Development of composite calcium hydroxide sorbent in mechanical operations and evaluation of its basic sorption properties

This article presents the results of research carried out on the possibility of obtaining composite calcium hydroxide sorbent in the process of two-step granulation, containing additional compounds of Al, Mg and Fe, and their textural and sorption studies. For this purpose, attempts were undertaken to compact commercial calcium hydroxide powder with six additives in the laboratory roll press. The resulting compacts were crushed and sieved in order to achieve the assumed sieve fraction. Based on the obtained results, basic parameters of the process of formation of composite sorbent have been determined. Both, the selected composite sorbents fractions and additives were subsequently subjected to textural studies (determination of the specific surface area and porosity) and sorption capacity performance. In addition, for the better interpretation of the results, thermogravimetric studies were carried out both for the additives and composite sorbents, as well as the grain size distribution of the additives. The results of the physicochemical tests of the obtained composite sorbents were compared with analogic results from the study on fine-grained hydroxide sorbent without additives and carbonate sorbent. The presented results showed that in a two-step granulation process it is possible to obtain the granular Ca(OH)2 sorbent, as well as composite sorbents possessing better SO2 sorption capacity in comparison to the powder Ca(OH)2 and/or to the calcium carbonate sorbent. This can be attributed to the combination of capability of the sorbent to appropriate thermal decomposition and the formation of a group of pores in the range of 0.07-0.3 microns

Physico-chemical properties of suspended solids from coal processing plant

The process of sedimentation is successfully used in various industries: from the food and chemical industry, through processing of natural minerals resources in the mining industry. The sedimentation process of suspensions depends on many factors, which mainly include the grain size and grain size distribution of the solid phase of the suspension and its chemical and phase composition. The aim of this work was to determine the basic physicochemical parameters of the suspended solids from coal processing plant for intensification of its sedimentation process by means of multiflux sedimentation and/or flocculation. The particle size (and/or particle size) distribution of solid phase of coal suspension was measured by laser diffractometer. Chemical composition was determined by ICP OES (Optical Emission Spectroscopy with inductively coupled plasma), and phase composition using X-ray diffraction. Both, the chemical composition and grain morphology were verified by SEM / EDS. As a result the shape and grain size distribution of tested suspension was determined as well as it was found that clay minerals such kaolinte and illite are next to quartz dominant constituents at its phase composition.SCOPUS: cp.pinfo:eu-repo/semantics/publishe

Surface area and porosity of nanotubes obtained from kaolin minerals of different structural order

Mesoporous materials with pore diameters in the range 2-50 nm forming tubular or fibrous structures are of great interest due to their unique properties. Because they are commonly used as sorbents and catalyst carriers, knowledge of their surface area and porosity is critical. A modified intercalation/ deintercalation method was used to increase the efficiency of nanotube formation from kaolin-group minerals which differ in terms of their degree of structural order. Unlike previous experiments, in the procedure adopted in the present study, methanol was used instead of 1,3-butanediol for grafting reactions and octadecylamine intercalation was also performed. The samples were examined using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). The specific surface area and porosity of previously described and newly formed materials were investigated by N adsorption/desorption. Compared to results described earlier, the percent yield of nanotubes obtained in the present study was significantly greater only in the case of 'Maria III' kaolinite, which has high structural order. This increase was obtained mainly by the grafting reaction with methanol. Highly ordered stacking of kaolinite-methanol intercalates was noticed and, thus, the amine intercalation was more efficient. In particular, the use of long-chain octadecylamine significantly increased the nanotube yield. The grafting reaction with methanol procedure yielded fewer nanotubes, however, when applied to poorly ordered samples ('Jaroszów' kaolinite and 'Dunino' halloysite). In the case of the 'Maria III' kaolinite, the diameter of the rolled layers observed by TEM was ~30 nm and corresponded to average diameters of newly formed pores (D N) determined using N adsorption/desorption, confirming that nanotubes contributed to an increase in surface area and total pore volume. In the case of 'Jaroszów' kaolinite and 'Dunino' halloysite mainly macropores (D N > 100 nm) and mesopores (20 nm > D N > 40 nm) were formed. The pores were attributed to interparticle and interaggregate spaces in the stacks of platy particles and to the small relative number of nanotubes

Changes in the Textural Parameters of Fly Ash-Derived Na-P1 Zeolite During Compaction Processes

This paper presents the possibility of receiving the granular forms of a zeolitic material of the Na-P1 type obtained from high-calcium fly ash in a semi-technical scale by means of three compacting techniques. The compaction process was carried out using cement, molasses and water glass as binders. Each of the proposed compacting methods affected the textural parameters of the obtained granular zeolite forms, as well as the binders used. In comparison to the other binders it was found that the cement binder had the smaller impact on the values of the textural parameters of the obtained compacted zeolite forms. The surface area for the zeolite Na-P1 was 98.49 m2•g-1, for the cement as a binder was 69.23 m2•g-1, for the molasses was 52.70 m2•g-1 and for the water glass was 40.87 m2•g-1. For this reason, the briquetting and extruding tests were carried out using cement as a binder