of reagent for a few min with lOOmL absolute EtOH and filter by suction as rapidly as possible through coarse filter paper. Sufficient EtOH is added to the filtrate to make up for the loss of EtOH and to redissolve any solid that separates. Water (15mL) is added to the filtrate and the solution is evapiorated with a stream of N2 until reduced to half its vol. Cool for a few min and filter off the yellow crystals, dry under a stream of N2, then in a... 

After A filter that is positioned after a coarse filter, to ensure that the air entering a space is at the required degree of cleanliness. 

Very small particles can be collected but large ones (above 5 pm) can cause arcing across the narrow gap between collector plates. A coarse filter should first remove these large particles. Precipitators are not normally suitable for wet environments since excessive moisture can cause electrical tracking and failure. Resistance to airflow is negligible. 

In many instances, the dichloromethane solution can be dried adequately by a simple filtration through coarse filter paper. 

In this case, a likely explanation for the apparent supersaturation is that the chemical analysis included not only dissolved aluminum and iron, but also a certain amount of aluminum and iron suspended in the water as colloids and fine sediments. Analytical error of this type occurs because the standard sampling procedure calls for passing the sample through a rather coarse filter of 0.45 tun p0re size and then adding acid to preserve it during transport and storage. 

FIGURE 13.3 Mobile phase reservoir, shown on the right, with vented cap and a coarse filter on the tip of the flow tube shown inside a well on the bottom of the reservoir. 

A guard column is a short, less-expensive liquid chromatography column that is placed ahead of the analytical column in an HPLC system. The purpose of a guard column is to adsorb and retain mixture components that would contaminate the more expensive analytical column. In-line filters are relatively coarse filters (compared to prefilters) placed in the mobile phase line to filter out particulates that maybe introduced on-line, such as from sample injection. 

Airborne particles, bacteria, fungi spores and allergens will be removed by air filtration, which is often cheaper and more effective than electrostatic precipitators and ionizers. A disposable, high-efficiency filter capable of removing at least 95 percent of particles with size down to 0.3 micron will be installed. A washable coarse filter that removes fifty percent of particles larger than 10 microns will be used as a pre-filter to extend the life of the high efficiency filter by at least a third. An inexpensive sensor will be included to indicate when filter replacement is necessary. 

The checkers found that the use of coarse filter paper and a Buchner funnel was preferable to a sintered glass funnel. 

Polypropylene powder was being conveyed by suction through a duct system as an air dispersion, fines being retained in a filter trap upstream of the centrifugal fans. However, the relatively coarse filter allowed very fine powder to pass and it was eventually retained over a long period of time in a silencer on the fan outlet. The thickening deposit eventually self-heated and ignited, and the fire spread very... 

Prefi1 ter Sect ion The prefilter system for the solvent was a pump and filter holder arrangement similar to that of the measurement system only using a coarse filter of 0.5 pm pores. 

The orange crystalline product is collected on a coarse filter and sucked as dry as possible. It is washed once with a 100-mL portion of 50 50 acetone-water. (Neat acetone causes dehyration.)... 

HC1 and heat to boiling. If the soln is not clear, filter a portion thru a coarse filter paper, heat ca 100 ml of the clear soln to boiling, and add slowly 10 ml of 50% sulfuric acid. A white ppt indicates barium, which can be confirmed by the grn color obtd in a flame test. Filter and add to the cool filtrate 1 ml of coned HC1. A white ppt indicates the presence of lead... 

Use of a ceramic Buchner funnel with coarse filter paper is recommended to avoid scraping a glass frit during removal of 1. A rubber spatula is recommended for stirring and manipulation of the filter cake. The filter cake can be conveniently removed from the funnel by applying a small amount of air pressure to the stem. 

At very low concentrations, c. 10 4 to 10 3 mol dm-3, the supersaturation is sufficient for extensive nucleation to occur, but crystal growth is limited by the availability of material, with the result that a sol is formed. At moderate concentrations, c. 10 2 to 10 1 mol dm 3, the extent of nucleation is not much greater, so that more material is available for crystal growth and a coarse filterable precipitate is formed. At very high concentrations, c. 2 to 3 mol dm-3, the high viscosity of the medium slows down the rate of crystal growth sufficiently to allow time for much more extensive nucleation and the formation of very many small particles. Owing to their... 

Herbage can be considered as a coarse filter interposed between atmosphere and ground. If a proportion p of the activity in fallout is intercepted by foliage, it is reasonable to write... 

Then steam was applied and the temperature was raised to boiling. 200 pounds of coarse filter aid (perlite) was added and the mixture filtered through a string discharge vacuum filter. The cake was washed with 200 gallons of hot water on the filter. 

If desired, the 2-hydrate can be purified by recrystallization. Sixteen grams of the dried material is stirred for a few minutes with 100 ml. of absolute ethanol, and the solution is then filtered with suction as rapidly as possible through coarse filter paper on a Buchner funnel. Sufficient ethanol is added to the filtrate to replace that lost by evaporation and to redissolve any solid which separates. Fifteen milliliters of water is added to the filtrate, and the solution is evaporated with a stream of nitrogen until reduced in volume by one-half. The mixture is then cooled for a few minutes. The yellow crystals are filtered off on a Buchner funnel and dried under the conditions specified for the unrecrystallized material. The yield is 30 to 50% of the quantity of unrecrystallized compound taken. Anal. Calcd. for Mn(C5Hv02)2-2H20 C, 41.5 H, 6.3 Mn, 19.0. Found C, 41.2 H, 6.1 Mn, 19.2. 

The checkers found that best results were obtained by centrifuging for 40 minutes and then filtering rapidly through a coarse filter, instead of filtering the thick suspension directly. In this way, the filtration is rapid and the removal of hydrated iron (III) oxide is complete. 

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