Preparation of potassium sulfate and zeolite NaA from K-feldspar by a novel hydrothermal process

Synthesis of KAlSiO4 by Hydrothermal Processing on Biotite Syenite and Dissolution Reaction Kinetics

“…Compared to microcline, two kinds of KAlSiO 4 obtained here are easier to be decomposed in the acid soil, which not only can supply potassium nutrition to plants but can ameliorate the soil with the porous structure. Although some large-pore potassium-rich zeolites such as L-types, A-types, and F-types can be prepared from the aluminosilicate residues or fusion products of K-feldspar, their treatment processings are complicated [27,29]. The synthesis of two types of KAlSiO 4 was simpler and just involved one step, which fits with the green chemical production.…”

“…In our previous study, the dissolution products of potassic rocks were investigated in different solutions to prepare potassic salts. Most of them focus on optimizing hydrothermal treatment techniques of potassic rocks in order to realize the maximum utilization of resources and clean production [29,30]. The reaction rate plays a key role in influencing the efficiency of preparation techniques and dissolution process.…”

Hydrothermal reaction of K‐feldspar powder in NaOHCa (OH)2 mixed medium

“…in China since 1993. Generally, hydrothermal treatment is a promising step for K‐feldspar ore processing …”

“…Generally, hydrothermal treatment is a promising step for K-feldspar ore processing. 8,11,12 Engineering of K-feldspar ore requires the entire destruction of K-feldspar structure, leaving potassium as exactable K + into solution. As K 2 O only possesses 16.9 wt.% in K-feldspar, process on this mineral should both consider the chemical behavior of K 2 O and the rest SiO 2 and Al 2 O 3 components, that is, their comprehensive utilization.…”

Purification and rapid dissolution of potassium sulfate in aqueous solutions

“…[1][2][3][4][5] Potash fertilizers used in agriculture usually contain two types: one is potassium chloride (KCl), which is harmful to some crops, increases soil salinity and pH of the soil, and the other is potassium sulfate (K 2 SO 4 ), which is a chlorine-free, high-quality, potent potash fertilizer, especially indispensable for tobacco, tea, potatoes, watermelon, sugar beets and other economic crops that are sensitive to chlorine. [6][7][8][9] Fully water-soluble potassium sulfate can dissolve rapidly and completely in water, allowing it to be more efficiently absorbed and utilized by crops. More importantly, K 2 SO 4 can be applied in agricultural facilities for processes such as sprinkler irrigation and drip irrigation.…”