Wetting industrial importance

This same technique should be helpful in understanding wetting properties important in the oil industry since wetting is very dependent on mineral surface energies. The use of contact angle hysteresis information may allow a better understanding of the effects of surface heterogeneities of natural mineral samples. The dynamic Wilhelmy plate technique is ideally suited for such experiments ... 

Introduction to the nature of colloids and the linkage between colloids and surface properties. The importance of size and surface area. Introduction to wetting and the industrial importance of surface modifications. 

Wet Classification Method. A second industrially important fiber-length evaluation technique is the Bauer-McNett (BMN) classification. 

The heterogeneous character of solid surfaces is a matter of the greatest importance to Chemistry, as it is on the exceptional state of strain in certain atoms in the surface that the catalytic properties of surfaces usually depend. This subject will be dealt with in Chapter VII in this chapter, those properties which can be averaged over considerable areas of the solid surface, such as their power of being wetted by liquids, will be considered. The average properties of solids are often of very great industrial importance. 

The industrial manufacture of aluminum hydroxide and aluminum oxide currently proceeds almost exclusively by the Bayer process i.e. by wet digestion of bauxite. The sinter- and melt-digestion processes with sodium carbonate and/or lime only have minor industrial importance. 

Wet Classification Method. A second industrially important fiber length evaluation technique is the Bauer-McNett (BMN) classification. In this method, a fiber slurry is circulated through a series of four grids with decreasing opening size (positioned vertically), thus yielding five fractions ( +4,... 

Accurate determination of elemental sulfur in petroleum and its distillates (petroleum products) is of significant industrial importance. It is being determined routinely by several techniques, for example, by the differential pulse polarography technique. The detection limit is 0.1 pg per g, but chemical treatment of the sample is needed. The wet chemical method of activated Raney nickel has been successfully employed with a detection limit of 0.1 pg per g. Also in this case preconcentration of sulfur is needed. By using the Houston Atlas sulfur analyzer in which... 

Apart from the widely used wet process for phosphoric acid (Chapter 5.2), several alternative processes for the extraction of P from its ores have been devised, although these have yet to become industrially important. 

Wetting is important in many processes, both industrial and natural. In many cases, wetting is a prerequisite for application ... 

Trickle-bed reactors, wherein gas and liquid reactants are contacted in a co-current down flow mode in the presence of heterogeneous catalysts, are used in a large number of industrial chemical processes. Being a multiphase catalytic reactor with complex hydrodynamics and mass transfer characteristics, the development of a generalized model for predicting the performance of such reactors is still a difficult task. However, due to its direct relevance to industrial-scale processes, several important aspects with respect to the influence of external and intraparticle mass transfer effects, partial wetting of catalyst particles and heat effects have been studied previously (Satterfield and Way (1972) Hanika et. al., (1975,1977,1981) Herskowitz and Mosseri (1983)). The previous work has mainly addressed the question of catalyst effectiveness under isothermal conditions and for simple kinetics. It is well known that most of the industrially important reactions represent complex reaction kinetics and very often multistep reactions. Very few attempts have been made on experimental verification of trickle-bed reactor models for multistep catalytic reactions in the previous work. 

It is interesting to consider the topic of this subsection from the perspective of the effects of the addition of Sn starting with pure Pb. The focus is on the industrially important ternary system Pb-Sn-Cu. Liu and Tu [165] studied the wetting of the Pb-Sn alloy system on Cu with both molten alloy and solid substrate immersed in RMS flux. The experiments were conducted at 10°C... 

Wet-Process Phosphoric Acid. As indicated in Figure 7, over 95% of the phosphate fertilizer used in the United States is made by processes that require an initial conversion of all or part of the phosphate ore to phosphoric acid. On a worldwide basis also, the proportion of phosphate fertilizer made with phosphoric acid is very high. Thus processes for production of phosphoric acid are of great importance to the fertilizer industry (see PHOSPHORIC ACID AND THE PHOSPHATES). 

There are numerous variations of the wet process, but all involve an initial step in which the ore is solubilized in sulfuric acid, or, in a few special instances, in some other acid. Because of this requirement for sulfuric acid, it is obvious that sulfur is a raw material of considerable importance to the fertilizer industry. The acid—rock reaction results in formation of phosphoric acid and the precipitation of calcium sulfate. The second principal step in the wet processes is filtration to separate the phosphoric acid from the precipitated calcium sulfate. Wet-process phosphoric acid (WPA) is much less pure than electric furnace acid, but for most fertilizer production the impurities, such as iron, aluminum, and magnesium, are not objectionable and actually contribute to improved physical condition of the finished fertilizer (35). Impurities also furnish some micronutrient fertilizer elements. 

Most carbide acetylene processes are wet processes from which hydrated lime, Ca(OH)2, is a by-product. The hydrated lime slurry is allowed to settle in a pond or tank after which the supernatant lime-water can be decanted and reused in the generator. Federal, state, and local legislation restrict the methods of storage and disposal of carbide lime hydrate and it has become increasingly important to find consumers for the by-product. The thickened hydrated lime is marketed for industrial wastewater treatment, neutrali2ation of spent pickling acids, as a soil conditioner in road constmction, and in the production of sand-lime bricks. 

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