Abstract: Provided is a flexible circuit board. The flexible circuit board includes a circuit substrate; wherein the circuit substrate is a multilayer flexible circuit board, wherein at least two layers of the multilayer flexible circuit board include plated sublayers, and a plurality of grooves are disposed in a first surface of the multilayer flexible circuit board, a depth of the groove being not less than a depth of the plated sublayer closest to the first surface in the multilayer flexible circuit board.

Abstract: The present disclosure discloses a method for preparing 2,5-dimethylphenol by selective catalytic conversion of lignin, relates to the technical field of chemistry, and includes the following steps: mixing lignin, a catalyst, and ethanol, and then carrying out a catalytic conversion reaction of lignin under the gaseous supercritical conditions of ethanol; and cooling the reaction product by quenching after the completion of reaction, and then subjecting it to separation and extraction to obtain 2,5-dimethylphenol. The catalyst comprises a modified sepiolite carrier, an active metal Mo, and auxiliary agents Zr and Fe. The process of the present disclosure is simple, and the prepared catalyst is a solid catalyst, which avoids problems of difficult recovery, serious environmental pollution and equipment corrosion caused by the use of homogeneous organic acid-base catalysts.

Abstract: The present disclosure discloses a method for preparing 2,5-dimethylphenol by selective catalytic conversion of lignin, relates to the technical field of chemistry, and includes the following steps: mixing lignin, a catalyst, and ethanol, and then carrying out a catalytic conversion reaction of lignin under the gaseous supercritical conditions of ethanol; and cooling the reaction product by quenching after the completion of reaction, and then subjecting it to separation and extraction to obtain 2,5-dimethylphenol. The catalyst comprises a modified sepiolite carrier, an active metal Mo, and auxiliary agents Zr and Fe. The process of the present disclosure is simple, and the prepared catalyst is a solid catalyst, which avoids problems of difficult recovery, serious environmental pollution and equipment corrosion caused by the use of homogeneous organic acid-base catalysts.

Abstract: The present disclosure discloses a catalyst and a method for preparing 2-ethoxyphenol by catalytic depolymerization of lignin. The catalyst comprises sepiolite as a carrier and tungsten, nickel and molybdenum as active components supported on sepiolite. The catalyst for preparing 2-ethoxyphenol by catalytic depolymerization of lignin in the present disclosure can catalytically depolymerize lignin, realize the directional preparation of 2-ethoxyphenol from lignin, and co-produce lignin oil. It has a comparatively high selectivity for 2-ethoxyphenol and can achieve a lignin conversion rate of more than 95%, a 2-ethoxyphenol selectivity of more than 20% in a liquid product, and a yield of more than 100 mg/g of lignin.