Extraction of nano-scale CaCO3 technology for papermaking from waste
Abstract: Nano-CaCO3 fillers have been successfully prepared from waste marble powder and natural limestone by wet carbonization technology. Anions (sodium oleate) and cationic surfactants (CTAB) were used to modify the size, morphology, and surface properties of the nano-CaCO3 filler. Compared with GCC, the filler is kept high and the paper strength is unchanged. The degree of wear of the filler is determined by the particle structure of the filler, the purity of the particles, and the hardness of the particles. The challenge of using commercial grade nanofillers is low retention and high cost of ownership. However, nano-CaCO3 fillers overcome these challenges because the raw materials from which they are prepared are readily available and are simple to manufacture and low in production cost. Nano-sized precipitated CaCO3 fillers have been used in many industries due to their excellent performance, and the market demand is already large. However, there is little information on the application of nanoprecipitated CaCO3 fillers in papermaking. In order to improve the use of inexpensive nano-CaCO3 fillers in papermaking, anionic surfactants (sodium oleate) and cationic surfactants (CTAB) were used to explore the modification effect. The choice of sodium oleate and CTAB is based on low cost and low toxicity. Two impure CaO materials, namely waste marble powder and natural limestone, were calcined at 1000 ° C for 2 h. Each calcined CaO was aged in a reaction system of Ca(OH)2-H2O-CO2 in distilled water at 80 °C. After the ripening, the lime milk was cooled to room temperature (20 ° C), and then the CO 2 gas was introduced into the milk from the bottom of the conical flask and vigorously stirred. The pH of the reaction solution and the conductivity were measured online by a pH meter and a conductivity meter. When the pH reached 9 and the conductivity dropped sharply, the reaction was completed. The addition of CO 2 gas was stopped, the suspension was washed with distilled water/ethanol, filtered, and then dried in a drying oven at 120 ° C for 24 hours to obtain CaCO 3 filler particles. Sodium oleate (anionic surfactant) and CTAB (cationic surfactant) are separately added to the solution during the preparation of the CaCO3 filler to complete the modification. The prepared CaCO3 filler particles were added to the slurry in an amount of 15% (relative to dry fiber) compared to unfilled and commercial GCC filled paper. In the preparation of nano-CaCO3 fillers, the addition of surfactants reduces the size of the particles and changes the morphology of the particles (triangular to diamond). Used in papermaking, the retention of the filler is improved and the optical properties of the paper are greatly improved. The results demonstrate that the use of waste marble powder to produce CaCO3 fillers is a good route to eliminate the negative impact of waste marble on the environment. (Source: Network, copyright belongs to author) Electric Eyebrow Trimmer,Lipstick Eyebrow Trimmer,Usb Rechargeable Hair Remove,Echargeable Lipstick Eyebrow Razors ZHEJIANG SHENGFA ELECTRIC APPLIAMNCES CO.,LTD , https://www.shengfa-appliance.com