A process for recovery of lithium ions from a lithium-bearing brine, the process comprising: contacting the lithium-bearing brine with a lithium ion adsorbent based on orthosilicate. The lithium ion adsorbent is a de-lithiated form of: Li.sub.2X.sub.1-y-zY.sub.yZ.sub.zSiO.sub.4, where y and z together=0 to 1 and X, Y and Z are each Fe, Mg, Ca, Ni, Mn, Co, Zn, Cu, Ti, V, Sr or Zr.

Provided is a method of preparing a superabsorbent polymer. More particularly, provided is a method of preparing a superabsorbent polymer, the method capable of preparing the superabsorbent polymer maintaining excellent basic absorption performances such as centrifugal retention capacity, absorbency under load, etc. while also exhibiting an improved absorption rate.

The present invention provides that powder is mainly constituted from secondary particles of hydroxyapatite. The secondary particles are obtained by drying a slurry containing primary particles of hydroxyapatite and aggregates thereof and granulating the primary particles and the aggregates. A bulk density of the powder is 0.65 g/mL or more and a specific surface area of the secondary particles is 70 m.sup.2/g or more. The powder of the present invention has high strength and is capable of exhibiting superior adsorption capability when it is used for an adsorbent an adsorption apparatus has.

The present disclosure provides a desulfurization and sulfur recovery method for sulfur dioxide flue gas, and belongs to the technical field of non-ferrous metal smelting. The method includes the following steps: desulfurizing the sulfur dioxide flue gas by taking slagging flux limestone or quicklime for smelting or converting process as a desulfurizer, and adsorbing SO.sub.2 in the gas to obtain gypsum residue, calcium sulfite, and the desulfurized flue gas, where SO.sub.2 in the sulfur dioxide flue gas before desulfurization is less than 1 vol %; and recycling the gypsum residue and the calcium sulfite to the smelting or converting furnace for slagging, resolving the SO.sub.2 into smelting off-gas, producing sulfuric acid in acid plant.

A method of using a pelletized composition for liquid solidification and moisture retention includes the steps of: Providing a pelletized absorption material having i) at least 60% by weight agricultural fibers; and ii) 0.1-20% by weight superabsorbent polymer, wherein the pellets are substantially uniform and have a density of less than 40 LBS/Cubic Foot; and Blending the pelletized absorption material with one of i) Sludge, ii) Landfill leachate; iii) material used in hydroseeding; iv) grass seeds, fertilizer, and/or mulch to form a soil amendment; v) settling pond; and vi) wastewater streams.

The present application relates generally to filter media useful for manufacturing air filters for residential and commercial office's Heating, Ventilation, and Air Conditioning (HVAC), particularly to filters and filter media comprising soybean-based materials. The present invention provides an inexpensive, effective, environmentally friendly, and sustainable media for manufacturing HVAC air filters for residential and commercial buildings.

A method of treating wood chips to be used as a media for ameliorating oil spills on land or water involves heating in a mixture of petroleum wax and vegetable oil to remove moisture content and open the pores of the wood chip to allow the oil/wax blend to penetrate into the interior of the wood chips and subsequently grinding up the chips to a predetermined mesh size. The ground chips impregnated with wax/oil are then blended with magnetic iron ore concentrate and packaged/bagged for later distribution on an oil slick. The magnetic iron ore concentrate clings to the ground, oil/wax coated wood chips and facilitates retrieving the ground chips that have absorbed the spilled oil using a magnetic pick-up.

A silver-doped, nano-porous hydroxyapatite material is provided that can be utilized to capture radioactive iodine, .sup.129I. Methods of using the silver-doped, nano-porous hydroxyapatite material to remove radioactive iodine, and methods of manufacturing the material are also provided.

A method for preparing a nano carbon dioxide agent and an application of the agent are disclosed. The method takes cationic surfactant modified bentonite as a carrier, and the CO.sub.2 nano agent prepared by loading cationic surfactant modified chitosan, graphene oxide and organic alkali modified hydrotalcite has the photocatalytic effect of nano materials, which can enhance photosynthesis, increase photosynthetic rate, inhibit light respiration at night, synthesize chlorophyll for crop growth, accumulate three essential elements of carbon, hydrogen and oxygen for crop growth, effectively absorb, synthesize and transform organic components such as nitrogen, phosphorus and potassium in soil, fully promote the gestation, growth and maturity of crops, and increases production and income. The CO.sub.2 capture agent of the disclosure can be used for both facility crops and field crops, and the CO2 capture agent under normal temperature and pressure has wide application.

[Problem] In an embodiment involving addition of a chelating agent in an upstream process of the process for production, such as the polymerization step, the residual ratio of the chelating agent in the final product, a particulate water-absorbing agent, is improved.

[Solution] A particulate water-absorbing agent having a poly(meth)acrylic acid (salt)-based water-absorbing resin as a main component, containing a chelating agent having a nitrogen atom and an inorganic reducing agent having a sulfur atom, wherein the particulate water-absorbing agent has a chelating agent ratio of 0.8 to 1.8, as calculated by the following procedures (a) to (c): (a) subjecting the particulate water-absorbing agent to a predetermined impact test; (b) sieving the particulate water-absorbing agent subjected to the impact test into a particle group 1 with a particle size of less than 300 μm and a particle group 2 with a particle size of 300 μm or more and less than 850 μm using a JIS standard sieve; and (c) quantifying a content C1 of the chelating agent present in the particle group 1 and a content C2 of the chelating agent present in the particle group 2, and then dividing the C1 by the C2.