Porous vaterite and cubic calcite aggregated calcium carbonate obtained from steamed ammonia liquid waste for Cu2+ heavy metal ions removal by adsorption process

Infrared-Light-Responsive Controlled-Release Pesticide Using Hollow Carbon Microspheres@Polyethylene Glycol/α-Cyclodextrin Gel

“…The structural evolution of HCMs/IMI/PEG/α-CD was investigated by XRD (Figure a). The spectrum of CaCO 3 microspheres showed distinct peaks at 24.87°, 27.03°, 32.7°, and 39.39° (trace i), indicating that CaCO 3 was mainly composed of calcite and vaterite, according to the standard profiles by Joint Committee on Powder Diffraction Standards (JCPDS) card numbers 72-0506 and 81-2027 . In contrast to the crystalline structure of CaCO 3 microspheres, the HCMs only showed a broad peak of amorphous carbon (trace ii), confirming the complete removal of CaCO 3 and the carbonization of polydopamine.…”

“…The spectrum of CaCO 3 microspheres showed distinct peaks at 24.87°, 27.03°, 32.7°, and 39.39°(trace i), indicating that CaCO 3 was mainly composed of calcite and vaterite, according to the standard profiles by Joint Committee on Powder Diffraction Standards (JCPDS) card numbers 72-0506 and 81-2027. 24 In contrast to the crystalline structure of CaCO 3 microspheres, the HCMs only showed a broad peak of amorphous carbon (trace ii), confirming the complete removal of CaCO 3 and the carbonization of polydopamine. As for the pesticide system (trace iii), the peaks at 11.92°and 14.29°could be ascribed to α-CD 25 and the peaks at 19.89°and 22.80°corresponded to PEG 6000, 26 which suggested the functionalization of HCMs/ IMI by the PEG/α-CD pair.…”

Sonochemical Synthesis of Vaterite-Type Calcium Carbonate Using Steamed Ammonia Liquid Waste without Additives

“…When the ultrasonic amplitude is increased, the agglomeration degree of the products reduces to a certain extent. From Figures and , it can be seen that the vaterite aggregates produced using the ultrasonic method are inconsistent with those obtained by the author in relevant studies. − Therefore, it can be concluded that the ultrasonic method can prevent vaterite agglomeration.…”

“…This method can realize single metastable spherical vaterite CaCO 3 . Our previous research studies − have shown that preparing single-purity metastable vaterite CaCO 3 through conventional simple mechanical mixing using steamed ammonia liquid waste as the calcium source is difficult. In addition, several reported studies have also indicated that achieving single-phase high-purity vaterite CaCO 3 without additives − is difficult even when using the ultrasonic chemistry method .…”

Zn2+ removal from the aqueous environment using a polydopamine/hydroxyapatite/Fe3O4 magnetic composite under ultrasonic waves

“…5 Heavy metals nd application in various industrial sectors, such as the metal plating, electroplating, mining, leather, and fertilizer industries, and, as a consequence, every year directly or indirectly a large number of these pollutants, mainly zinc, copper, nickel, arsenic, lead, cadmium, chromium, mercury, and cobalt, enter the environment through industrial wastewater discharge. [6][7][8] It has been demonstrated that toxic metals can enter the human body through food chains and their accumulation has been linked to the onset of various diseases and illnesses such as neurological disorders, various cancers, imbalances in hormones, obesity, abortion, asthma, infertility, and death. 9 The zinc ion is one of the most employed metals in the industrial eld.…”