CN-122010143-A - Preparation method of electronic grade ammonium fluoride solution

CN122010143ACN 122010143 ACN122010143 ACN 122010143ACN-122010143-A

Abstract

The invention belongs to the field of chemical industry, and particularly relates to a preparation method of an electronic grade ammonium fluoride solution. The method comprises the steps of taking a solid ammonia source and hydrogen fluoride as solid phase raw materials and gas phase raw materials respectively, taking the solid ammonia source as carrier gas, mixing the carrier gas and the hydrogen fluoride gas to form reaction gas, heating, introducing the reaction gas into the reaction vessel to contact the solid ammonia source for temperature control solid-gas contact reaction, monitoring the temperature of the reaction vessel in the reaction process, stopping introducing the hydrogen fluoride until the reaction vessel starts to be cooled, continuing to introduce the carrier gas, stopping and recycling the solid phase product after continuous cooling, and preparing the obtained solid phase product into the electronic grade ammonium fluoride solution with the target concentration according to requirements. The invention adopts a novel solid-gas contact thermal reaction method, thereby effectively reducing the preparation difficulty and equipment requirements of the electronic grade ammonium fluoride solution, facilitating the operation, and simultaneously having higher safety in the preparation process and higher utilization rate of raw materials.

Inventors

PAN MEIHUA
DONG JUNQING
WANG YUANCHAO
ZHU BOCHAO
ZOU JUNWEI
Jin Chaoshuai
Wang Hangshuai
TANG YICHENG
ZHAO XUN

Assignees

浙江森田新材料有限公司

Dates

Publication Date: 20260512
Application Date: 20251030

Claims (7)

1. A preparation method of electronic grade ammonium fluoride solution is characterized in that, The method comprises the following steps: solid ammonia source and hydrogen fluoride are respectively used as solid phase raw materials and gas phase raw materials, the solid ammonia source is placed in a reaction container, inert gas is used as carrier gas, the carrier gas and hydrogen fluoride gas are mixed to form reaction gas, and after the reaction gas is heated, the reaction gas is introduced into the reaction container to contact the solid ammonia source for temperature control solid-gas contact reaction; Monitoring the temperature of a reaction container in the reaction process, stopping introducing hydrogen fluoride and continuously introducing carrier gas after the reaction container starts to be cooled, stopping and recovering a solid-phase product after the reaction container is cooled to be only 2-3 ℃ higher than the temperature of the reaction gas; And (3) recycling the obtained solid-phase product to prepare the electronic grade ammonium fluoride solution with the target concentration according to the requirement.
2. The method for preparing an electronic grade ammonium fluoride solution according to claim 1, wherein, The solid ammonia source is ammonium carbamate.
3. The method for preparing an electronic grade ammonium fluoride solution according to claim 1, wherein, The hydrogen fluoride gas is prepared by evaporation of industrial hydrofluoric acid.
4. A process for preparing an electronic grade ammonium fluoride solution according to claim 1, 2 or 3, The inert gas is nitrogen and/or argon.
5. The method for preparing an electronic grade ammonium fluoride solution according to claim 4, wherein, And heating the reaction gas to 36-38 ℃.
6. The method for preparing an electronic grade ammonium fluoride solution according to claim 1, wherein, The carrier gas and the hydrogen fluoride gas are mixed according to the volume ratio of (6-10): 1 to form the reaction gas.
7. The method for preparing an electronic grade ammonium fluoride solution according to claim 1 or 6, wherein the flow rate of the hydrogen fluoride gas in the reaction gas is controlled to be 0.02-0.05 mol.min-1.mol-1 solid ammonia source.

Description

Preparation method of electronic grade ammonium fluoride solution Technical Field The invention belongs to the field of chemical industry, and particularly relates to a preparation method of an electronic grade ammonium fluoride solution. Background Ammonium fluoride (NH 4 F) is a common and commonly used chemical raw material, which is commonly used in the fields of mineral dressing, electroplating industry, glass time, iron and steel industry, organic synthesis, agriculture and other fields, and has very wide application. In the electronics industry, the purity requirements of ammonium fluoride used in semiconductor manufacturing are extremely high, often requiring electronic grade standards to be met, and the impurity levels, particularly the metal ion and particulate impurities, need to be tightly controlled at very low levels. Also, electronic grade ammonium fluoride solutions have very stringent requirements for metal ion and particulate impurity levels, such as levels typically up to ppm for metal ion impurity levels. At present, the technology capable of realizing the preparation of ammonium fluoride or ammonium fluoride solution mainly comprises a gas phase method and a liquid phase method. The gas phase method has the advantages of high reaction rate, high product purity, capability of reaching electronic grade standards and the like, but has strict reaction conditions, extremely high requirements on equipment, requirements on temperature control, pressure control and the like, and high cost and poor safety of high-purity hydrogen fluoride gas. However, the liquid phase method has the advantages of simple operation, economy, safety and the like, but has low purity, requires multi-step impurity treatment, and is generally difficult to reach the electronic grade standard. In addition, the above gas phase method and liquid phase method have a major disadvantage in that the raw material utilization rate is low, the recovered raw material is difficult to recycle (the purity is lowered and cannot meet the raw material standard requirement), and the excessive raw material is easy to form impurities which are difficult to remove. Other common processes such as fluorosilicic acid process, ammonium chloride/sodium fluoride heating sublimation process, etc. have more or less disadvantages. In this regard, it is very important to develop a synthetic route which is more environmentally friendly and simple and easy to implement. Disclosure of Invention The invention provides a preparation method of an electronic grade ammonium fluoride solution, which aims to solve the problems that the existing ammonium fluoride and ammonium fluoride solution synthesis process is relatively fixed, and the preparation of an electronic grade ammonium fluoride solution product is generally difficult to realize, or the preparation difficulty is relatively high, the safety is relatively poor, the raw material utilization rate is low and the like. The main purpose of the invention is that: 1. the preparation difficulty and the equipment requirement of the electronic grade ammonium fluoride solution can be effectively reduced; 2. The safety of the preparation process is improved; 3. Greatly reduces the requirements of partial raw materials and improves the utilization rate of the raw materials. In order to achieve the above purpose, the present invention adopts the following technical scheme. A method for preparing electronic grade ammonium fluoride solution, The method comprises the following steps: solid ammonia source and hydrogen fluoride are respectively used as solid phase raw materials and gas phase raw materials, the solid ammonia source is placed in a reaction container, inert gas is used as carrier gas, the carrier gas and hydrogen fluoride gas are mixed to form reaction gas, and after the reaction gas is heated, the reaction gas is introduced into the reaction container to contact the solid ammonia source for temperature control solid-gas contact reaction; Monitoring the temperature of a reaction container in the reaction process, stopping introducing hydrogen fluoride and continuously introducing carrier gas after the reaction container starts to be cooled, stopping and recovering a solid-phase product after the reaction container is cooled to be only 2-3 ℃ higher than the temperature of the reaction gas; And (3) recycling the obtained solid-phase product to prepare the electronic grade ammonium fluoride solution with the target concentration according to the requirement. As a preferred alternative to this, The solid ammonia source is ammonium carbamate. As a preferred alternative to this, The hydrogen fluoride gas is prepared by evaporation of industrial hydrofluoric acid. As a preferred alternative to this, The inert gas is nitrogen and/or argon. As a preferred alternative to this, And heating the reaction gas to 36-38 ℃. As a preferred alternative to this, The carrier gas and the hydrogen fluoride gas are mixed accordi