Milling acid process

Steeping and wet-milling processes are also utilized to separate soluble compounds from com. One process involves removal of soluble starch and protein from com by steeping com in a warm sulfurous acid solution for about one to two days. The undissolved com solids are then coarsely wet-milled and processed to collect the oil-containing germ for com oil production. Also, for more enzyme-resistant cellulose biomass, sulfuric acid or hydrochloric acid can be used to digest the cellulose polysaccharide into fermentable molecules. 

There are two major processes for the manufacture of titanium dioxide pigments, namely (1) sulfate route and (2) chloride route. In the sulfate process, the ore limonite, Fe0Ti02, is dissolved in sulfuric acid and the resultant solution is hydrolyzed by boiling to produce a hydrated oxide, while the iron remains in solution. The precipitated titanium hydrate is washed and leached free of soluble impurities. Controlled calcinations at about 1000°C produce pigmentary titanium dioxide of the correct crystal size distribution this material is then subjected to a finishing coating treatment and milling. The process flow sheet is shown in Fig. 7.1 [4],... 

Anotlier related processing byproduct, available in large quantities, is the unrecovered fiber disposed as paper mill sludge. This celiulosic feedstock is usually contaminated with various paper-making chemicals, such as clay and lime which would likely require separation before the cellulose could be used. However, processes are being developed that directly use the carbohydrate, including the levulinic acid process mentioned above. 

G. A. Mills (Houdry Process Corporation) Dr. Bond has considered that the catalytic reforming reactions occur at the atomic interface between metal and acid catalyst. It is possible that such reactions occur there and also possible that molecular hydrogen is activated by the metal and transferred to the acid as protons. However, I wish to point out that the metal-acid interface is not the necessary site for reforming reactions, as is shown by the following experiment carried out at the Houdry Laboratory. Pow-... 

The LCA process takes into account all of the energy, raw materials, water, and fossil fuels required in the production of Ingeo pellets. The first step is the harvesting of the corn in the fields where the corn is grown, harvested, dried, and transported to the com wet mill. The process requires fertilizers, electricity, fossil fuels, natural gas, and other materials. The second step is the production of starches and dextrose sugars with the use of fossil fuels, electricity, steam, water, and other materials. The third step is the fermentation to lactic acid with the use of electricity, fossil fuels, water, steam, and other materials. The fourth step is the production of lactide from lactic acid with the use of fossil fuels, electricity, steam, water, and other materials. The last step is the polymerization of polylactide and conversion into PLA pellets with the use of electricity, fossil fuels, water, and other materials. 

Natural style juices that contain the cloud are increasing in popularity, especiaHy apple juices, because these retain more fresh flavor if processed carefuUy. Optimum processing conditions chill the fmit to 4°C before milling, add 500 ppm ascorbic acid to retard browning, press under nitrogen, and flash pasteurize the juice as quickly as possible (4). 

Many methods for the conversion of acid copolymers to ionomers have been described by Du Pont (27,28). The chemistry involved is simple when cations such as sodium or potassium are involved, but conditions must be controlled to obtain uniform products. Solutions of sodium hydroxide or methoxide can be fed to the acid copolymer melt, using a high shear device such as a two-roU mill to achieve uniformity. AH volatile by-products are easily removed during the conversion, which is mn at about 150°C. A continuous process has been described, using two extmders, the first designed to plasticate the feed polymer and mix it rapidly with the metal compound, eg, zinc oxide, at 160°C (28). Acetic acid is pumped into the melt to function as an activator. Volatiles are removed in an extraction-extmder which follows the reactor-extmder, and the anhydrous melt emerges through a die-plate as strands which are cut into pellets. 

Lead Monoxide. Lead monoxide (litharge), PbO, occurs as a reddish alpha form, which is stable up to 489°C where it transforms to a yellow beta form (massicot). The latter is stable at high temperatures. The solubihty of a-PbO ia water is 0.0504 g/L at 25°C the solubihty of the p-PbO is 0.1065 g/L at 25°C (40). Lead monoxide is amphoteric and dissolves ia both acids and alkahes. In alkahes, it forms the plumbite ion PbO - The monoxide is produced commercially by the reaction of molten lead with air or oxygen ia a furnace. Black or gray oxide is manufactured by the Barton process, by the oxidation of atomized molten lead ia air, as well as by the ball mill process, ia which metallic lead balls of high purity are tumbled ia the mill to form partially oxidized lead particles. 

In order to make an efficient Y202 Eu ", it is necessary to start with weU-purifted yttrium and europium oxides or a weU-purifted coprecipitated oxide. Very small amounts of impurity ions, particularly other rare-earth ions, decrease the efficiency of this phosphor. Ce " is one of the most troublesome ions because it competes for the uv absorption and should be present at no more than about one part per million. Once purified, if not already coprecipitated, the oxides are dissolved in hydrochloric or nitric acid and then precipitated with oxaflc acid. This precipitate is then calcined, and fired at around 800°C to decompose the oxalate and form the oxide. EinaHy the oxide is fired usually in air at temperatures of 1500—1550°C in order to produce a good crystal stmcture and an efficient phosphor. This phosphor does not need to be further processed but may be milled for particle size control and/or screened to remove agglomerates which later show up as dark specks in the coating. 

---