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This work aims to evaluate waste marble dust in building industry therefore minimizing the environmental effects of waste dust and maximizing economic benefits with reducing the use of raw material and energy. The marble process industry generates a large amount of wastes during quarrying and sawing processes which pollute and damage the environment. There are many fields in which the marble wastes can be used, one of them is to use them in building industry. In this work, marble dusts provided from 3 different quarries, coming from 3 different places were coded as BN1, BN2 and BN3. After characterizing tests of the dust, they were used in the production of artificial marble tiles using a different amount of resin binder. By the respective physical, optical, chemical, and mechanical tests the maximum quantities that can be added have been determined. The results show that using 80 wt.-% marble dust and 20 wt.-% resin gives the best properties in tiles.

Large quantities of marble blocks are produced from many new marble quarries which were opened around Isparta (Turkey) and its surrounding region. The opened quarries are also affected negatively by weathering as a result of karstification. Therefore, block efficiency of the quarries is low which results in a lot of waste materials that can be used in cultured marble production. The production of artificial marble from marble waste materials around Isparta is the main purpose of the study. The cultured marble is an attractive, healthy and homogenous building material. It has a wide application in the building construction sector. Artificial marble which is composed of mineral dusts and polyesters has high mechanical strength and they are durable to various chemical and high temperature environmental conditions. Based on physico-mechanical properties, cultured marbles are accepted by Turkish Standards (TS). The materials used for the production of qualified cultured marble are directly related to the hardness of the minerals used as filler in the polyester resin. Physico-mechanical properties of cultured marble depend on the physical properties of the filler minerals. The compressive strength of the cultured marble material is controlled by the physical properties of the filler minerals, therefore, the hardness of the cultured marble is determined by the hardness of the filler mineral. The following analyses were carried out: wet unit volume analysis, dry unit volume analysis, compressive strength of the materials, capillary water absorption analysis, analysis of ultrasound velocity (P-wave) and the marble wastes bulk chemical analyses were investigated and the results of the data were evaluated and discussed. In addition, natural and artificial marbles were compared with respect to physico-mechanical properties.

Dye-sensitized solar cells (DSSCs) have been fabricated using a TiO2 paste composed of mixtures of 25 nm and 250 nm TiO2 particles at various ratios. A maximum energy conversion efficiency of 6.7% has been achieved using the DSSC, based on a TiO2 layer composed of 40 wt% 25 nm and 60 wt% 250 nm TiO2 particles. The short-circuit current density, open-circuit voltage, and filling factor of the cell were 12.95 mA, 0.82 V, and 0.63, respectively. The overall performance of the DSSCs based on TiO2 layers composed using a mixture of two different sized particles is much better than that of either only 25 nm or only 250 nm TiO2 particles. It is recognized that adding the larger particles to the small particles in the TiO2 paste increases the dye absorption and light scattering effects of DSSC, resulting in a higher short-circuit current density and improved energy conversion efficiency.

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