The present invention relates to a process for the production of a zeolitic material having an MWW framework structure comprising YO.sub.2 and B.sub.2O.sub.3, wherein Y stands for a tetravalent element, said process comprising (i) preparing a mixture comprising one or more sources for YO.sub.2, one or more sources for B.sub.2O.sub.3, one or more organotemplates, and seed crystals, (ii) crystallizing the mixture obtained in (i) for obtaining a layered precursor of the MWW framework structure, (iii) calcining the layered precursor obtained in (ii) for obtaining the zeolitic material having an MWW framework structure, wherein the one or more organotemplates have the formula (I)

R.sup.1R.sup.2R.sup.3N   (I) wherein R.sup.1 is (C.sub.5-C.sub.8)cycloalkyl, and wherein R.sup.2 and R.sup.3 are independently from each other H or alkyl, and wherein the mixture prepared in (i) and crystallized in (ii) contains 35 wt.-% or less of H.sub.2O based on 100 wt.-% of YO.sub.2 contained in the mixture prepared in (i) and crystallized in (ii), as well as to a synthetic boron-containing zeolite which is obtainable and/or obtained according to the inventive process and to its use.

Described herein is a process for producing a zeolitic material having an MWW framework structure containing YO.sub.2 and B.sub.2O.sub.3, in which Y stands for a tetravalent element. The process includes the steps of (i) preparing a mixture containing one or more sources for YO.sub.2, one or more sources for B.sub.2O.sub.3, one or more organotemplates, and seed crystals, (ii) crystallizing the mixture obtained in (i) for obtaining a layered precursor of the MWW framework structure, and (iii) calcining the layered precursor obtained in (ii) for obtaining the zeolitic material having an MWW framework structure. Also disclosed herein are synthetic boron-containing zeolites obtain by the process and uses thereof.

Described herein is a process for producing a zeolitic material having an MWW framework structure containing YO.sub.2 and B.sub.2O.sub.3, in which Y stands for a tetravalent element. The process includes the steps of (i) preparing a mixture containing one or more sources for YO.sub.2, one or more sources for B.sub.2O.sub.3, one or more organotemplates, and seed crystals, (ii) crystallizing the mixture obtained in (i) for obtaining a layered precursor of the MWW framework structure, and (iii) calcining the layered precursor obtained in (ii) for obtaining the zeolitic material having an MWW framework structure. Also disclosed herein are synthetic boron-containing zeolites obtain by the process and uses thereof.

The present disclosure provides a sound absorbing material. The sound absorbing material comprises MFI-structural-type zeolite. The MFI-structural-type zeolite comprises a framework, and the framework comprises SiO.sub.2 and AlO.sub.3, and the mass ratio of Si to Al in the framework is less than 200 and not less than 50. The present disclosure also provides a speaker box applying the sound absorbing material. The sound absorbing material provided by the present disclosure and the speaker box using the sound absorbing material can further improve the performance of the speaker box, reduce the failure of zeolite and improve the performance stability of the speaker box.

The invention relates to a molecular sieve SCM-14, a preparation process and use thereof. The molecular sieve has a schematic chemical composition of a formula of “SiO.sub.2.1/nGeO.sub.2” or a formula of “kF.mQ.SiO.sub.2.1/nGeO.sub.2.pH.sub.2O”, wherein the molar ratio of silicon to germanium, n, satisfies n≤30, and other values and symbols are defined in the specification. The molecular sieve has unique XRD diffraction data and can be used as an adsorbent or a catalyst.

The invention relates to a molecular sieve SCM-14, a preparation process and use thereof. The molecular sieve has a schematic chemical composition of a formula of “SiO.sub.2.1/nGeO.sub.2” or a formula of “kF.mQ.SiO.sub.2.1/nGeO.sub.2.pH.sub.2O”, wherein the molar ratio of silicon to germanium, n, satisfies n≤30, and other values and symbols are defined in the specification. The molecular sieve has unique XRD diffraction data and can be used as an adsorbent or a catalyst.

A continuous process for preparing a zeolitic material comprising (i) preparing a mixture comprising a source of YO.sub.2, optionally a source of X.sub.2O.sub.3, and a liquid solvent system; (ii) continuously feeding the mixture prepared in (i) into a continuous flow reactor at a liquid hourly space velocity in the range of from 0.3 to 20 h.sup.−1 for a duration of at least 1 h; and (iii) crystallizing the zeolitic material from the mixture in the continuous flow reactor, wherein the mixture is heated to a temperature in the range of from 100 to 300° C.; wherein the volume of the continuous flow reactor is in the range of from 150 cm.sup.3 to 75 m.sup.3, as well as to zeolitic materials which may be obtained according to the inventive process and to their use.

The present disclosure relates to a molecular sieve, preparation thereof and acoustic absorption material and speaker containing the same. The molecular sieve having an MFI-structure, comprising a framework and an off-framework cation, wherein the framework comprises SiO.sub.2 and a metal oxide M.sub.xO.sub.y with M comprising boron, gallium or aluminium; the off-framework cation is at least one of hydrogen ion, alkali metal ion and alkaline earth metal ion. The molecular herein can effectively prevent the failure of the molecular sieve and improve the performance stability of the speaker.

The present disclosure relates to a molecular sieve, preparation thereof and acoustic absorption material and speaker containing the same. The molecular sieve having an MFI-structure, comprising a framework and an off-framework cation, wherein the framework comprises SiO.sub.2 and a metal oxide M.sub.xO.sub.y with M comprising boron, gallium or aluminium; the off-framework cation is at least one of hydrogen ion, alkali metal ion and alkaline earth metal ion. The molecular herein can effectively prevent the failure of the molecular sieve and improve the performance stability of the speaker.

A process comprising hydrothermally synthesizing a titanium-containing zeolitic material having framework type MWW in the presence of an MWW template compound, obtaining a mother liquor comprising water, a first portion of the MWW template compound and a titanium-containing zeolitic material having framework type MWW comprising a second portion of the MWW template compound, separating the first portion of the MWW template compound from the mother liquor and recycling the first portion of the MWW template compound into a hydrothermal synthesis of a titanium-containing zeolitic material having framework type MWW.