Nitric oxide oxidation, application surface effects

Reyad et al carried out surface modification of oil fly ash (OFA), a byproduct generated by oil power plants, by chemical treatment. A mixture of sulfuric and nitric acids was used to modify the surface in order to attach a carboxylic functional group to the surface of OFA. The goal of surface modification of OFA is to make its surface more compatible with non-polar polymers in order to produce OFA/polymer composite materials with improved dispersion of OFA, and to increase OFA surface area in order to support its use as adsorbent materials in adsorptive separation and purification applications. Different acid compositions were used in their study for the treatment by gradually increasing the nitric add concentration from 0 to 20%. They also examined the effect of oxidation on surface modification by introducing air to enhance the oxidation of OFA. 

Nitric oxide (NO), a diatomic free radical, naturally produced in the body by endothelial cells, is well known as an antithrombogenic mediator and its continuous release from the surface of endothelial cells effectively prevents the adhesion/activation of platelets on normal blood vessel walls. Hence, materials that release or generate NO locally at the surface to inhibit thrombus formation have been developed with great potential applications in blood-contacting medical devices with improved biocompatibility. 

On the other hands, it becomes obvious that SOx and NOx in flue gas can be removed at room temperature by using active carbon fibers (ACF) subjected to surface treatment such as heat treatment [1, 2], The flue gas treatment technology using ACF is a semidry oxidation type de-SOx method which is effective even around room temperature. In addition, this technology enables by-products such as sulfuric acid, sulfates, nitric acid, and various nitrates to be recovered, and is applicable in the field of flue gas treatment to which the conventional de-SOx method, such as the limestone gypsum method, could not be applied for economical reasons. 

---