Utilization of marine waste for the sustainable synthesis of triple superphosphate, dicalcium phosphate, and gypsum: Exploration of crystallographic parameters using XRD data

Abstract

The dwindling reserves of essential raw materials used in synthesizing three industrially valuable materials, triple superphosphate (TSP), dicalcium phosphate dihydrate (DCPD), and gypsum, emphasize the need for sustainable and environment-friendly methods. In the current work, attempts have been undertaken to synthesize these vital compounds via typical wet precipitation methods from marine debris (Ficus gracilis (F.gracilis), Mauritia Arabica (M.arabica), and Trochus orchroleucus (T.orchroleucus)), which are an abundant and easily accessible source of calcium. Afterward, employing X-ray Diffraction (XRD) analysis, the produced triple superphosphate, dicalcium phosphate dihydrate, and gypsum were characterized. A wide range of crystallographic parameters were evaluated, including crystallite size, dislocation density, crystallinity index, microstrain, specific surface area, preference growth, and texture coefficient. Alongside this, different models were used to calculate the crystallite size of synthesized crystals. Among these models, the Williamson–Hall model yielded the most appropriate results for crystallite size, which was determined to be in the approximate range of 47.81–277.30 nm. The preference growth calculation showed a thermodynamically favorable preference along (020), (021), and (010) planes for triple superphosphate, (020), (021), and (041) planes for dicalcium phosphate dihydrate and (020), (040), and (041) planes for gypsum. The results from the texture coefficient showed texturing along (020), (-120) planes for triple superphosphate (021), (020) planes for dicalcium phosphate dihydrate, and (020), (040) planes for gypsum. The similar texturing values of the same compounds indicate the crystal planes' development with aligned planes.