Preparation and properties of water dispersible ramie stalk cake

In order to investigate the feasibility for the industry application of ramie stalk in treating heavy metal waste water, the microcosmic characterizations of ramie stalk particles were conducted by characterization methods such as laser particle size analyzer, SEM and FTIR etc. firstly, and the microstructure of ramie stalk was ascertained. Then based on those, water dispersible ramie stalk cake (WDRSC) were processed by mixing the ramie stalk particles with the environmental friendly natural wetting agent, adhesive and disintegrating agent according to a certain technological process. During the screen process of formula, the influences for the mass fractions of various additives on properties of WDRSC were tested, and the abilities of ramie stalk and WDRSC for adsorption of heavy metal Cu²⁺ and Cd²⁺ were compared. The results show that ramie stalk is a natural substance with porous structure, and a large number of adsorption sites and groups are related to the surface. When the mass ratio of ramie stalk, wetting agent, binder and disintegration agent in WDRSC formula is 75∶13∶2∶10, WDRSC can quickly be wetted (wetting time is less than 60 s) by water and automatic disintegration (disintegration time is less than 60 s) as soon as it touches water, the suspension rate within 60 s reaches about 80%, and the properties are all in accordance with the requirements of water dispersible granules. The related properties of WDRSC were affected by wetting agent, binder and disintegrating agent at different degrees. Comparing with ramie stalk, the removal rates of WDRSC for Cd²⁺ and Cu²⁺ improve 11% and 4% respectively. The conclusions obtained indicating that manufacturing ramie stalk into WDRSC has advantages such as convenient transportation and application, low costing, easy manufacturing process and convenient waste residue treatment after adsorption etc., which is a feasible method for the large-scale utilization for ramie stalk.