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Animal and Municipal Organic Wastes and Water Quality
Published in R. Lal, B. A. Stewart, Soil Processes and Water Quality, 2020
Treatment of manure with monocalcium phosphate before spreading reduced ammonia losses from field-applied material by 17% (Gordon et al., 1988). Monocalcium phosphate produces dicalcium phosphate and phosphoric acid (Lindsay and Stephenson, 1959) and thereby reduces the pH value of the amended manure.
Biological Process for Butanol Production
Published in Jay J. Cheng, Biomass to Renewable Energy Processes, 2017
Maurycy Daroch, Jian-Hang Zhu, Fangxiao Yang
Historically, molasses was the most widely used raw material for ABE fermentation. Molasses, a by-product of sugar mill, is the mother liquor after sugar crystallization in the process of sugar refining. Sugar cane and sugar beet are typical feedstocks for sugar production in tropical and temperate climates, respectively. As a by-product of sugar mill, molasses is also reasonable in cost when compared to other feedstocks. Its other properties are also highly advantageous for fermentation; most notably, molasses requires very little pre-treatment prior to fermentation. In most cases dilution and removal of insoluble solids is sufficient. Some saccharolytic microorganisms are capable of fermenting molasses directly and producing very high yields of the solvents. Molasses contains sugars (50%–70%), inorganic salts (some of them are added to aid in the recovery of crystalline sucrose), and vitamins, which makes it an excellent raw material for fermentation (Mitchell, 1998). Generally, molasses is inadequate in nitrogen and phosphorus. Therefore, these nutrients need to be added into the medium for efficient fermentation. In industrial production, ammonia is commonly used to adjust the pH value and as a nitrogen source. Superphosphate (monocalcium phosphate, Ca(H2PO4)2) and P2O5 are usually added as phosphorus sources.
Recent Developments in Materials Innovation for Bone Tissue Regeneration
Published in Gilson Khang, Handbook of Intelligent Scaffolds for Tissue Engineering and Regenerative Medicine, 2017
Swapan Kumar Sarakar, Byong-Taek Leea
One of the key issues with bioceramic bone substitutes is their ability to bear load in a limited scale while the healing is occurring in the defect site. However, ceramics are historically regarded as non-load-bearing materials and bioceramics like HAp, tricalcium phosphate (TCP), and other calcium phosphate–based materials (calcium sulfate, dicalcium phosphate, monocalcium phosphate, etc.) are brittle and not of high strength. Introduction of porosity significantly decrease the bulk strength as well. However, as a high degree of porosity is indispensable for a sound osteointegration, methods are devolved to modify the microstructure and other structural features of the porous bioceramics to attain higher strength. Processing conditions and methods can drastically alter the surface characteristic of the fabricated bioceramics scaffold and thus pave the way for a high-strength scaffold. Block-type (as shown in Fig. 4.1), cylindrical-granule-type (as shown in Fig. 4.2), and spherical-granule-type bone substitutes have been reported using the sponge replica process (Fig. 4.1), fibrous monolithic process (Fig. 4.2), and slurry-dripping process.38,39,40,41
A novel and sustainable approach for biotransformation of phosphogypsum to calcium carbonate using urease producing Lysinibacillus sphaericus strain GUMP2
Published in Environmental Technology, 2023
Prajakta Pratap Patil, Meghanath Prabhu, Srikanth Mutnuri
This economic process generates a large quantity of PG 5 tons of PG is generated for every ton of phosphoric acid production [3,4]. The worldwide generation of PG is estimated to be around 100–280 MT.yr−1 [5,6]. PG is mainly composed of calcium sulfate or gypsum (CaSO4.2H2O) and contains impurities such as phosphoric acid, calcium phosphate, monocalcium phosphate, dicalcium phosphate, residual acids, fluorides (NaF, Na3AlF6, Na2SiF6, Na3FeF6, and CaF2), sulfate ions. PG also contains trace metals (e.g. Cu, Cr, Zn, and Cd) and organic matter adhered to the surface of gypsum crystals, as aliphatic compounds of carbonic acids, amines, and ketones [7,8]. This low-cost by-product (usually regarded as waste) is commonly used in agriculture as a fertilizer and soil stabilizer and utilized for commercial applications, such as gypsum board production and Portland cement [9–11]. Nevertheless, such practices are limited due to the high content of toxic substances for human health, and only 15% of the worldwide PG production is recycled. The remaining 85% requires huge storage or disposal area and causes health and environmental problems viz. contamination of soil, surface and groundwater, and atmospheric contamination [12,13]. Radioactive elements are the primary concern regarding the storage of PG and have an adverse environmental impact. As a result, environmental organizations such as the USEPA have imposed numerous limitations on using this residue for any purpose [3].